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From Wikipedia, the free encyclopedia

Ooids (from Ancient Greek ᾠόν (ōión) 'egg stone') are small (commonly ≤2 mm in diameter), spheroidal, "coated" (layered) sedimentary grains, usually composed of calcium carbonate, but sometimes made up of iron- or phosphate-based minerals. Ooids usually form on the sea floor, most commonly in shallow tropical seas (around the Bahamas, for example, or in the Persian Gulf). After being buried under additional sediment, these ooid grains can be cemented together to form a sedimentary rock called an . Oolites usually consist of calcium carbonate; these belong to the limestone rock family. Pisoids are similar to ooids, but are larger than 2 mm in diameter, often considerably larger, as with the pisoids in the hot springs at Carlsbad ( Karlovy Vary) in the Czech Republic.

An ooid forms as a series of concentric layers around a nucleus. The layers contain crystals arranged radially, tangentially or randomly. The nucleus can be a shell fragment, quartz grain or any other small fragment. Most modern ooids are aragonite, a polymorph of calcium carbonate; some are composed of high-magnesium calcite, and some are bimineralic (layers of calcite and aragonite). Ancient ooids can be calcitic, either originally precipitated as calcite (as in calcite seas), or formed by alteration (neomorphic replacement) of aragonitic ooids (or the aragonite layers in originally bimineralic ooids). Moldic ooids (or molds later filled in by calcite cement) occur in both young and ancient rocks, indicating the removal of a soluble polymorph (usually aragonite).

Whether ooids become calcitic or aragonitic can be linked to strontium/ calcium substitution within the crystalline structure. This has been shown in some examples to be due to temperature fluctuations in marine environments, which affects salinity levels, which in turn facilitate the substitution. Marine calcitic ooids were typically formed during calcite sea intervals, especially during the Ordovician and the Jurassic Periods. The geochemistry of these seas was a function of seafloor spreading and fluctuating Mg/Ca ratios. Low Mg/Ca ratios favor the precipitation of low-magnesium calcite.

Ooids with radial crystals (such as the aragonitic ooids in the Great Salt Lake, Utah, US) grow by ions extending the lattices of the radial crystals. The mode of growth of ooids with tangential (usually minute needle-like) crystals is less clear. They may be accumulated in a "snowball" fashion from tiny crystals in the sediment or water, or they may crystallize in place on the ooid surface. A hypothesis of growth by accretion (like a snowball) from the polymineralic sediment of fine aragonite, high-magnesium calcite (HMC) and low-magnesium calcite (LMC), must explain how only aragonite needles are added to the ooid cortex. Both in tangential and in radial ooids, the cortex is composed of many very fine increments of growth. Some modern (and ancient) ooids partially or totally lack clear layering and have a micritic (very fine grained) texture. Examination of such micritic ooids by scanning electron microscopy often shows evidence of microbial borings later filled by fine cement.

There are several factors that affect ooid growth: supersaturation of the water with respect to calcium carbonate, the availability of nuclei, agitation of the ooids, water depth, and the role of microbes.

Sometimes fossils are included in ooids, often forming the nuclei. This taphonomic process is termed ooimmuration (Wilson et al., 2021). The formation of the ooid cortex around the test or shell protects it from abrasion, fragmentation and bioerosion. Ooimmuration also retains fine organic remains that would ordinarily be winnowed away by currents.

Flügel, Erik (2010), Microfacies of Carbonate Rocks: Analysis, Interpretation and Application, 2nd ed., Springer, pp. 242-244. ISBN 978-3-642-03795-5. Accessed 2014-06-23.

Wilson, M.A., Cooke, A.M., Judge, S.A. and Palmer, T.J. 2021. Ooimmuration: Enhanced fossil preservation by ooids, with examples from the Middle Jurassic of southwestern Utah, USA. Palaios 36: 326-329. https://doi.org/10.2110/palo.2021.036

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From Wikipedia, the free encyclopedia Ooids (from Ancient Greek ᾠόν (ōión) 'egg stone') are small (commonly ≤2 mm in diameter), spheroidal, "coated" (layered) sedimentary grains, usually composed of calcium carbonate, but sometimes made up of iron- or phosphate-based minerals.

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A pearl is a hard glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as a conulariid. Just like the shell of a mollusk, a pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) in minute crystalline form, which has been deposited in concentric layers.

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chemical formula CaCO3 for Calcium carbonate

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chemical formula CaCO3 for Calcium carbonate

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https://en.wikipedia.org/wiki/Calcium_carbonate

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Names

IUPAC name

Other names

Identifiers

DrugBank

ECHA InfoCard

100.006.765

EC Number

E number

E170 (colours)

RTECS number

InChI=1S/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2

Key: VTYYLEPIZMXCLO-UHFFFAOYSA-L

InChI=1/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2

Key: VTYYLEPIZMXCLO-NUQVWONBAS

Properties

CaCO ₃

Molar mass

100.0869 g/mol

Appearance

Fine white powder; chalky taste

Odor

odorless

Density

2.711 g/cm ³ ( calcite)
2.83 g/cm ³ ( aragonite)

Melting point

1,339 °C (2,442 °F; 1,612 K) (calcite)
825 °C (1,517 °F; 1,098 K) (aragonite)[4][5]

Boiling point

decomposes

0.013 g/L (25 °C)[1][2]

[3]

Solubility in dilute acids

soluble

Acidity (p K a)

9.0

−3.82×10 −5 cm ³/mol

1.59

Structure

Trigonal

32/m

Thermochemistry

93 J·mol −1·K −1[6]

−1207 kJ·mol −1[6]

Pharmacology

A02AC01 ( WHO) A12AA04 ( WHO)

Hazards

NFPA 704 (fire diamond)

Lethal dose or concentration (LD, LC):

6450 mg/kg (oral, rat)

NIOSH (US health exposure limits):

TWA 15 mg/m ³ (total) TWA 5 mg/m ³ (resp)[7]

Safety data sheet (SDS)

ICSC 1193

Related compounds

Calcium bicarbonate

Beryllium carbonate
Magnesium carbonate
Strontium carbonate
Barium carbonate
Radium carbonate

Calcium sulfate

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Calcium carbonate is a chemical compound with the chemical formula . It is a common substance found in rocks as the minerals calcite and aragonite (most notably as limestone, which is a type of sedimentary rock consisting mainly of calcite) and is the main component of eggshells, gastropod shells, shellfish skeletons and pearls. Things containing much calcium carbonate or resembling it are described as calcareous. Calcium carbonate is the active ingredient in agricultural lime and is created when calcium ions in hard water react with carbonate ions to create limescale. It has medical use as a calcium supplement or as an antacid, but excessive consumption can be hazardous and cause hypercalcemia and digestive issues.

Calcium carbonate shares the typical properties of other carbonates. Notably it

Calcium carbonate reacts with water that is saturated with carbon dioxide to form the soluble calcium bicarbonate.

This reaction is important in the erosion of carbonate rock, forming caverns, and leads to hard water in many regions.

An unusual form of calcium carbonate is the hexahydrate ikaite, . Ikaite is stable only below 8 °C.

The vast majority of calcium carbonate used in industry is extracted by mining or quarrying. Pure calcium carbonate (such as for food or pharmaceutical use), can be produced from a pure quarried source (usually marble).

Alternatively, calcium carbonate is prepared from calcium oxide. Water is added to give calcium hydroxide then carbon dioxide is passed through this solution to precipitate the desired calcium carbonate, referred to in the industry as precipitated calcium carbonate (PCC) This process is called carbonatation:

In a laboratory, calcium carbonate can easily be crystallized from calcium chloride (CaCl ₂), by placing an aqueous solution of CaCl ₂ in a desiccator alongside ammonium carbonate (NH4) ₂CO ₃. In the desiccator, ammonium carbonate is exposed to air and decomposes into ammonia, carbon dioxide, and water. The carbon dioxide then diffuses into the aqueous solution of calcium chloride, reacts with the calcium ions and the water, and forms calcium carbonate.

The thermodynamically stable form of under normal conditions is hexagonal β- (the mineral calcite). Other forms can be prepared, the denser (2.83 g/cm ³) orthorhombic λ- (the mineral aragonite) and hexagonal μ-, occurring as the mineral vaterite. The aragonite form can be prepared by precipitation at temperatures above 85 °C; the vaterite form can be prepared by precipitation at 60 °C. Calcite contains calcium atoms coordinated by six oxygen atoms; in aragonite they are coordinated by nine oxygen atoms. The vaterite structure is not fully understood. Magnesium carbonate () has the calcite structure, whereas strontium carbonate () and barium carbonate () adopt the aragonite structure, reflecting their larger ionic radii.

Calcium carbonate crystallizes in three anhydrous polymorphs, of which calcite is the thermodynamically most stable at room temperature, aragonite is only slightly less so, and vaterite is the least stable.

The calcite crystal structure is trigonal, with space group (No. 167 in the International Tables for Crystallography[16]), and Pearson symbol .[17] Aragonite is orthorhombic, with space group (No 62), and Pearson Symbol .[18] Vaterite is composed of at least two different coexisting crystallographic structures. The major structure exhibits hexagonal symmetry in space group , the minor structure is still unknown.[19]

All three polymorphs crystallize simultaneously from aqueous solutions under ambient conditions. In additive-free aqueous solutions, calcite forms easily as the major product, while aragonite appears only as a minor product.

At high saturation, vaterite is typically the first phase precipitated, which is followed by a transformation of the vaterite to calcite. This behavior seems to follow Ostwald's rule, in which the least stable polymorph crystallizes first, followed by the crystallization of different polymorphs via a sequence of increasingly stable phases. However, aragonite, whose stability lies between those of vaterite and calcite, seems to be the exception to this rule, as aragonite does not form as a precursor to calcite under ambient conditions.

Aragonite occurs in majority when the reaction conditions inhibit the formation of calcite and/or promote the nucleation of aragonite. For example, the formation of aragonite is promoted by the presence of magnesium ions, or by using proteins and peptides derived from biological calcium carbonate. Some polyamines such as cadaverine and Poly(ethylene imine) have been shown to facilitate the formation of aragonite over calcite.

Organisms, such as molluscs and arthropods, have shown the ability to grow all three crystal polymorphs of calcium carbonate, mainly as protection (shells) and muscle attachments. Moreover, they exhibit a remarkable capability of phase selection over calcite and aragonite, and some organisms can switch between the two polymorphs. The ability of phase selection is usually attributed to the use of specific macromolecules or combinations of macromolecules by such organisms.

Calcite, aragonite and vaterite are pure calcium carbonate minerals. Industrially important source rocks which are predominantly calcium carbonate include limestone, chalk, marble and travertine.

Eggshells, snail shells and most seashells are predominantly calcium carbonate and can be used as industrial sources of that chemical. Oyster shells have enjoyed recent recognition as a source of dietary calcium, but are also a practical industrial source. Dark green vegetables such as broccoli and kale contain dietarily significant amounts of calcium carbonate, but they are not practical as an industrial source.

Beyond Earth, strong evidence suggests the presence of calcium carbonate on Mars. Signs of calcium carbonate have been detected at more than one location (notably at Gusev and Huygens craters). This provides some evidence for the past presence of liquid water.

Carbonate is found frequently in geologic settings and constitutes an enormous carbon reservoir. Calcium carbonate occurs as aragonite, calcite and dolomite as significant constituents of the calcium cycle. The carbonate minerals form the rock types: limestone, chalk, marble, travertine, tufa, and others.

In warm, clear tropical waters corals are more abundant than towards the poles where the waters are cold. Calcium carbonate contributors, including plankton (such as coccoliths and planktic foraminifera), coralline algae, sponges, brachiopods, echinoderms, bryozoa and mollusks, are typically found in shallow water environments where sunlight and filterable food are more abundant. Cold-water carbonates do exist at higher latitudes but have a very slow growth rate. The calcification processes are changed by ocean acidification.

Where the oceanic crust is subducted under a continental plate sediments will be carried down to warmer zones in the asthenosphere and lithosphere. Under these conditions calcium carbonate decomposes to produce carbon dioxide which, along with other gases, give rise to explosive volcanic eruptions.

The carbonate compensation depth (CCD) is the point in the ocean where the rate of precipitation of calcium carbonate is balanced by the rate of dissolution due to the conditions present. Deep in the ocean, the temperature drops and pressure increases. Calcium carbonate is unusual in that its solubility increases with decreasing temperature. Increasing pressure also increases the solubility of calcium carbonate. The carbonate compensation depth can range from 4,000 to 6,000 meters below sea level.

Calcium carbonate can preserve fossils through permineralization. Most of the vertebrate fossils of the Two Medicine Formation-a geologic formation known for its duck-billed dinosaur eggs-are preserved by permineralization. This type of preservation conserves high levels of detail, even down to the microscopic level. However, it also leaves specimens vulnerable to weathering when exposed to the surface.

Trilobite populations were once thought to have composed the majority of aquatic life during the Cambrian, due to the fact that their calcium carbonate-rich shells were more easily preserved than those of other species, which had purely chitinous shells.

The main use of calcium carbonate is in the construction industry, either as a building material, or limestone aggregate for road building, as an ingredient of cement, or as the starting material for the preparation of builders' lime by burning in a kiln. However, because of weathering mainly caused by acid rain, calcium carbonate (in limestone form) is no longer used for building purposes on its own, but only as a raw primary substance for building materials.

Calcium carbonate is also used in the purification of iron from iron ore in a blast furnace. The carbonate is calcined in situ to give calcium oxide, which forms a slag with various impurities present, and separates from the purified iron.

In the oil industry, calcium carbonate is added to drilling fluids as a formation-bridging and filtercake-sealing agent; it is also a weighting material which increases the density of drilling fluids to control the downhole pressure. Calcium carbonate is added to swimming pools, as a pH corrector for maintaining alkalinity and offsetting the acidic properties of the disinfectant agent.

It is also used as a raw material in the refining of sugar from sugar beet; it is calcined in a kiln with anthracite to produce calcium oxide and carbon dioxide. This burnt lime is then slaked in fresh water to produce a calcium hydroxide suspension for the precipitation of impurities in raw juice during carbonatation.

Calcium carbonate in the form of chalk has traditionally been a major component of blackboard chalk. However, modern manufactured chalk is mostly gypsum, hydrated calcium sulfate . Calcium carbonate is a main source for growing biorock. Precipitated calcium carbonate (PCC), pre-dispersed in slurry form, is a common filler material for latex gloves with the aim of achieving maximum saving in material and production costs.

Fine ground calcium carbonate (GCC) is an essential ingredient in the microporous film used in diapers and some building films, as the pores are nucleated around the calcium carbonate particles during the manufacture of the film by biaxial stretching. GCC and PCC are used as a filler in paper because they are cheaper than wood fiber. In terms of market volume, GCC are the most important types of fillers currently used. Printing and writing paper can contain 10-20% calcium carbonate. In North America, calcium carbonate has begun to replace kaolin in the production of glossy paper. Europe has been practicing this as alkaline papermaking or acid-free papermaking for some decades. PCC used for paper filling and paper coatings is precipitated and prepared in a variety of shapes and sizes having characteristic narrow particle size distributions and equivalent spherical diameters of 0.4 to 3 micrometers.[citation needed ]

Calcium carbonate is widely used as an extender in paints, in particular matte emulsion paint where typically 30% by weight of the paint is either chalk or marble. It is also a popular filler in plastics. Some typical examples include around 15 to 20% loading of chalk in unplasticized polyvinyl chloride (uPVC) drainpipes, 5% to 15% loading of stearate-coated chalk or marble in uPVC window profile. PVC cables can use calcium carbonate at loadings of up to 70 phr (parts per hundred parts of resin) to improve mechanical properties (tensile strength and elongation) and electrical properties (volume resistivity).[citation needed ] Polypropylene compounds are often filled with calcium carbonate to increase rigidity, a requirement that becomes important at high usage temperatures. Here the percentage is often 20-40%. It also routinely used as a filler in thermosetting resins (sheet and bulk molding compounds) and has also been mixed with ABS, and other ingredients, to form some types of compression molded "clay" poker chips. Precipitated calcium carbonate, made by dropping calcium oxide into water, is used by itself or with additives as a white paint, known as whitewashing.

Calcium carbonate is added to a wide range of trade and do it yourself adhesives, sealants, and decorating fillers. Ceramic tile adhesives typically contain 70% to 80% limestone. Decorating crack fillers contain similar levels of marble or dolomite. It is also mixed with putty in setting stained glass windows, and as a resist to prevent glass from sticking to kiln shelves when firing glazes and paints at high temperature.

In ceramic glaze applications, calcium carbonate is known as whiting, and is a common ingredient for many glazes in its white powdered form. When a glaze containing this material is fired in a kiln, the whiting acts as a flux material in the glaze. Ground calcium carbonate is an abrasive (both as scouring powder and as an ingredient of household scouring creams), in particular in its calcite form, which has the relatively low hardness level of 3 on the Mohs scale, and will therefore not scratch glass and most other ceramics, enamel, bronze, iron, and steel, and have a moderate effect on softer metals like aluminium and copper. A paste made from calcium carbonate and deionized water can be used to clean tarnish on silver.

Calcium carbonate is widely used medicinally as an inexpensive dietary calcium supplement for gastric antacid (such as Tums and Eno). It may be used as a phosphate binder for the treatment of hyperphosphatemia (primarily in patients with chronic kidney failure). It is used in the pharmaceutical industry as an inert filler for tablets and other pharmaceuticals.

Calcium carbonate is used in the production of calcium oxide as well as toothpaste and has seen a resurgence as a food preservative and color retainer, when used in or with products such as organic apples.

Calcium carbonate is used therapeutically as phosphate binder in patients on maintenance haemodialysis. It is the most common form of phosphate binder prescribed, particularly in non-dialysis chronic kidney disease. Calcium carbonate is the most commonly used phosphate binder, but clinicians are increasingly prescribing the more expensive, non-calcium-based phosphate binders, particularly sevelamer.

Excess calcium from supplements, fortified food, and high-calcium diets can cause milk-alkali syndrome, which has serious toxicity and can be fatal. In 1915, Bertram Sippy introduced the "Sippy regimen" of hourly ingestion of milk and cream, and the gradual addition of eggs and cooked cereal, for 10 days, combined with alkaline powders, which provided symptomatic relief for peptic ulcer disease. Over the next several decades, the Sippy regimen resulted in kidney failure, alkalosis, and hypercalcaemia, mostly in men with peptic ulcer disease. These adverse effects were reversed when the regimen stopped, but it was fatal in some patients with protracted vomiting. Milk-alkali syndrome declined in men after effective treatments for peptic ulcer disease arose. Since the 1990s it has been most frequently reported in women taking calcium supplements above the recommended range of 1.2 to 1.5 grams daily, for prevention and treatment of osteoporosis, and is exacerbated by dehydration. Calcium has been added to over-the-counter products, which contributes to inadvertent excessive intake. Excessive calcium intake can lead to hypercalcemia, complications of which include vomiting, abdominal pain and altered mental status.

As a food additive it is designated E170, and it has an INS number of 170. Used as an acidity regulator, anticaking agent, stabilizer or color it is approved for usage in the EU, US and Australia and New Zealand. It is "added by law to all UK milled bread flour except wholemeal". It is used in some soy milk and almond milk products as a source of dietary calcium; at least one study suggests that calcium carbonate might be as bioavailable as the calcium in cow's milk. Calcium carbonate is also used as a firming agent in many canned and bottled vegetable products.

Several calcium supplement formulations have been documented to contain the chemical element lead, posing a public health concern. Lead is commonly found in natural sources of calcium.

Agricultural lime, powdered chalk or limestone, is used as a cheap method for neutralising acidic soil, making it suitable for planting, also used in aquaculture industry for pH regulation of pond soil before initiating culture.

Calcium carbonate is a key ingredient in many household cleaning powders like Comet and is used as a scrubbing agent.

In 1989, a researcher, Ken Simmons, introduced into the Whetstone Brook in Massachusetts. His hope was that the calcium carbonate would counter the acid in the stream from acid rain and save the trout that had ceased to spawn. Although his experiment was a success, it did increase the amount of aluminium ions in the area of the brook that was not treated with the limestone. This shows that can be added to neutralize the effects of acid rain in river ecosystems. Currently calcium carbonate is used to neutralize acidic conditions in both soil and water. Since the 1970s, such liming has been practiced on a large scale in Sweden to mitigate acidification and several thousand lakes and streams are limed repeatedly.

Calcium carbonate is also used in flue gas desulfurisation applications eliminating harmful and emissions from coal and other fossil fuels burnt in large fossil fuel power stations.

Calcination of limestone using charcoal fires to produce quicklime has been practiced since antiquity by cultures all over the world. The temperature at which limestone yields calcium oxide is usually given as 825 °C, but stating an absolute threshold is misleading. Calcium carbonate exists in equilibrium with calcium oxide and carbon dioxide at any temperature. At each temperature there is a partial pressure of carbon dioxide that is in equilibrium with calcium carbonate. At room temperature the equilibrium overwhelmingly favors calcium carbonate, because the equilibrium pressure is only a tiny fraction of the partial pressure in air, which is about 0.035 kPa.

At temperatures above 550 °C the equilibrium pressure begins to exceed the pressure in air. So above 550 °C, calcium carbonate begins to outgas into air. However, in a charcoal fired kiln, the concentration of will be much higher than it is in air. Indeed, if all the oxygen in the kiln is consumed in the fire, then the partial pressure of in the kiln can be as high as 20 kPa.

The table shows that this partial pressure is not achieved until the temperature is nearly 800 °C. For the outgassing of from calcium carbonate to happen at an economically useful rate, the equilibrium pressure must significantly exceed the ambient pressure of . And for it to happen rapidly, the equilibrium pressure must exceed total atmospheric pressure of 101 kPa, which happens at 898 °C.

Calcium carbonate is poorly soluble in pure water (47 mg/L at normal atmospheric partial pressure as shown below).

The equilibrium of its solution is given by the equation (with dissolved calcium carbonate on the right):

where the solubility product for is given as anywhere from K sp = to K sp = at 25 °C, depending upon the data source. What the equation means is that the product of molar concentration of calcium ions ( moles of dissolved per liter of solution) with the molar concentration of dissolved cannot exceed the value of K sp. This seemingly simple solubility equation, however, must be taken along with the more complicated equilibrium of carbon dioxide with water (see carbonic acid). Some of the combines with in the solution according to

is known as the bicarbonate ion. Calcium bicarbonate is many times more soluble in water than calcium carbonate-indeed it exists only in solution.

Some of the combines with in solution according to

Some of the breaks up into water and dissolved carbon dioxide according to

And dissolved carbon dioxide is in equilibrium with atmospheric carbon dioxide according to

For ambient air, P is around atmospheres (or equivalently 35 Pa). The last equation above fixes the concentration of dissolved as a function of P, independent of the concentration of dissolved . At atmospheric partial pressure of , dissolved concentration is moles per liter. The equation before that fixes the concentration of as a function of concentration. For [] = , it results in = moles per liter. When is known, the remaining three equations together with

(which is true for all aqueous solutions), and the fact that the solution must be electrically neutral, i.e., the overall charge of dissolved positive ions must be cancelled out by the overall charge of dissolved negative ions , make it possible to solve simultaneously for the remaining five unknown concentrations (note that the previously mentioned form of the neutrality is valid only if calcium carbonate has been put in contact with pure water or with a neutral pH solution; in the case where the initial water solvent pH is not neutral, the balance is not neutral).

The adjacent table shows the result for and (in the form of pH) as a function of ambient partial pressure of ( K sp = has been taken for the calculation).

At atmospheric levels of ambient the table indicates that the solution will be slightly alkaline with a maximum solubility of 47 mg/L.

As ambient partial pressure is reduced below atmospheric levels, the solution becomes more and more alkaline. At extremely low P, dissolved , bicarbonate ion, and carbonate ion largely evaporate from the solution, leaving a highly alkaline solution of calcium hydroxide, which is more soluble than . Note that for P = 10−12 atm, the product is still below the solubility product of (). For still lower pressure, precipitation will occur before precipitation.

As ambient partial pressure increases to levels above atmospheric, pH drops, and much of the carbonate ion is converted to bicarbonate ion, which results in higher solubility of .

The effect of the latter is especially evident in day-to-day life of people who have hard water. Water in aquifers underground can be exposed to levels of much higher than atmospheric. As such water percolates through calcium carbonate rock, the dissolves according to the second trend. When that same water then emerges from the tap, in time it comes into equilibrium with levels in the air by outgassing its excess . The calcium carbonate becomes less soluble as a result, and the excess precipitates as lime scale. This same process is responsible for the formation of stalactites and stalagmites in limestone caves.

Two hydrated phases of calcium carbonate, monohydrocalcite and ikaite , may precipitate from water at ambient conditions and persist as metastable phases.

With varying pH, temperature and salinity: scaling in swimming pools

In contrast to the open equilibrium scenario above, many swimming pools are managed by addition of sodium bicarbonate () to about 2 mM as a buffer, then control of pH through use of HCl, , , NaOH or chlorine formulations that are acidic or basic. In this situation, dissolved inorganic carbon ( total inorganic carbon) is far from equilibrium with atmospheric . Progress towards equilibrium through outgassing of is slowed by

1. limited aeration in a deep water column; and

2. periodic replenishment of bicarbonate to maintain buffer capacity (often estimated through measurement of total alkalinity).

In this situation, the dissociation constants for the much faster reactions

allow the prediction of concentrations of each dissolved inorganic carbon species in solution, from the added concentration of (which constitutes more than 90% of Bjerrum plot species from pH 7 to pH 8 at 25 °C in fresh water). Addition of will increase concentration at any pH. Rearranging the equations given above, we can see that = , and [] = . Therefore, when concentration is known, the maximum concentration of ions before scaling through precipitation can be predicted from the formula:

The solubility product for ( K sp) and the dissociation constants for the dissolved inorganic carbon species (including K a2) are all substantially affected by temperature and salinity, with the overall effect that [] max increases from freshwater to saltwater, and decreases with rising temperature, pH, or added bicarbonate level, as illustrated in the accompanying graphs.

The trends are illustrative for pool management, but whether scaling occurs also depends on other factors including interactions with , and other ions in the pool, as well as supersaturation effects. Scaling is commonly observed in electrolytic chlorine generators, where there is a high pH near the cathode surface and scale deposition further increases temperature. This is one reason that some pool operators prefer borate over bicarbonate as the primary pH buffer, and avoid the use of pool chemicals containing calcium.

Solutions of strong ( HCl), moderately strong ( sulfamic) or weak ( acetic, citric, sorbic, lactic, phosphoric) acids are commercially available. They are commonly used as descaling agents to remove limescale deposits. The maximum amount of that can be "dissolved" by one liter of an acid solution can be calculated using the above equilibrium equations.

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Names IUPAC name Other names Identifiers DrugBank ECHA InfoCard 100.006.765 EC Number E number E170 (colours) RTECS number InChI=1S/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2 Key: VTYYLEPIZMXCLO-UHFFFAOYSA-L InChI=1/CH2O3.Ca/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2 Key: VTYYLEPIZMXCLO-NUQVWONBAS Properties CaCO 3 Molar mass 100.0869 g/mol Appearance Fine white powder; chalky taste Odor odorless Density 2.711 g/cm 3 ( calcite)2.83 g/cm 3 ( aragonite) Melting

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As the chemistry of chocolate is a topic that's been pretty much exhausted on the site (see here, here, here, here, and here), for the Easter weekend we're instead homing in on the 'egg' side of Easter Eggs. For such a simple staple of the kitchen, the chemistry of eggs is surprisingly complex. Here we take a brief look at their composition, and also at some chemistry tips that can help with cooking them!
The Egg's Shell
It makes sense to start from the outside of the egg and work our way in, so let's begin with the egg's shell. It's made primarily from calcium carbonate, the chemical compound which also makes up the majority of sea shells, as well as chalk and limestone. Nanoparticles of calcium carbonate are arranged into ordered crystals by proteins, eventually forming the calcite mineral that makes up the shell. The shell isn't actually completely solid - it has thousands of tiny pores, around 9,000 on average, which allow gases to pass in and out. As we'll see later, this can have implications for cooking.

The colour of egg shells can also vary; chicken eggs tend to be somewhere on a colour spectrum between white and brown, but the eggs of other avian species can also encompass blue or green hues. This colouration is due to the deposition of pigment molecules on the eggshell whilst it is being formed in the chicken's oviduct. One pigment, protoporphyrin IX, gives shells a brown colour. This pigment is a precursor of haemoglobin, the oxygen-carrying compound found in blood. Other pigments, such as oocyanin which gives blue and green colours, are side-products from the formation of bile. White egg shells have an absence of pigment molecules.
The Egg White
Once inside the egg, we first come to the egg white, or albumen. The egg white is formed of a number of different layers, and is in fact mostly composed of water (90%). A range of proteins make up the majority of the remaining 10%, serving a number of varying purposes. Some, such as ovalbumin, are thought to provide nourishment for the developing chick, whilst also blocking the action of digestive enzymes. Another, conalbumin or ovatransferrin, binds iron atoms tightly, both to prevent their use by bacteria and hence help prevent infection, but also to ensure a supply of iron for the developing chick. Finally, one of the most important proteins in the albumen in terms of the egg white's consistency is ovomucin. This protein helps to thicken the egg white and give it its gloopy consistency.
The Egg Yolk
The egg's yolk is made up of a number of spherical compartments. Unlike the egg white, which contains very little fat, the yolk contains a significant amount of fatty acids such as oleic acid, palmitic acid, and linoleic acid, as well as high level of cholesterol. It also contains fat soluble vitamins (A, D, E, and K).

The colour of the yolk is a consequence of the presence of two chemical compounds: lutein and zeaxanthin. These are both compounds known as xanthophylls, and can also be classed as carotenoid compounds; they are hence members of the same chemical family to which beta-carotene, the chemical that gives carrots their orange colour, belongs. A chicken's feed can influence the colour of the yolk, and for this reason beta-carotene-containing substances, or even marigold petals, can be added to chicken feed to enhance the colour. Interestingly, including the main colour-creating compounds in red peppers, capsanthin and capsorubin, in chicken feed can cause the yolks to appear a deep orange or even red.
Cooking Eggs
So, now we know a little about what eggs are made of, what's actually going on when we cook one? This is largely a consequence of what happens to the proteins in the egg when we heat them. To begin with, in a raw egg the long protein molecules are individually coiled up. However, as we heat them, these chains begin to unfold, a process known as 'denaturing'. Once unravelled, the proteins form a three-dimensional network, trapping water into tiny pockets in the network, and causing solidification. The egg white changes from being transparent to opaque due to the clustered protein network deflecting light instead of allowing it to pass through.

In terms of the compounds that give eggs their flavour, remarkably few studies have been carried out to gauge which compounds make important contributions. However, we do know that hydrogen sulfide is the most important contributor to the characteristic eggy smell. This compound is created as sulfur-containing proteins in the egg white react during cooking. The longer an egg is cooked, the greater the amount of hydrogen sulfide that is produced, and older eggs also produce it in higher amounts when cooked. Spoiled eggs smell unpleasant because of even higher levels of hydrogen sulfide.

Hydrogen sulfide can also play a part in the appearance of a green layer around the egg yolk that can sometimes occur. This is due to the reaction of the gas with iron in the egg yolk to create iron sulfide, which forms the green layer. Often prolonged heating of the egg during cooking can cause this; though it is harmless, it can be prevented by cooling the eggs quickly after cooking by immersing them in cold water.

When hard-boiling eggs, how old the egg is can influence how difficult the egg shell is to peel off. This is due to the change in alkalinity of the egg white over time. As the egg shell contains thousands of pores that allow carbon dioxide gas to diffuse out of the egg, the egg white's pH rises from around 7.6 to around 9.2 after around a week of storage. The cooked albumen adheres more strongly to the inside of the shell at the lower pH, meaning fresh eggs make for a more frustrating egg-peeling experience. By contrast, it's much easier with an older egg.

To combat this, if you're making boiled eggs using fresh eggs, it's suggested that baking soda can be added to the water in which the eggs are being cooked to make it more alkaline - though this can also make the eggs taste a little more sulfury, and whether it actually makes any real difference is disputed. Adding salt to the water can help if the egg springs a crack during cooking, as egg white solidifies more quickly in salted water, though again there's not really any evidence that it makes the eggs easier to peel.
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References & Further Reading

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As the chemistry of chocolate is a topic that's been pretty much exhausted on the site (see here, here, here, here, and here), for the Easter weekend we're instead homing in on the 'egg' side of Easter Eggs. For such a simple staple of the kitchen, the chemistry of eggs is surprisingly complex.

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Lapis definition, stone (used in Latin names for minerals, gems, etc.) See more.

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Diamant Rocket (Diamant is French for diamond)

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Diamant Rocket (Diamant is French for diamond)

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Country of origin

France

Height

A: 18.95 m (62.2 ft)

B: 23.5 m (77 ft)

BP4: 21.6 m (71 ft)

Diameter

1.34 m (4 ft 5 in)

Mass

18,400 kg (40,600 lb)

Stages

3

Mass

160 kg (350 lb)

Status

Retired

Launch sites

A: Hammaguir
B/BP4: Kourou

Total launches

12 (A :4, B: 5, BP4: 3)

Success(es)

9 (A: 3, B: 3, BP4: 3)

Failure(s)

3 (A: 1, B: 2)

First flight

A: 26 November 1965
B:10 March 1970
BP4:6 February 1975

Last flight

A: 15 February 1967
B:21 May 1973
BP4: 27 September 1975

Burn time

93 seconds

Propellant

Nitric Acid/ Turpentine

Powered by

1 [ Valois fr]

Burn time

110 seconds

Propellant

N2O4/ UDMH

Burn time

39 seconds

Powered by

1 P-4

Burn time

55 seconds

Powered by

1 P-064

Burn time

39 seconds

Powered by

1 P-068

Burn time

46 seconds

The Diamant rocket (French for " diamond") was the first exclusively French expendable launch system and at the same time the first satellite launcher not built by either the United States or USSR. As such, it has been referred to as being a key predecessor for all subsequent European launcher projects.

During 1962, development of the Diamant commenced as the inaugural spacecraft project of France's space agency, the Centre National d'Études Spatiales (CNES). As a project, it was derived from the military program Pierres précieuses (fr.: gemstones) that included the five prototypes Agate, Topaze, Emeraude, Rubis and Saphir ( Agate, Topaz, Emerald, Ruby and Sapphire), and drew heavily upon the knowledge and technologies that had been previously developed. On 26 November 1965, the Diamant A performed its maiden flight. Out of a total of 12 launch attempts to be performed between 1965 and 1975, 9 of these were successful. Most notably, on 26 November 1965, the Diamant was used to successfully launch the first French satellite, named Astérix.

Three successive versions of the Diamant rocket were developed, designated A, B and BP4. All versions had three stages and a payload of approximately 150 kg for a 200 km orbit. Despite the success of the Diamant as a launcher, France ultimately chose to terminate further work on its national launcher program in favor of participation in the multi-European programme to produce what would become the Ariane launcher in 1975.

During the late 1940s and 1950s, substantial interest arose amongst the international powers of the era in the development of rocketry and missile technology, in particular the prospects for ballistic missiles capable of travelling great distances. Both of the emergent superpowers of the time, the United States and the Union of Soviet Socialist Republics (USSR) chose to invest heavily within this new field, observing its political and military importance; it was not long before a highly competitive atmosphere emerged where neither entity wished to fall behind the other in missile technology, which directly led to the so-called ' space race'. In addition, other nations also sought to make headway with this technology, often seeking to exploit and build upon knowledge which had been acquired from Nazi Germany's V2 programme. In western Europe, both the United Kingdom and France began making significant early steps in this field.

While Britain forged ahead with programmes such as the Black Knight ballistic missile demonstrator and the military-orientated Blue Steel missile programme, France also made progress on its own efforts. During 1949, the French government established the Laboratoire de Recherches Balistiques et Aérodynamiques at Vernon, outside Paris, for the purpose of pursuing its own military-focused ballistic missiles programmes. The agency initially conducted relatively straightforward and cost-conscious programmes, such as the development of the V2-based Veronique liquid-fuelled rocket in cooperation with a number of German scientists, which first flew during 1954. During 1957, having been suitably encouraged by the progress made, the Comité d'Action Scientifique de Défense Nationale (CASDN) decided to finance further refinements of the Veronique rocket.

During 1958, French wartime military leader Charles de Gaulle became President of France, establishing the Fifth Republic. De Gaulle, who was openly keen to develop a capable and fully independent French nuclear deterrent, determined that French-built missiles could comprise a potent element of the French military's fledgling nuclear arsenal, known as the Force de frappe; further impetus in favour of missile development was generated by the Sputnik crisis, a fear that other powers were falling behind the Soviet Union's progress in missile development, which had been provoked by the USSR's success with Sputnik 1, the first man-made satellite to be successfully orbited. A greatly expanded and renewed framework for missile-related development was promptly issued alongside generous government support for scientific research; specifically, the new efforts covered technologies such as intermediate-range ballistic missiles (IRBMs), submarine-launched ballistic missile, and reconnaissance satellites.

During 1959, the French government established the Comité de Recherches Spatiales (CRS), which would later be renamed as the Centre National d'Études Spatiales (CNES). The newly formed CRS, initially chaired by the French physicist Pierre Auger, was tasked with the coordination of all French research efforts in the field of space. From an early stage, the organisation's primary goal was to pursue the development of an indigenous expendable launch system with which payloads, such as satellites, could be launched into orbit. The indigenous launcher, which was promptly named Diamant, drew heavily from the military ballistic missile programmes which had preceded it; as such, much of the rocket's design was based upon these early missiles.

On 26 November 1965, the first Diamant rocket was fired from its launch site, the CIEES testing range, at Hammaguir, Bechar Province, Algeria. This maiden flight was deemed to be a success, achieving sufficient altitude and launching French's first satellite, a 42 kg test vehicle known as Astérix, into orbit; this feat has been viewed as cementing France as the third space power in the world, as well as affirming its independence and strategic capabilities. During 1966 and 1967, Diamant was used to launch three French-built scientific satellites. On 9 April 1968, the Guiana Space Centre, France's new national launching complex at Kourou, French Guiana, was officially declared to be operational; Diamant launches were subsequently shifted to this facility, along with various other missiles in use by France and, later on, other European nations as well.

On 10 March 1970, the first Diamant B rocket, an improved model of the launcher, was fired, carrying a pair of scientific satellite, named DIAL/MIKA and DIAL/WIKA, into orbit. Only one of the two satellites, which had been produced as a collaborative effort between France and Germany to study the Van Allen radiation belt around the Earth, survived the launch process. Overall, the Diamant rocket came to be recognised as a successful and reliable launch vehicle, competitive amongst even the best of its international competitors throughout the world during its time.

While Diamant had proven to be a viable and reliable launcher, the sheer size of the American and Soviet space programmes far exceeded what would be realistically achievable not only by France but by any of the independent nations of western Europe. As this realisation became prevalent, it was also recognised that cooperative efforts between nations and a new generation of international programmes would enable these nations to play a much greater and significant role in space exploration. Early collaborative programmes, such as the European Launcher Development Organisation (ELDO) and European Space Research Organisation (ESRO), bore mixed results but showed the promise of such endeavours, thus a greater emphasis was placed upon international efforts on the topic of space.

As a consequence of Britain's withdrawal from participation in the ELDO, it was decided to replace the British-built Blue Streak, which comprised the first stage of the organisation's multinational launcher, known as Europa, with the French-built Diamant taking its place. All work on the Europa programme was terminated only a few years later due to the high failure rate encountered. Meanwhile, Britain decided to focus its efforts on the indigenous Black Arrow launcher instead.

During 1974, the European Space Agency (ESA) was founded for this purpose; the ESA effectively enabled the competing and overlapping national space programmes to be succeeded by a single organised multinational framework with work shared between the member states instead. Specifically, in 1976, work commenced on the new collaborative Ariane 1 launcher, the first version of what would become the highly successful Ariane family. The existence of the Ariane programme, a rival launcher to the earlier Diamant rocket, effectively replaced the demand for and the role of France's indigenous launcher, rendering it obsolete and redundant in comparison. France ultimately decided to discontinue further launches using Diamant in favour of the newer Ariane platform.

This was the first version of the Diamant rockets, operational between 1965 and 1967. Remarkably for a newly developed system, all of the first four launches attempted launched were partly successful, the only failure occurring on the second launch when the payload was inserted into a lower orbit than planned. It possessed a first stage of 10 m, 1.4 metres in diameter, and a weight of 14.7 metric tons. Their engines of the type LRBA Vexin supplied a thrust of 269 kN for 93 seconds. The second stage was 4.7 metres long and had a diameter of 80 centimetres. It weighed 2.9 metric tons and developed a thrust of 165 kN for a duration of 44 seconds. The third stage is 2.65 m long and weighed 709 kilograms. It burned for 45 seconds and developed a thrust of 27 kN to 53 kN. Completely installed, a Diamant A was 18.95 metres high and weighed 18.4 metric tons.

An improved version of the Diamant A with a more powerful first stage. Five satellite launches were attempted between 1970 and 1973, of which the last two failed. All launches took place from Kourou in French Guiana.

Its first stage was 14.2 meters long, had a diameter of 1.4 metres and weighed 20.1 metric tons. Its engine developed a thrust of 316 kN to 400 kN (depending on flight altitude) for 116 seconds. The second stage was carried over from Diamant A without modification. The third stage was 1.67 metres long and had a diameter of 80 centimetres. It developed a thrust of 24 kN for 46 seconds. Completely assembled, a Diamant B was 23.5 metres high and weighed 24.6 metric tons.

This version incorporated a new second stage, while carrying the first and third stages over from its predecessor. It performed three successful launches in 1975, putting a total of four satellites into orbit. Its second stage, which was derived from the MSBS rocket, was 2.28 metres long and 1.5 metres in diameter and developed a thrust of 180 kN for 55 seconds.

Bleeker, J.A., Johannes Geiss and M. Huber. "The Century of Space Science." Springer Science & Business Media, 2012. ISBN 9-40100-320-3.

Turner, Martin J.L. "Rocket and Spacecraft Propulsion: Principles, Practice and New Developments." Springer Science & Business Media, 2008. ISBN 3-54069-203-7.

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Country of origin France Height A: 18.95 m (62.2 ft) B: 23.5 m (77 ft) BP4: 21.6 m (71 ft) Diameter 1.34 m (4 ft 5 in) Mass 18,400 kg (40,600 lb) Stages 3 Mass 160 kg (350 lb) Status Retired Launch sites A: Hammaguir B/BP4: Kourou Total launches 12

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The asterisk ( *), from Late Latin asteriscus, from Ancient Greek ἀστερίσκος , asteriskos, "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star.

Computer scientists and mathematicians often vocalize it as star (as, for example, in the A* search algorithm or ). In English, an asterisk is usually five- or six-pointed in sans-serif typefaces, six-pointed in serif typefaces, and six- or eight-pointed when handwritten. Its most common use is to call out a footnote. It is also often used to censor offensive words.

In computer science, the asterisk is commonly used as a wildcard character, or to denote pointers, repetition, or multiplication.

The asterisk has already been used as a symbol in ice age cave paintings. There is also a two-thousand-year-old character used by Aristarchus of Samothrace called the asteriskos, , which he used when proofreading Homeric poetry to mark lines that were duplicated. Origen is known to have also used the asteriskos to mark missing Hebrew lines from his Hexapla. The asterisk evolved in shape over time, but its meaning as a symbol used to correct defects remained.

In the Middle Ages, the asterisk was used to emphasize a particular part of text, often linking those parts of the text to a marginal comment. However, an asterisk was not always used.

One hypothesis to the origin of the asterisk is that it stems from the 5000-year-old Sumerian character dingir, 𒀭, though this hypothesis seems to only be based on visual appearance.

When toning down expletives, asterisks are often used to replace letters. For example, the word "badword" might become "ba***rd", "b*****d", "b******" or even "*******". Vowels tend to be censored with an asterisk more than consonants, but the intelligibility of censored profanities with multiple syllables such as "b*dw*rd" and "b*****d" or "ba****d", or uncommon ones is higher if put in context with surrounding text.

When a document containing classified information is published, the document may be "sanitized" ( redacted) by replacing the classified information with asterisks. For example, the Intelligence and Security Committee Russia report.

In colloquial usage, an asterisk attached to a sporting record indicates that it is somehow tainted. This is because results that have been considered dubious or set aside are recorded in the record books with an asterisk rendering to a footnote explaining the reason or reasons for concern.

The usage of the term in sports arose during the 1961 baseball season in which Roger Maris of the New York Yankees was threatening to break Babe Ruth's 34-year-old single-season home run record. Ruth had amassed 60 home runs in a season with only 154 games, but Maris was playing the first season in the American League's newly expanded 162-game season. Baseball Commissioner Ford Frick, a friend of Ruth's during the legendary slugger's lifetime, held a press conference to announce his "ruling" that should Maris take longer than 154 games both records would be acknowledged by Major League Baseball, but that some "distinctive mark" [his term] be placed next to Maris', which should be listed alongside Ruth's achievement in the "record books". The asterisk as such a mark was suggested at that time by New York Daily News sportswriter Dick Young, not Frick. The reality, however, was that MLB actually had no direct control over any record books until many years later, and it all was merely a suggestion on Frick's part. Within a few years the controversy died down and all prominent baseball record keepers listed Maris as the single-season record holder.

Nevertheless, the stigma of holding a tainted record remained with Maris for many years, and the concept of a real or figurative asterisk denoting less-than-accepted "official" records has become widely used in sports and other competitive endeavors. A 2001 TV movie about Maris's record-breaking season was called (pronounced sixty-one asterisk) in reference to the controversy.

Uproar over the integrity of baseball records and whether or not qualifications should be added to them arose again in the late 1990s, when a steroid-fueled power explosion led to the shattering of Maris' record. Even though it was obvious - and later admitted - by Mark McGwire that he was heavily on steroids when he hit 70 home runs in 1998, ruling authorities did nothing to the annoyance of many fans and sportswriters. Three years later self-confessed steroid-user Barry Bonds pushed that record out to 73, and fans once again began to call for an asterisk in the sport's record books.

Fans were especially critical and clamored louder for baseball to act during the 2007 season, as Bonds approached and later broke Hank Aaron's career home run record of 755.

After an investigation by MLB revealed the Houston Astros' involvement in a sign-stealing scheme during the 2017 season, where they won the World Series, fans appalled by what they perceived to be overly lenient discipline against the Astros players nicknamed the team the "Houston Asterisks".

In recent years, the asterisk has come into use on baseball scorecards to denote a "great defensive play."

By the end of the first decade of the 21st century, the association of baseball and its records with doping had become so notorious that the term "asterisk" had become firmly associated with doping in sport. In February 2011 the United States Olympic Committee and the Ad Council launched an anti-steroid campaign called "Play Asterisk Free" aimed at teens. The campaign, whose logo uses a heavy asterisk(✱), first launched in 2008 under the name Don't Be An Asterisk.

In cricket, it signifies a total number of runs scored by a batsman without losing his wicket; e.g. "107*" means "107 not out".

Where only the scores of the two batsmen that are currently in are being shown, an asterisk following a batsman's score indicates that he is due to face the next ball to be delivered.

When written before a player's name on a scorecard, it indicates the captain of the team.

It is also used on television when giving a career statistic during a match. For example, "47*" in a number of matches column means that the current game is the player's 47th.

During the first decades of the 21st century, the term asterisk to denote a tainted accomplishment[citation needed ] caught on in other sports first in North America and then, due in part to North American sports' widespread media exposure, around the world.

In some command line interfaces, such as the Unix shell and Microsoft's CMD, the asterisk is the wildcard character and stands for any string of characters. This is also known as a wildcard symbol. A common use of the wildcard is in searching for files on a computer. For instance, if a user wished to find a document called Document 1, search terms such as Doc* and D*ment* would return this file. Due to being a wildcard, they could also return files life Document 2 and (only the latter) Dark Knight Monument.jpg. Document* would in fact return any file that begins with Document, and D*ment* any file that began with D and had 'ment' somewhere in its name.

In some graphical user interfaces an asterisk is pre- or appended to the current working document name shown in a window's title bar to indicate that unsaved changes exist.

In many computing and Internet applications an asterisk, or another character, is displayed to indicate that a character of a password or other confidential information has been entered, without the risk of displaying the actual character.

In Commodore (and related) files systems, an asterisk appearing next to a filename in a directory listing denotes an improperly closed file, commonly called a "splat file".

In travel industry Global Distribution Systems, the asterisk is the display command to retrieve all or part of a Passenger Name Record.

In HTML web forms, an asterisk can be used to denote required fields.

Chat room etiquette calls on one asterisk to correct a misspelled word that has already been submitted. For example, one could post lck, then follow it with *luck or luck* (the placement of the * on the left or right is a matter of personal style) to correct the word's spelling, or if it's someone else that notices the mistake, they might also use *luck or luck*.
Enclosing a phrase between two asterisks is used to denote an action the user is "performing", e.g. *pulls out a paper*, although this usage is also common on forums, and less so on most chat rooms due to /me or similar commands. Hyphens (-action-) and double colons (::action::) as well as the operator /me are also used for similar purposes.

Adding machines and printing calculators

Some models of adding machines and printing calculators use the asterisk to denote the total, or the terminal sum or difference of an addition or subtraction sequence, respectively. The symbol is sometimes given on the printout to indicate this total.[citation needed ]

Many programming languages and calculators use the asterisk as a symbol for multiplication. It also has a number of special meanings in specific languages, for instance:

In some programming languages such as the C, C++, and Go programming languages, the asterisk is used to dereference or declare a pointer variable.

In the Common Lisp programming language, the names of global variables are conventionally set off with asterisks, *LIKE-THIS*.

In the Ada, Fortran, Perl, Python, Ruby programming languages, in some dialects of the Pascal programming language, and many others, a double asterisk is used to signify exponentiation: 5**3 is 5³ = 125.

In the Perl programming language, the asterisk is used to refer to the of all variables with a given name.

In the programming languages Ruby and Python, * has two specific uses. First, the unary * operator applied to a list object inside a function call will expand that list into the arguments of the function call. Second, a parameter preceded by * in the parameter list for a function will result in any extra positional parameters being aggregated into a tuple (Python) or array (Ruby), and likewise a parameter preceded by ** will result in any extra keyword parameters being aggregated into a dictionary (Python) or hash (Ruby).

In the APL language, the asterisk represents the exponential and exponentiation functions, with *X representing e, and Y*X representing Y.

In IBM Job Control Language, the asterisk has various functions, including in-stream data in the DD statement, the default print stream as SYSOUT=*, and as a self-reference in place of a procedure step name to refer to the same procedure step where it appears.

In Haskell, the asterisk represents the set of well-formed, fully applied types; that is, a 0-ary kind of types.

In many markup programming languages, putting text between two asterisks makes the text bold or italic. For example, *Hello world!* will often turn into "Hello world!" or "Hello world!".

In the B programming language and languages that borrow syntax from it, such as C, PHP, Java, or C#, comments in the source code (for information to people, ignored by the compiler) are marked by an asterisk combined with the slash:

/* This section displays message if user input was not valid
    (comment ignored by compiler) */

Some Pascal-like programming languages, for example, Object Pascal, Modula-2, Modula-3, and Oberon, as well as several other languages including ML, Wolfram Language ( Mathematica), AppleScript, OCaml, Standard ML, and Maple, use an asterisk combined with a parenthesis:

 (* Do not change this variable - it is used later
    (comment ignored by compiler) *)

CSS also uses the slash-star comment format.

Each computing language has its own way of handling comments; /* ... */ and similar notations are not universal.

In economics, the use of an asterisk after a letter indicating a variable such as price, output, or employment indicates that the variable is at its optimal level (that which is achieved in a perfect market situation). For instance, p* is the price level p when output y is at its corresponding optimal level of y*.

Also in international economics asterisks are commonly used to denote economic variables in a foreign country. So, for example, "p" is the price of the home good and "p*" is the price of the foreign good, etc.

In fluid mechanics an asterisk in superscript is sometimes used to mean a property at sonic speed.

Certain categories of character types in role-playing games are called splats, and the game supplements describing them are called splatbooks. This usage originated with the shorthand "*book" for this type of supplement to various World of Darkness games, such as Clanbook: Ventrue (for Vampire: The Masquerade) or Tribebook: Black Furies (for Werewolf: The Apocalypse), and this usage has spread to other games with similar character-type supplements. For example, Dungeons & Dragons Third Edition has had several lines of splatbooks: the "X & Y" series including Sword & Fist and Tome & Blood prior to the "3.5" revision, the "Complete X" series including Complete Warrior and Complete Divine, and the "Races of X" series including Races of Stone and Races of the Wild.

In many MUDs and MOOs, as well as "male", "female", and other more esoteric genders, there is a gender called "splat", which uses an asterisk to replace the letters that differ in standard English gender pronouns. For example, h* is used rather than him or her. Also, asterisks are used to signify doing an action, for example, "*action*".

Game show producer Mark Goodson used a six-pointed asterisk as his trademark. It is featured prominently on many set pieces from The Price Is Right.

Scrabble players put an asterisk after a word to indicate that an illegal play was made.

In human genetics, * is used to denote that someone is a member of a haplogroup and not any of its subclades (see * (haplogroup)).

In linguistics, an asterisk is placed before a word or phrase to indicate that it is not used, or there are no records of it being in use. This is used in several ways depending on what is being discussed. It may be used to indicate reconstructed words in proto-languages for which there are no records of the pronunciation, grammar and words.

In historical linguistics, the asterisk marks words or phrases that are not directly recorded in texts or other media, and that are therefore reconstructed on the basis of other linguistic material (see also comparative method).

In the following example, the * Proto-Germanic word ainlif is a reconstructed form.

A double asterisk indicates a form that would be expected according to a rule, but is not actually found. That is, it indicates a reconstructed form that is not found or used, and in place of which another form is found in actual usage:

For the plural, **kubar would be expected, but separate masculine plural akābir ‏‎ and feminine plural kubrayāt ‏‎ are found as irregular forms.

In most areas of linguistics, but especially in syntax, an asterisk in front of a word or phrase indicates that the word or phrase is not used because it is ungrammatical.

An asterisk before a parenthesis indicates that the lack of the word or phrase inside is ungrammatical, while an asterisk after the opening bracket of the parenthesis indicates that the existence of the word or phrase inside is ungrammatical.

go *(to) the station - Here, "go the station" would be ungrammatical.

go (*to) home - Here, "go to home" would be ungrammatical.

Since a word marked with an asterisk could mean either "unattested" or "impossible", it is important in some contexts to distinguish these meanings. In general, authors retain asterisks for "unattested", and prefix x, **, †, or ? for the latter meaning.[citation needed ] An alternative is to append the asterisk (or another symbol, possibly to differentiate between even more cases) at the end.[citation needed ]

In optimality theory, asterisks are used as "violation marks" in tableau cells to denote a violation of a constraint by an output form.

In phonetic transcription using the International Phonetic Alphabet, an asterisk was sometimes historically used to denote that the word it preceded was a proper noun. See this example from W. Perrett's 1921 transcription of Gottfried Keller's " Das Fähnlein der sieben Aufrechten":

ˈkɑinə ˈreːdə, virt ˈniçts daˈraˑus! zɑːktə *ˈheːdigər ˈkurts.

("Keine Rede, wird nichts daraus!" sagte Hediger kurz. )

This diacritic isn't often used.

The asterisk has many uses in mathematics. The following list highlights some common uses and is not exhaustive.

stand-alone

An arbitrary point in some set. Seen, for example, when computing Riemann sums or when contracting a simply connected group to the singleton set { ∗ }.

as a unary operator, denoted in prefix notation

as a unary operator, written as a subscript

as a unary operator, written as a superscript

as a binary operator, in infix notation

The asterisk is used in all branches of mathematics to designate a correspondence between two quantities denoted by the same letter - one with the asterisk and one without.

In fine mathematical typography, the Unicode character ∗ ASTERISK OPERATOR (in HTML, &lowast;) is available. This character also appeared in the position of the regular asterisk in the PostScript symbol character set in the Symbol font included with Windows and Macintosh operating systems and with many printers. It should be used in fine typography for a large asterisk that lines up with the other mathematical operators.

In the Geneva Bible and the King James Bible, an asterisk is used to indicate a marginal comment or scripture reference.

In the Leeser Bible, an asterisk is used to mark off the seven subdivisions of the weekly Torah portion. It is also used to mark the few verses to be repeated by the reader of the Haftara.

In American printings of the Book of Common Prayer, an asterisk is used to divide a verse of a Psalm in two portions for responsive reading. British printings use a spaced colon (" : ") for the same purpose.

In pointed psalms, an asterisk is used to denote a break or breath.

A Star of Life, a six-bar star overlaid with the Rod of Asclepius (the symbol of health), may be used as an alternative to cross or crescent symbols on ambulances.

In many scientific publications, the asterisk is employed as a shorthand to denote the statistical significance of results when testing hypotheses. When the likelihood that a result occurred by chance alone is below a certain level, one or more asterisks are displayed. Popular significance levels are <0.05 (*), <0.01 (**), and <0.001 (***).

On a tone dialling telephone keypad, the asterisk (called star) is one of the two special keys (the other is the 'square key - almost invariably replaced by the number sign # (called 'pound sign' (US), 'hash' (other countries), or 'hex'), and is found to the left of the zero.) They are used to navigate menus in systems such as voice mail, or in vertical service codes.

The asterisk is used to call out a footnote, especially when there is only one on the page. Less commonly, multiple asterisks are used to denote different footnotes on a page (i.e., *, **, ***). Typically, an asterisk is positioned after a word or phrase and preceding its accompanying footnote. Other characters are also used for this purpose, such as dagger (†, ‡) or superscript letters and numbers (as in Wikipedia). In marketing and advertising, asterisks or other symbols are used to refer readers discreetly to terms or conditions for a certain statement, the "small print".

In English-language typography the asterisk is placed after all other punctuation marks (for example, commas, colons, or periods) except for the dash.

Three spaced asterisks centered on a page is called a dinkus and may represent a jump to a different scene, thought, or section.

A group of three asterisks arranged in a triangular formation is called an asterism. It may be used instead of a name on a title page.

One or more asterisks may be used as censorship over all or part of a word.

Asterisks are sometimes used as an alternative to typographical bullets to indicate items of a list.

Asterisks can be used in textual media to represent *emphasis* when bold or italic text is not available (e.g., Twitter, text messaging).

Asterisks may denote conversational repair, or corrections to misspelling or misstatements in previous electronic messages, particularly when replacement or retraction of a previous writing is not possible, such as with "immediate delivery" messages or "instant messages" that can not be edited. Usually this takes the form of a message consisting solely of the corrected text, with an asterisk placed before (or after) the correction. For example, one might send a message reading "*morning" or "morning*" to correct the misspelling in the message "I had a good mroning".[citation needed ]

Bounding asterisks as "a kind of self-describing stage direction", as linguist Ben Zimmer has put it. For example, in "Another gas station robbery *sigh*", the writer uses *sigh* to express disappointment (but does not necessarily literally sigh).

The Unicode standard has a variety of asterisk-like characters, compared in the table below. (Characters will display differently in different browsers and fonts.) The reason there are so many is chiefly because of the controversial[citation needed ] decision to include in Unicode the entire Zapf Dingbats symbol font.

Asterisk

Asterisk operator

Heavy asterisk

Small asterisk

Full-width asterisk

Open-centre asterisk

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The asterisk ( *), from Late Latin asteriscus, from Ancient Greek ἀστερίσκος , asteriskos, "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star. Computer scientists and mathematicians often vocalize it as star (as, for example, in the A* search algorithm or ).

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Asterix - the first French satellite - named by the press after popular French comics character Astérix

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Asterix - the first French satellite - named by the press after popular French comics character Astérix

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Astérix or A-1 (initially conceptualized as FR.2 or FR-2) is the first French satellite. It was launched on 26 November 1965 by a Diamant A rocket from the CIEES launch site at Hammaguir, Algeria. With Astérix, France became the sixth country to have an artificial satellite and the third country to launch a satellite on its own rocket. Its main purpose was to test the Diamant launcher, though it was also designed to study the ionosphere. Astérix continues to orbit Earth as of 2023 and is expected to remain in orbit for centuries.

The French space agencies Centre national d'études spatiales (CNES) and Centre national d'études des télécommunications (CNET) were developing Astérix concurrent with FR-1, another satellite, as early as 1963. FR-1 was the first step of an ambitious French plan to launch six FR-series satellites, each meant to study a different aspect of the Earth's atmosphere. FR-1 was generally designed to study the Earth's magnetic and electric fields in the ionosphere and magnetosphere. Astérix, ultimately France's first satellite, was initially conceptualized as the second FR satellite under the name FR-2. Like FR-1, FR-2 would study the ionosphere. FR-3 was to be a "scaled-up" version of FR-2, with FR-4 to carry instruments measuring hydrogen distribution in the upper atmosphere, FR-5 to study "magnetic impulses" and serve as a platform for future research, and FR-6 to be a solar-stabilized spacecraft with final payload to be determined based on experimental results from its antecedents.

Initial plans called for a late 1964 or early 1965 launch of FR-1, with Astérix's launch scheduled for early 1965. It appears Astérix was put into orbit prior to FR-1 because Charles de Gaulle and CNES wanted France to become the third space power by launching an independently-developed satellite on a French launcher, a propaganda coup for French exceptionalism during the Cold War.

France managed to design, construct, and launch Astérix and FR-1 relatively quickly thanks to three related factors: postwar knowledge gained from Nazi scientists and their work on the V-2 rocket; France's independent development of nuclear IRBM launchers including the Saphir rocket, a precursor to Diamant; and France's collaborative civilian research with the United States (through NASA) and other European countries (through CERN and ESRO).

Measuring approximately 55 centimetres (22 in) in diameter and 55 centimetres high, Astérix's exterior casing is made of fiberglass and resembles a top. Its black stripes purportedly provide passive solar gain. Equipped with accelerometers measuring vertical and horizontal movement and angular velocity, a radio beacon, radar transponder, thermometer, and telemetry transmitters, the satellite was designed to report its position back to Earth. It is unclear whether Astérix was capable of making ionospheric measurements as originally planned.

The satellite was originally designated A-1, as the French Army's first satellite, but later renamed by the press after popular French comics character Astérix. The names Zébulon and Zebby, after another cartoon character from the French children's television program Le Manège enchanté, were also considered.

Specifications

France carried out two suborbital Astérix prototype flights on 31 May and 3 June 1965 using Rubis rockets from the CIEES launch complex Bacchus at Hammaguir, Algeria.

Astérix was launched on 26 November 1965 by a Diamant A rocket from the CIEES launch complex Brigitte/A at Hammaguir. The Diamant launcher measured 19 metres (62 ft) tall and weighed 18 tonnes (18 long tons; 20 short tons), and was filled with a mix of turpentine and nitric acid fuel. The payload fairing ejected from the rocket ten minutes after launch, during which the satellite's telemetry equipment was damaged. Depending on the source, due to this damage Astérix either failed to transmit any signals, or stopped transmitting them after two days or 111 days. Nevertheless, American radar scans confirmed the satellite successfully entered orbit.

With Astérix, France became the sixth country to have an artificial satellite in orbit after the USSR (, 1957), the United States (, 1958), the United Kingdom (, 1962), Canada (, 1962), and Italy (, 1964). France also became the third country after the USSR and US to launch a satellite on its own rocket: the British, Canadian, and Italian satellites were launched on American rockets.

Astérix remains in orbit as of 2023. Due to the relatively high altitude of its orbit, it is not expected to re-enter Earth's atmosphere for several centuries.

The Musée de l'air et de l'espace in Paris Le Bourget displays a prototype of the satellite, while the Cité de l'espace in Toulouse displays a replica.

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Astérix or A-1 (initially conceptualized as FR.2 or FR-2) is the first French satellite. It was launched on 26 November 1965 by a Diamant A rocket from the CIEES launch site at Hammaguir, Algeria. With Astérix, France became the sixth country to have an artificial satellite and the third country to launch a satellite on its own rocket.

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The National Centre for Space Studies (CNES; French: Centre national d'études spatiales)

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The National Centre for Space Studies (CNES; French: Centre national d'études spatiales)

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The National Centre for Space Studies ( CNES; French: Centre national d'études spatiales) is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and Research.

It operates from the Toulouse Space Centre and the Guiana Space Centre, but also has payloads launched from space centres operated by other countries. The president of CNES is Philippe Baptiste. CNES is a member of Institute of Space, its Applications and Technologies. It is Europe's largest and most important national organization of its type.

CNES was established under President Charles de Gaulle in 1961. It is the world's third oldest space agency, after the Soviet space program (Russia), and NASA (United States). CNES was responsible for the training of French astronauts, until the last active CNES astronauts transferred to the European Space Agency in 2001.

As of January 2015, CNES is working with Germany and a few other governments to start a modest research effort with the hope to propose a LOX/ methane reusable launch vehicle by mid-2015. If built, flight testing would likely not start before approximately 2026. The design objective is to reduce both the cost and duration of reusable vehicle refurbishment, and is partially motivated by the pressure of lower-cost competitive options with newer technological capabilities not found in the Ariane 6.

CNES concentrates on five areas:

Access to space

Civil applications of space

Sustainable development

Science and technology research

Security and defence

France was the third space power (see Diamant) to achieve access to space after the USSR and USA, sharing technologies with Europe to develop the Ariane launcher family. Commercial competition in space is fierce, so launch services must be tailored to space operators' needs. The latest versions of the Ariane 5 launch vehicle can launch large satellites to geosynchronous orbit or perform dual launches-launching two full-size satellites with one rocket-while the other launch vehicles used for European payloads and commercial satellites-the European/Italian Vega and Russian Soyuz-2 -are small and medium-lift launchers, respectively.

CNES and its partners in Europe-through the Global Monitoring for Environment and Security initiative (GMES)-and around the world have put in place satellites dedicated to observing the land, oceans, and atmosphere, as well as to hazard and crisis management. The best-known are the SPOT satellites flying the Vegetation instrument, the Topex/Poseidon, Jason-1 and Jason-2 oceanography satellites, the Argos system, Envisat, and the Pleiades satellites.

CNES is taking part in the Galileo navigation programme alongside the European Union and the European Space Agency (ESA), and-in a wider international context-in the Cospas-Sarsat search-and-rescue system.

The aforementioned Galileo navigation programme, though intended primarily for civilian navigational use, has a military purpose as well, like the similar American Global Positioning System and Russian GLONASS satellite navigational systems.

In addition to Spot and the future Pleiades satellites, CNES is working for the defence community as prime contractor for the Helios photo-reconnaissance satellites.

Global Monitoring for Environment and Security -a joint initiative involving the EU, ESA, and national space agencies-pools space resources to monitor the environment and protect populations, though it also encompasses satellite support for armed forces on border patrol, maritime security, and peacekeeping missions.

France's contribution to the International Space Station is giving French scientists the opportunity to perform original experiments in microgravity. CNES is also studying formation flying, a technique whereby several satellites fly components of a much heavier and complex instrument in a close and tightly controlled configuration, with satellites being as close as tens of meters apart. CNES is studying formation flying as part of the Swedish-led PRISMA project and on its own with the Simbol-x x-ray telescope mission.

CNES currently collaborates with other space agencies on a number of projects, including orbital telescopes like INTErnational Gamma-Ray Astrophysics Laboratory, XMM-Newton, and COROT and space probes like Mars Express, Venus Express, Cassini-Huygens, and Rosetta. CNES has collaborated with NASA on missions like the Earth observation satellite PARASOL and the CALIPSO environment and weather satellite.

It has also collaborated with the Indian Space Agency ( ISRO) on the Megha-Tropiques Mission, which is studying the water cycle and how it has been impacted by climate change. CNES plays a major role in the ESA's Living Planet Programme of Earth observation satellites, having constructed the Soil Moisture and Ocean Salinity satellite.

In December 2006, CNES announced that it would publish its UFO archive online by late January or mid-February. Most of the 6,000 reports have been filed by the public and airline professionals. Jacques Arnould, an official for the French Space Agency, said that the data had accumulated over a 30-year period and that UFO sightings were often reported to the Gendarmerie.

In the last two decades of the 20th century, France was the only country whose government paid UFO investigators, employed by CNES's UFO section GEPAN, later known as SEPRA and now as GEIPAN.

On March 22, 2007, CNES released its UFO files to the public through its website. The 100,000 pages of witness testimony, photographs, film footage, and audiotapes are an accumulation of over 1,600 sightings since 1954 and will include all future UFO reports obtained by the agency, through its GEIPAN unit.

The CNES has several tracking stations. A partial list follows:

1. ^ Maurice Vaïsse (dir.), La IVth République face aux problèmes d'armement, proceedings of the conference held on 29 and 30 September 1997 at the Military Academy of the Center for Defense of studying history, ed. Association pour le développement et la diffusion de l'information militaire (ADDIM), Paris, 1998, p.561 ISBN 2-907341-63-4, 648 pages

2. ^ Wade, Mark. "Hammaguira". Astronautix. Archived from the original on September 7, 2016.

3. ^ Burgess, Colin; Dubbs, Chris (2007). Animals in Space: From Research Rockets to the Space Shuttle. Berlin: Springer Science & Business Media. pp. 227-228. ISBN 978-0-387-36053-9.

4. ^ "Security Service" (PDF) (Press release). Paris: European Space Agency. September 2016. Archived from the original (PDF) on 2018-05-01.

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National Centre for Space Studies - Wikipedia

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The National Centre for Space Studies ( CNES; French: Centre national d'études spatiales) is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and Research.

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Philae Spacecraft - The lander is named after the Philae obelisk, which bears a bilingual inscription and was used along with the Rosetta Stone to decipher Egyptian hieroglyphs.

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Philae Spacecraft - The lander is named after the Philae obelisk, which bears a bilingual inscription and was used along with the Rosetta Stone to decipher Egyptian hieroglyphs.

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Mission type

Comet lander

Operator

European Space Agency / DLR

COSPAR ID

2004-006C

Website

www.esa.int/rosetta

Mission duration

Planned: 1-6 weeks
Active: 12-14 November 2014
Hibernation: 15 November 2014 - 13 June 2015

Manufacturer

DLR / MPS / CNES / ASI

Launch mass

100 kg (220 lb)[1]

Payload mass

21 kg (46 lb)[1]

Dimensions

1 × 1 × 0.8 m (3.3 × 3.3 × 2.6 ft)[1]

Power

32 watts at 3 AU[2]

Launch date

2 March 2004, 07:17 UTC

Rocket

Ariane 5G+ V-158

Launch site

Kourou ELA-3

Contractor
Arianespace

Last contact

9 July 2015, 18:07 UTC

Landing date

12 November 2014, 17:32 UTC[3]

Landing site

Abydos[4]

Instruments

APXS

Alpha particle x-ray spectrometer

CIVA

Comet nucleus Infrared and Visible Analyser

CONSERT

Comet Nucleus Sounding Experiment by Radiowave Transmission

COSAC

Cometary Sampling and Composition

MUPUS

Multi-purpose Sensors for Surface and Subsurface Science

PTOLEMY

Gas chromatograph and medium resolution mass spectrometer

ROLIS

Rosetta Lander Imaging System

ROMAP

Rosetta lander Magnetometer and Plasma monitor

SD2

Sampling, Drilling and Distribution

SESAME

Surface Electric Sounding and Acoustic Monitoring Experiment[5]

CASSE

Comet Acoustic Surface Sounding Experiment

DIM

Dust Impact Monitor

PP

Permittivity Probe

Philae ( or ) is a robotic European Space Agency lander that accompanied the Rosetta spacecraft until it separated to land on comet 67P/Churyumov-Gerasimenko, ten years and eight months after departing Earth. On 12 November 2014, touched down on the comet, but it bounced when its anchoring harpoons failed to deploy and a thruster designed to hold the probe to the surface did not fire. After bouncing off the surface twice, Philae achieved the first-ever "soft" (nondestructive) landing on a comet nucleus, although the lander's final, uncontrolled touchdown left it in a non-optimal location and orientation.

Despite the landing problems, the probe's instruments obtained the first images from a comet's surface. Several of the instruments on Philae made the first direct analysis of a comet, sending back data that would be analysed to determine the composition of the surface. In October 2020, scientific journal Nature published an article which revealed what it was determined Philae had discovered while it was operational on the surface of 67P/Churyumov-Gerasimenko.

On 15 November 2014 Philae entered safe mode, or hibernation, after its batteries ran down due to reduced sunlight and an off-nominal spacecraft orientation at the crash site. Mission controllers hoped that additional sunlight on the solar panels might be sufficient to reboot the lander. Philae communicated sporadically with Rosetta from 13 June to 9 July 2015, but contact was then lost. The lander's location was known to within a few tens of metres but it could not be seen. Its location was finally identified in photographs taken by Rosetta on 2 September 2016 as the orbiter was sent on orbits closer to the comet. The now-silent Philae was lying on its side in a deep crack in the shadow of a cliff. Knowledge of its location would help in interpretation of the images it had sent. On 30 September 2016, the Rosetta spacecraft ended its mission by crashing in the comet's Ma'at region.

The lander is named after the Philae obelisk, which bears a bilingual inscription and was used along with the Rosetta Stone to decipher Egyptian hieroglyphs. Philae was monitored and operated from DLR's Lander Control Center in Cologne, Germany.

Philae's mission was to land successfully on the surface of a comet, attach itself, and transmit data about the comet's composition. The Rosetta spacecraft and Philae lander were launched on an Ariane 5G+ rocket from French Guiana on 2 March 2004, 07:17 UTC, and travelled for 3,907 days (10.7 years) to Churyumov-Gerasimenko. Unlike the Deep Impact probe, which by design struck comet Tempel 1's nucleus on 4 July 2005, Philae is not an impactor. Some of the instruments on the lander were used for the first time as autonomous systems during the Mars flyby on 25 February 2007. CIVA, one of the camera systems, returned some images while the Rosetta instruments were powered down, while ROMAP took measurements of the Martian magnetosphere. Most of the other instruments needed contact with the surface for analysis and stayed offline during the flyby. An optimistic estimate of mission length following touchdown was "four to five months".

The goals of the scientific mission have been summarised as follows:

"The scientific goals of its experiments focus on elemental, isotopic, molecular and mineralogical composition of the cometary material, the characterization of physical properties of the surface and subsurface material, the large-scale structure and the magnetic and plasma environment of the nucleus. In particular, surface and sub-surface samples will be acquired and sequentially analyzed by a suite of instruments. Measurements will be performed primarily during descent and along the first five days following touch-down."

Philae remained attached to the Rosetta spacecraft after rendezvousing with Churyumov-Gerasimenko on 6 August 2014. On 15 September 2014, ESA announced "Site J" on the smaller lobe of the comet as the lander's destination. Following an ESA public contest in October 2014, Site J was renamed Agilkia in honour of Agilkia Island.

A series of four go/no-go checks were performed on 11-12 November 2014. One of the final tests before detachment from Rosetta showed that the lander's cold-gas thruster was not working correctly, but the "go" was given anyway, as it could not be repaired. Philae detached from Rosetta on 12 November 2014 at 08:35 UTC SCET.

Philae's landing signal was received by Earth communication stations at 16:03 UTC after a 28-minute delay. Unknown to mission scientists at that time, the lander had bounced. It began performing scientific measurements while slowly moving away from the comet and coming back down, confusing the science team. Further analysis showed that it bounced twice.

Philae's first contact with the comet occurred at 15:34:04 UTC SCET. The probe rebounded off the comet's surface at 38 cm/s (15 in/s) and rose to an altitude of approximately 1 km (0.62 mi). For perspective, had the lander exceeded about 44 cm/s (17 in/s), it would have escaped the comet's gravity. After detecting the touchdown, Philae's reaction wheel was automatically powered off, resulting in its momentum being transferred back into the lander. This caused the vehicle to begin rotating every 13 seconds. During this first bounce, at 16:20 UTC SCET, the lander is thought to have struck a surface prominence, which slowed its rotation to once every 24 seconds and sent the craft tumbling. Philae touched down a second time at 17:25:26 UTC SCET and rebounded at 3 cm/s (1.2 in/s). The lander came to a final stop on the surface at 17:31:17 UTC SCET. It sits in rough terrain, apparently in the shadow of a nearby cliff or crater wall, and is canted at an angle of around 30 degrees, but is otherwise undamaged. Its final location was determined initially by analysis of data from CONSERT in combination with the comet shape model based on images from the Rosetta orbiter, and later precisely by direct imaging from Rosetta.

An analysis of telemetry indicated that the initial impact was softer than expected, that the harpoons had not deployed, and that the thruster had not fired. The harpoon propulsion system contained 0.3 grams of nitrocellulose, which was shown by Copenhagen Suborbitals in 2013 to be unreliable in a vacuum.

The primary battery was designed to power the instruments for about 60 hours. ESA expected that a secondary rechargeable battery would be partially filled by the solar panels attached to the outside of the lander, but the limited sunlight (90 minutes per 12.4-hour comet day) at the actual landing site was inadequate to maintain Philae's activities, at least in this phase of the comet's orbit.

On the morning of 14 November 2014, the battery charge was estimated to be only enough for continuing operations for the remainder of the day. After first obtaining data from instruments whose operation did not require mechanical movement, comprising about 80% of the planned initial science observations, both the MUPUS soil penetrator and the SD2 drill were commanded to deploy. Subsequently, MUPUS data as well as COSAC and Ptolemy data were returned. A final set of CONSERT data was also downlinked towards the end of operations. During the evening's transmission session, Philae was raised by 4 centimetres (1.6 in) and its body rotated 35 degrees to more favourably position the largest solar panel to capture the most sunlight in the future. Shortly afterwards, electrical power dwindled rapidly and all instruments were forced to shut down. The downlink rate slowed to a trickle before coming to a stop. Contact was lost on 15 November at 00:36 UTC.

The German Aerospace Center's lander manager Stephan Ulamec stated:

Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence ... This machine performed magnificently under tough conditions, and we can be fully proud of the incredible scientific success Philae has delivered.

Data from the SESAME instrument determined that, rather than being "soft and fluffy" as expected, Philae's first touchdown site held a large amount of water ice under a layer of granular material about 25 cm (9.8 in) deep. It found that the mechanical strength of the ice was high and that cometary activity in that region was low. At the final landing site, the MUPUS instrument was unable to hammer very far into the comet's surface, despite power being gradually increased. This area was determined to have the consistency of solid ice or pumice.

In the atmosphere of the comet, the COSAC instrument detected the presence of molecules containing carbon and hydrogen. Soil elements could not be assessed, because the lander was unable to drill into the comet surface, likely due to hard ice. The SD2 drill went through the necessary steps to deliver a surface sample to the COSAC instrument, but nothing entered the COSAC ovens.

Upon Philae's first touchdown on the comet's surface, COSAC measured material at the bottom of the vehicle, which was disturbed by the landing, while the Ptolemy instrument measured material at the top of the vehicle. Sixteen organic compounds were detected, four of which were seen for the first time on a comet, including acetamide, acetone, methyl isocyanate and propionaldehyde.

On 13 June 2015 at 20:28 UTC, ground controllers received an 85-second transmission from Philae, forwarded by Rosetta, indicating that the lander was in good health and had sufficiently recharged its batteries to come out of safe mode. Philae sent historical data indicating that although it had been operating earlier than 13 June 2015, it had been unable to contact Rosetta before that date. The lander reported that it was operating with 24 watts of electrical power at −35 °C (−31 °F).

A new contact between Rosetta and Philae was confirmed on 19 June 2015. The first signal was received on the ground from Rosetta at 13:37 UTC, while a second signal was received at 13:54 UTC. These contacts lasted about two minutes each and delivered additional status data. By 26 June 2015, there had been a total of seven intermittent contacts between the lander and orbiter. There were two opportunities for contact between the two spacecraft each Earth day, but their duration and quality depended on the orientation of the transmitting antenna on Philae and the location of Rosetta along its trajectory around the comet. Similarly, as the comet rotated, Philae was not always in sunlight and thus not always generating enough power via its solar panels to receive and transmit signals. ESA controllers continued to try to establish a stable contact duration of at least 50 minutes.

Had Philae landed at the planned site of Agilkia in November 2014, its mission would probably have ended in March 2015 due to the higher temperatures of that location as solar heating increased. As of June 2015, Philae's key remaining experiment was to drill into the comet's surface to determine its chemical composition. Ground controllers sent commands to power up the CONSERT radar instrument on 5 July 2015, but received no immediate response from the lander. Confirmation was eventually received on 9 July, when the lander transmitted measurement data from the instrument.

Immediately after its reawakening, housekeeping data suggested that the lander's systems were healthy, and mission control uploaded commands for Rosetta to establish a new orbit and nadir so as to optimize communications, diagnostics, and enable new science investigations with Philae. However, controllers had difficulties establishing a stable communications connection with the lander. The situation was not helped by the need to keep Rosetta at a greater and safer distance from the comet as it became more active. The last communication was on 9 July 2015, and mission controllers were unable to instruct Philae to carry out new investigations. Subsequently, Philae failed to respond to further commands, and by January 2016, controllers acknowledged no further communications were likely.

On 27 July 2016, at 09:00 UTC, ESA switched off the Electrical Support System Processor Unit (ESS) onboard Rosetta, making further communications with Philae impossible.

The lander was located on 2 September 2016 by the narrow-angle camera aboard Rosetta as it was slowly making its descent to the comet. The search for the lander had been on-going during the Rosetta mission, using telemetry data and comparison of pictures taken before and after the lander's touchdown, looking for signs of the lander's specific reflectivity.

The search area was narrowed down to the most promising candidate, which was confirmed by a picture taken at a distance of 2.7 km (1.7 mi), clearly showing the lander. The lander sits on its side wedged into a dark crevice of the comet, explaining the lack of electrical power and proper communication with the probe. Knowing its exact location provides information needed to put Philae's two days of science into proper context.

The lander was designed to deploy from the main spacecraft body and descend from an orbit of 22.5 kilometres (14 mi) along a ballistic trajectory. It would touch down on the comet's surface at a velocity of around 1 metre per second (3.6 km/h; 2.2 mph). The legs were designed to dampen the initial impact to avoid bouncing as the comet's escape velocity is only around 1 m/s (3.6 km/h; 2.2 mph), and the impact energy was intended to drive ice screws into the surface. Philae was to then fire a harpoon into the surface at 70 m/s (250 km/h; 160 mph) to anchor itself. A thruster on top of Philae was to have fired to lessen the bounce upon impact and to reduce the recoil from harpoon firing. During the landing, the harpoons did not fire and the thruster failed to operate, leading to a multiple-contact landing.

Communications with Earth used the Rosetta orbiter as a relay station to reduce the electrical power needed. The mission duration on the surface was planned to be at least one week, but an extended mission lasting months was considered possible.[citation needed ]

The main structure of the lander is made from carbon fiber, shaped into a plate maintaining mechanical stability, a platform for the science instruments, and a hexagonal "sandwich" to connect all the parts. The total mass is about 100 kilograms (220 lb). Its exterior is covered with solar cells for power generation.

The Rosetta mission was originally planned to rendezvous with the comet 46P/Wirtanen. A failure in a previous Ariane 5 launch vehicle closed the launch window to reach the comet with the same rocket. It resulted in a change in target to the comet 67P/Churyumov-Gerasimenko. The larger mass of Churyumov-Gerasimenko and the resulting increased impact velocity required that the landing gear of the lander be strengthened.

Philae's power management was planned for two phases. In the first phase, the lander operated solely on battery power. In the second phase, it was to run on backup batteries recharged by solar cells.

The power subsystem comprises two batteries: a non-rechargeable primary 1000 watt-hour battery to provide power for the first 60 hours and a secondary 140 watt-hour battery recharged by the solar panels to be used after the primary is exhausted. The solar panels cover 2.2 square metres (24 sq ft) and were designed to deliver up to 32 watts at a distance of 3 AU from the Sun.

The science payload of the lander consists of ten instruments totalling 26.7 kilograms (59 lb), making up just over one quarter of the mass of the lander.

The Alpha Particle X-ray Spectrometer detects alpha particles and X-rays, which provide information on the elemental composition of the comet's surface. The instrument is an improved version of the APXS on the Mars Pathfinder.

CIVA

The Comet Nucleus Infrared and Visible Analyser (sometimes given as ÇIVA) is a group of seven identical cameras used to take panoramic pictures of the surface plus a visible-light microscope and an infrared spectrometer. The panoramic cameras (CIVA-P) are arranged on the sides of the lander at 60° intervals: five mono imagers and two others making up a stereo imager. Each camera has a 1024×1024 pixel CCD detector. The microscope and spectrometer (CIVA-M) are mounted on the base of the lander, and are used to analyse the composition, texture and albedo (reflectivity) of samples collected from the surface.

The COmet Nucleus Sounding Experiment by Radiowave Transmission used electromagnetic wave propagation to determine the comet's internal structure. A radar on Rosetta transmitted a signal through the nucleus to be received by a detector on Philae.

COSAC

The COmetary SAmpling and Composition instrument is a combined gas chromatograph and time-of-flight mass spectrometer to perform analysis of soil samples and determine the content of volatile components.

MUPUS

The MUlti-PUrpose Sensors for Surface and Sub-Surface Science instrument measured the density, thermal and mechanical properties of the comet's surface.

Ptolemy

An instrument measuring stable isotope ratios of key volatiles on the comet's nucleus.

ROLIS

The Rosetta Lander Imaging System is a CCD camera used to obtain high-resolution images during descent and stereo panoramic images of areas sampled by other instruments. The CCD detector consists of 1024×1024 pixels.

ROMAP

The Rosetta Lander Magnetometer and Plasma Monitor is a magnetometer and plasma sensor to study the nucleus' magnetic field and its interactions with the solar wind.

SD2

The Sampling, Drilling and Distribution system obtains soil samples from the comet and transfers them to the Ptolemy, COSAC, and CIVA instruments for in-situ analysis. SD2 contains four primary subsystems: drill, ovens, carousel, and volume checker. The drill system, made of steel and titanium, is capable of drilling to a depth of 230 mm (9.1 in), deploying a probe to collect samples, and delivering samples to the ovens. There are a total of 26 platinum ovens to heat samples-10 medium temperature ovens at 180 °C (356 °F) and 16 high temperature ovens at 800 °C (1,470 °F)-and one oven to clear the drill bit for reuse. The ovens are mounted on a rotating carousel that delivers the active oven to the appropriate instrument. The electromechanical volume checker determines how much material was deposited into an oven, and may be used to evenly distribute material on CIVA's optical windows. Development of SD2 was led by the Italian Space Agency with contributions by prime contractor Tecnospazio S.p.A. (now Selex ES S.p.A.) in charge of the system design and overall integration; the Italian company Tecnomare S.p.A., owned by Eni S.p.A., in charge of the design, development, and testing of the drilling/sampling tool and the volume checker; Media Lario; and Dallara. The instrument's principal investigator is Amalia Ercoli-Finzi (Politecnico di Milano).

SESAME

The Surface Electric Sounding and Acoustic Monitoring Experiments used three instruments to measure properties of the comet's outer layers. The Cometary Acoustic Sounding Surface Experiment (CASSE) measures the way in which sound travels through the surface. The Permittivity Probe (PP) investigates its electrical characteristics, and the Dust Impact Monitor (DIM) measures dust falling back to the surface.

On October 28, 2020, it was reported that Philae had discovered, among other things, "low-strength primitive ice inside cometary boulders." This also included primitive water ice from the comet's estimated formation 4.5 billion years prior. This occurred primarily at the site of Philae's second touchdown onto the 67P/Churyumov-Gerasimenko, where the spacecraft successfully produced four distinct surface contacts on two adjoining cometary boulders. Philae was also able to drill 0.25 metres into the comet's boulder ice.

Austria

The Austrian Space Research Institute developed the lander's anchor and two sensors within MUPUS, which are integrated into the anchor tips.

Belgium

The Belgian Institute for Space Aeronomy (BIRA) cooperated with different partners to build one of the sensors (DFMS) of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument. The Belgian Institute for Space Aeronomy (BIRA) and Royal Observatory of Belgium (ROB) provided information about the space weather conditions at Rosetta to support the landing of Philae. The main concern was solar proton events.

Canada

Two Canadian companies played a role in the mission. SED Systems, located on the University of Saskatchewan campus in Saskatoon, built three ground stations that were used to communicate with the Rosetta spacecraft. ADGA-RHEA Group of Ottawa provided MOIS (Manufacturing and Operating Information Systems) software which supported the procedures and command sequences operations software.

Finland

The Finnish Meteorological Institute provided the memory of the Command, Data and Management System (CDMS) and the Permittivity Probe (PP).

France

The French Space Agency, together with some scientific laboratories (IAS, SA, LPG, LISA) provided the system's overall engineering, radiocommunications, battery assembly, CONSERT, CIVA and the ground segment (overall engineering and development/operation of the Scientific Operation & Navigation Centre).

Germany

The German Space Agency (DLR) has provided the structure, thermal subsystem, flywheel, the Active Descent System (procured by DLR but made in Switzerland), ROLIS, downward-looking camera, SESAME, acoustic sounding and seismic instrument for Philae. It has also managed the project and did the level product assurance. The University of Münster built MUPUS (it was designed and built in Space Research Centre of Polish Academy of Sciences ) and the Braunschweig University of Technology the ROMAP instrument. The Max Planck Institute for Solar System Research made the payload engineering, eject mechanism, landing gear, anchoring harpoon, central computer, COSAC, APXS and other subsystems. The institute has led development and construction of COSAC and DIM, a part of SESAME, as well as contributed to the deveplopment and construction of ROMAP.

Hungary

The Command and Data Management Subsystem (CDMS) designed in the Wigner Research Centre for Physics of the Hungarian Academy of Sciences jointly with the Space and Ground Facilities Ltd. (a spin-off company of the Wigner Research Centre for Physics). The Power Subsystem (PSS) designed in the Department of Broadband Infocommunications and Electromagnetic Theory at Budapest University of Technology and Economics. CDMS is the fault tolerant central computer of the lander, while PSS assures that the power coming from the batteries and solar arrays are properly handled, controls battery charging and manages the onboard power distribution.

Ireland

Captec Ltd., based in Malahide, provided the independent validation of mission critical software (independent software validation facility or SVF) and developed the software for the communications interface between the orbiter and the lander. Captec also provided engineering support to the prime contractor for the launch activities at Kourou. Space Technology Ireland Ltd. at Maynooth University has designed, constructed and tested the Electrical Support System Processor Unit (ESS) for the Rosetta mission. ESS stores, transmits and provides decoding for the command streams passing from the spacecraft to the lander and handles the data streams coming back from the scientific experiments on the lander to the spacecraft.

Italy

The Italian Space Agency (ASI) developed the SD2 instrument and the photovoltaic assembly. Italian Alenia Space was involved in the assembly, integration and testing of the probe, as well as several mechanical and electrical ground support equipment. The company also built the probe's S-band and X-band digital transponder, used for communications with Earth.

Netherlands

Moog Bradford (Heerle, The Netherlands) provided the Active Descent System, which guided and propelled the lander down to its landing zone. To accomplish the ADS, a strategic industrial team was formed with Bleuler-Baumer Mechanik in Switzerland.

Poland

The Space Research Centre of the Polish Academy of Sciences built the Multi-Purpose Sensors for Surface and Subsurface Science (MUPUS).

Spain

The GMV Spanish division has been responsible for the maintenance of the calculation tools to calculate the criteria of lighting and visibility necessary to decide the point of landing on the comet, as well as the possible trajectories of decline of the Philae module. Other important Spanish companies or educational institutions that have been contributed are as follows: INTA, Airbus Defence and Space Spanish division, other small companies also participated in subcontracted packages in structural mechanics and thermal control like AASpace (former Space Contact), and the Universidad Politécnica de Madrid.

Switzerland

The Swiss Centre for Electronics and Microtechnology developed CIVA.

United Kingdom

The Open University and the Rutherford Appleton Laboratory (RAL) developed PTOLEMY. RAL also constructed the blankets that kept the lander warm throughout its mission. Surrey Satellites Technology Ltd. (SSTL) constructed the momentum wheel for the lander. It stabilised the module during the descent and landing phases. Manufacturer e2v supplied the CIVA and Rolis camera systems used to film the descent and take images of samples, as well as three other camera systems.

The landing was featured heavily in social media, with the lander having an official Twitter account portraying a personification of the spacecraft. The hashtag "#CometLanding" gained widespread traction. A Livestream of the control centres was set up, as were multiple official and unofficial events around the world to follow Philae's landing on Churyumov-Gerasimenko. Various instruments on Philae were given their own Twitter accounts to announce news and science results.

Vangelis composed the music for the trio of music videos released by ESA to celebrate the first-ever attempted soft landing on a comet by ESA's Rosetta mission.

On 12 November 2014, the search engine Google featured a Google Doodle of Philae on its home page. On 31 December 2014, Google featured Philae again as part of its New Year's Eve 2014 Doodle.

Online comic author Randall Munroe wrote a live updating strip on his website on the day of the landing.

1. ^ Ulamec, S.; Espinasse, S.; Feuerbacher, B.; Hilchenbach, M.; Moura, D.; et al. (April 2006). "Rosetta Lander-Philae: Implications of an alternative mission". Acta Astronautica. 58 (8): 435-441. Bibcode:2006AcAau..58..435U. doi:10.1016/j.actaastro.2005.12.009.

2. Gilpin, Lyndsey (14 August 2014). "The tech behind the Rosetta comet chaser: From 3D printing to solar power to complex mapping". TechRepublic.

3. ^ Bauer, Markus (15 September 2014). "'J' Marks the Spot for Rosetta's Lander". European Space Agency.

4. Spotts, Pete (12 November 2014). "Will Philae successfully land on comet? Thruster trouble heightens drama". The Christian Science Monitor.

5. ^ Sutherland, Paul (14 August 2015). "Comet's fizzing all over during closest approach to the Sun". Space Exploration Network.

6. ^ Biele, J.; Ulamec, S.; Richter, L.; Kührt, E.; Knollenberg, J.; Möhlmann, D. (2009). "The Strength of Cometary Surface Material: Relevance of Deep Impact Results for Philae Landing on a Comet". In Käufl, Hans Ulrich; Sterken, Christiaan (eds.). Deep Impact as a World Observatory Event: Synergies in Space, Time, and Wavelength. Deep Impact as a World Observatory Event: Synergies in Space. ESO Astrophysics Symposia. Springer. p. 297. Bibcode:2009diwo.conf..285B. doi:10.1007/978-3-540-76959-0_38. ISBN 978-3-540-76958-3.

7. ^ Biele, Jens; Ulamec, Stephan (2013). Preparing for Landing on a Comet - The Rosetta Lander Philae (PDF). 44th Lunar and Planetary Science Conference. 18-22 March 2013. The Woodlands, Texas. Bibcode:2013LPI....44.1392B. LPI Contribution No. 1719.

8. ^ Bibring, Jean-Pierre; Lamy, P; Langevin, Y; Souufflot, A; Berthé, J; Borg, J; Poulet, F; Mottola, S (2007). "CIVA". Space Science Reviews. 138 (1-4): 397-412. Bibcode:2007SSRv..128..397B. doi:10.1007/s11214-006-9135-5.

9. ^ Andrews, D. J.; Barber, S. J.; Morse, A. D.; Sheridan, S.; Wright, I. P.; et al. (2006). Ptolemy: An Instrument aboard the Rosetta Lander Philae, to Unlock the Secrets of the Solar System (PDF). 37th Lunar and Planetary Science Conference. 13-17 March 2006. League City, Texas.

10. Marchesi, M.; Campaci, R.; Magnani, P.; Mugnuolo, R.; Nista, A.; et al. (2001). Comet sample acquisition for ROSETTA lander mission. 9th European Space Mechanisms and Tribology Symposium. 19-21 September 2001. Liège, Belgium. Bibcode:2001ESASP.480...91M.

11. "Active Descent System" (PDF). Moog Inc. Archived from the original (PDF) on 12 November 2014.

12. "The MUPUS Instrument for Rosetta mission to comet Churyumov-Gerasimenko". Laboratorium Mechatroniki i Robotyki Satelitarnej. 2014. Archived from the original on 2 January 2014.

13. ^ "12 November, 2014 A Space Probe landed on the Surface of a Comet for the first time in Space Research". Wigner Research Centre for Physics. 14 November 2014. Archived from the original on 3 March 2016.

14. ^ Alan Tovey (11 November 2014). "UK space industry behind Rosetta comet mission". The Telegraph.

15. ^ "Live updates: Rosetta mission comet landing". European Space Agency. 12 November 2014.

16. ^ "Call for Media Opportunities to follow Rosetta mission's historic comet landing". European Space Agency. 16 October 2014.

17. ^ Mukherjee, Trisha (30 December 2014). "Google doodle wraps up year in animated '2014 trending topics'". The Indian Express.

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Mission type Comet lander Operator European Space Agency / DLR COSPAR ID 2004-006C Website www.esa.int/rosetta Mission duration Planned: 1-6 weeksActive: 12-14 November 2014Hibernation: 15 November 2014 - 13 June 2015 Manufacturer DLR / MPS / CNES / ASI Launch mass 100 kg (220 lb)[1] Payload mass 21 kg (46 lb)[1]

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ASTERIX FROM THE ASTERIX COMICS - The "-ix" ending of both names of Asterix and Obelix (as well as all the other pseudo-Gaulish "-ix" names in the series) alludes to the "-rix" suffix (meaning "king", like "-rex" in Latin)

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ASTERIX FROM THE ASTERIX COMICS - The "-ix" ending of both names of Asterix and Obelix (as well as all the other pseudo-Gaulish "-ix" names in the series) alludes to the "-rix" suffix (meaning "king", like "-rex" in Latin)

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Asterix (; French: Astérix) is a fictional character and the titular hero of the French comic book series .

The series portrays him as a diminutive but fearless Gaulish warrior living in the time of Julius Caesar's Gallic Wars. Asterix was created in 1959 by writer René Goscinny and illustrator Albert Uderzo. Since then, thirty-five books in the series have been released, with Uderzo taking over writing duties after the death of Goscinny in 1977. Asterix has also appeared in several animated and live-action film adaptations of the series, and serves as the mascot of the amusement park Parc Astérix. Before that, he was also the mascot of the magazine .

Asterix is a diminutive but fearless and cunning warrior, ever eager for new adventures. He lives around 50 BC in a fictional village in northwest Armorica (a region of ancient Gaul mostly equivalent to modern Brittany). This village is celebrated as the only part of Gaul still not conquered by Julius Caesar and his Roman legions. The inhabitants of the village gain superhuman strength by drinking a magic potion prepared by the druid, Getafix (French: Panoramix). The village is surrounded by, on one side, the ocean, and on the other by four unlucky Roman garrisons, intended to keep a watchful eye and ensure that the Gauls do not get up to mischief. These camps are Compendium, Aquarium, Laudanum and Totorum.

Asterix' parents are former villagers who now live in the city of Condatum ( Rennes), and he has cousins in Britannia ( Britain). He shares his birthday with his clumsy, oversized, but extremely strong and good-hearted best friend, Obelix. Asterix is one of the smartest and most sensible members of the village, and so he is usually chosen for any dangerous, important or exotic mission. Unlike most of the other villagers, he does not start or join brawls for the fun of it, although he does enjoy a good fight when there's cause. He rarely resorts to weapons, preferring to rely on his wits, and when necessary, his (magic potion enhanced) fists - though he carries his shortsword with him at all times, he is shown to be an occasional swordsman at best. What he does for a living is never truly known, though he is often shown going on missions, quests, or hunting. InAsterix and the Cauldron, however, it is clearly stated that neither he nor Obelix have ever done anything of the sort to 'earn' money. Asterix is most often simply described as a warrior, which makes sense in light of the fact that most of the adventures he undertakes at some point require engaging an enemy.

Although no romantic interest has been introduced for Asterix yet, it seems obvious that Asterix is more susceptible than his best friend Obelix to the charms of women. Asterix seems 'lovestruck' after receiving a kiss from Panacea towards the end of Asterix the Legionary and remains so till the last strip. He also seems similarly affected by a kiss from Latraviata, the female protagonist in Asterix and the Actress, although then it seems that Latraviata's effect on Asterix may have gone deeper, as he reflects on her (or maybe something else) during the journey back to their village. Again, while many may agree that both Asterix and Obelix share the same feelings for the same woman, Panacea (judging from the way Asterix often looks at her, trusts her, obeys her, and even goes as far as to kiss her in a hypnotic trance) it may simply be an act of instinct rising out of loneliness, as both Asterix and Obelix do not often get close to women. In the film Asterix and Obelix: Mission Cleopatra, he becomes infatuated by Cleopatra's handmaiden Giemeakis (whose kiss proves to have a dramatic effect on Asterix, making him capable of superhuman feats without using the magic potion), but this is not based on anything from the original books.

An occasional running gag is that his age is 'indeterminate'. In the collection of adventures Asterix and the Class Act, one story about his birth is called "In 35 BC" with the note "Before Caesar", referring to the time Caesar's reign began, in October 49 BC. Also, in page 24 of Asterix and Obelix's Birthday: The Golden Book, Asterix's passport is shown, in which his date of birth is said to be LXXXV(85) BC. From this, Asterix's age can be placed approximately at 35 years.

One of Asterix's most recognizable features is his winged helmet, its wings often falling into positions that match his expressions. It closely resembles the winged helmet featured on packets of Gauloises cigarettes.

Asterix was first voiced by Guy Piérauld in a radio play that aired in 1960. In 1967, Roger Carel assumed the voice of Asterix in the animated film Asterix the Gaul, providing the character's voice in all subsequent animated films as well as videogames until his retirement. The 2018 animated film Asterix: The Secret of the Magic Potion starred Asterix's original live action film actor, Christian Clavier, as the voice of Asterix, and in subsequent appearances Asterix has been voiced by Jean-Claude Donda.

In English dubs, Asterix has been voiced by Lee Payant, Sean Barrett, Jack Beaber, Bill Oddie, Henry Winkler, Craig Charles, Paul Giamatti, Ken Kramer, Jack Whitehall, and Brian Bowles.

In the live-action adaptations of the series made since the late 1990s, Asterix was played by Christian Clavier (Asterix and Obelix take on Caesar and Asterix & Obelix: Mission Cleopatra) then Clovis Cornillac (Asterix at the Olympic Games) then Édouard Baer (Asterix and Obelix: God Save Britannia) and Guillaume Canet (Asterix & Obelix: The Middle Kingdom). Olaf Wijnants dubbed the English voice for the first two, while in the third film's dub, Asterix is voiced by Leslie Clack.

Asterix is referred to in The Adventures of Tintin, in the story Tintin and the Picaros, in which one of the revellers in the Carnaval wears an Asterix costume. The reverse happens in " Asterix the Legionary", where one of the Belgian soldiers wears Tintin's distinctive hairstyle, and in Asterix in Belgium, where two characters Thomson and Thompson from The Adventures of Tintin make a guest appearance.

The series is also referred to in Larry Gonick's The Cartoon History of the Universe Volume 2. Asterix, Obelix and Vitalstatistix appear in several panels depicting the historical invasion of Rome by the Gauls.

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Asterix (; French: Astérix) is a fictional character and the titular hero of the French comic book series . The series portrays him as a diminutive but fearless Gaulish warrior living in the time of Julius Caesar's Gallic Wars. Asterix was created in 1959 by writer René Goscinny and illustrator Albert Uderzo.

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OBELIX FROM THE ASTERIX COMICS (CARRYING A MENHIR)

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OBELIX FROM THE ASTERIX COMICS (CARRYING A MENHIR)

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Obelix (; French: Obélix) is a cartoon character in the French comic book series . He works as a menhir sculptor and deliveryman, and is Asterix's best friend. Obelix is noted for his obesity, the menhirs he carries around on his back and his superhuman strength. He fell into a cauldron of the Gauls' magic potion when he was a baby, causing him to be the only Gaul in Asterix's village who is in a permanent state of superhuman strength. Because of this already enormous strength, Obelix is not allowed to drink the magic potion ever again, a ban he regards as being tremendously unfair. Other characteristics are his simplemindedness, his love and care for his dog Dogmatix, his anger when someone refers to him as being "fat", his enthusiasm for hunting and eating wild boars, and beating up Romans. His catchphrase is: "Ils sont fous ces romains", which translates into "These Romans are crazy!", although he considers nearly every other nationality, even other Gauls, to be just as strange.

The character was portrayed by actor Gérard Depardieu in every Asterix live-action film until 2023's Asterix & Obelix: The Middle Kingdom.

Obelix is Asterix's closest friend (they even have the same birthday-although this is inconsistent with the comic Obelix and Co., where only Obelix's birthday is celebrated). He generally works as a menhir delivery man. His passions in life are hanging around with Asterix, fighting, hunting and eating wild boar, making and carrying his menhirs, and beating up Roman legionaries (and occasionally collecting their helmets). Obelix has a little dog named Dogmatix (Fr. Idéfix), whom he adores. His parents live now in Condate (as seen in Asterix and the Actress) and his distant cousin Metallurgix, a golden sickle maker, lives in Lutetia (as seen in Asterix and the Golden Sickle).

Obelix's favourite food is roast wild boar which he usually hunts with Asterix, but he has a voracious appetite, and will try eating nearly anything with few exceptions; in Asterix and Obelix All at Sea and Asterix in Britain he seems not to like boiled boar. In fact, he eats nuts and oysters in the shell, and is completely oblivious to drugs, spicy food and poison, possibly due to the permanent effects of the magic potion. However, when he consumes alcohol, he gets very drunk very quickly, as seen for example in Asterix in Britain where he enjoys sampling different barrels of wine trying to find a barrel containing magic potion, or in Asterix and the Laurel Wreath, where both he and chief Vitalstatistix get drunk during a banquet, much to the shame of the latter's wife Impedimenta. Although he has his own house, Obelix is occasionally shown staying overnight at Asterix's.

Obelix owns the quarry where he chisels the menhirs himself. It is never directly stated what the menhirs are used for, though it is hinted that they are just oversized knick-knacks; however they are probably a running-gag regarding the origins of the mystery surrounding Menhirs in ancient Europe, with the joke being that Obelix delivered them. Obelix usually trades the stones away for whatever he needs, resulting in the village having a literal field of menhirs.

Obelix is kind-hearted, but socially inept-possibly because his strength means that others have had to adapt to him instead of vice versa. He is still not completely aware of his own strength and almost invariably breaks any door he gently knocks on. He is frequently used as a human battering ram for opening locked doors or breaking through walls. Similarly, he is unaware that others do not share his superhuman strength, and shows great surprise when others are crushed by what he calls "a little menhir", or when Asterix attempts to explain to him that a small dog like Dogmatix cannot lift a menhir. He also has little interest in subjects of formal education or intellectual pursuits, since sheer strength usually solves his problems; he generally leaves any decisions to Asterix. However, Obelix is not completely stupid. In Asterix and the Normans he deduces from various clues that Cacofonix the bard has gone to Lutetia to pursue a career in popular music: this unusual display of intelligence on Obelix's part surprises Getafix. He also surprises Asterix in Asterix and the Black Gold by reeling off a dictionary definition of wild boar in conversation (including the Latin taxonomical classification). He can also be quite dangerous when angered.

While cheerfully violent and enjoying a good fight, Obelix is far from brutal or sadistic: he tends to view fighting as a game and is generally friendly and polite (to the point of inappropriate courtesy) towards his opponents. He extends this benevolence even towards the Romans, whom he rarely seems to view as oppressors but more as less-willing participants in his rough-housing. His other favored pastimes are dancing (which he apparently is very good at), and occasionally drinking goat's milk to excess (as he rarely imbibes in alcohol).

Like Asterix, Obelix is a bachelor, but he is easily smitten by a pretty face. He harbours a hopeless crush on Panacea, the daughter of Soporifix (one of the other villagers), and occasionally other young women, most notably Mrs. Geriatrix (which enrages her husband). However, one may think that he will eventually find a mate and have children since in Asterix and the Class Act, he is shown to be the founder of a long dynasty of French warriors that lasted well into the 20th century.

Obelix's trademark phrase is "These Romans are crazy" ("Ils sont fous ces romains": in the Italian translation, it is "Sono pazzi questi Romani", which can be shortened to S.P.Q.R., Rome's motto), although he has applied a variant of it to nearly every group he's met in his travels: "These Britons are crazy", "These Corsicans are crazy", etc. This remark is followed by him tapping his forehead. It is a parody of the quote "These Gauls are crazy", which Julius Caesar famously said while describing the Gauls' fighting style during his conquest of the region.[citation needed ]

Unlike the other villagers, Obelix has no need to drink the druid Getafix's magic potion that gives superhuman strength, because he fell into the cauldron as a baby and its effect on him became permanent. Obelix is tall and massive. He is about 6 feet 2 inches (188 cm) tall and he weighs more than 300 pounds (140 kg). The story of that incident is told in How Obelix Fell into the Magic Potion When he was a Little Boy. Since this effect was not intended or expected, Getafix refuses to allow him even one more drop except under the most dire circumstances (either out of fear for his life, or fear for the lives of others should the inattentive and uncoordinated strongman become any stronger), which annoys Obelix greatly. (In Asterix and Obelix All at Sea, it is revealed that too much of the potion can turn the drinker to stone; exactly how much is not known, but a whole cauldron will certainly do the trick. This appears to only work on grown people as Obelix did not turn to stone as a baby, or may simply occur after drinking an excessive amount while still under the effects of a previous dose). However, in Asterix and Cleopatra, Getafix gives him a few drops to open a door in the Great Pyramid's Labyrinth but he comments that he does not see much difference between "before and after the potion" though this is presumably because Obelix is used to accomplishing any physical task with ease.

Although it has been clearly stated by both Getafix (in Asterix the Gaul) and Asterix (in Asterix and the Laurel Wreath) that the magic potion does NOT grant invulnerability (Getafix has a potion for that but it is only mentioned in Asterix the Gaul), meaning that they could be injured by the Romans in their fights but their raw strength generally prevents the Romans getting the chance to do so, the same does not seem to be true of Obelix. He does not even notice when attackers attempt to knock him unconscious with blows to the head, when Roman spearheads are stuck in his bottom in Asterix in Corsica or when anyone else attempts to harm him in any way. This may imply that Obelix, either by stupidity or ignorance, simply does not notice or react to the pain that should be inflicted, or that the potion has enhanced his overall strength, since it has been shown to increase the drinker's endurance allowing them to run faster, to such a point where his muscles allow him to effortlessly absorb the attacks in question. Most of the occasions where Obelix demonstrates invulnerability include him being attacked physically rather than with sharp objects, as in Asterix and the Magic Carpet, when an arrow accidentally hits his bottom and he yells in agony, and thus showing that Obelix isn't above physical pain.

Obelix does sometimes display twisted views, especially when it comes to the relationship between the Gauls and the Romans. As far as he is concerned the more Romans he can beat up the better and nobody should deny him this, not even the "selfish" Roman victims themselves:

In Asterix in Britain, he dismisses the claim that the Romans have invaded Britain; he believes that the Britons dragged the Romans over there in order to have all the fun for themselves. During a rugby match, Obelix is bored until he sees how violent the game can get, and is overjoyed, recommending that they play rugby in Gaul.

In Asterix in Corsica, it is revealed that the villagers attack the Romans at least once a year in order to celebrate the Gaulish victory at Gergovia. When the Romans leave their camps in order to avoid the attacks, Obelix sees this behaviour as crazy and detrimental to their "friendly" relationship.

In Asterix and Obelix All at Sea, he has a dream (or nightmare as he puts it) in which the Romans pull out of Gaul. He's horrified at the idea of such a dream coming true. He also declares that the idea of peace with the Romans is offensive to the memory of Vercingetorix. Far more likely is the fact that peace will mean that he will not be able to bash the Romans anymore, a prospect he dreads. He then comments on the good "sense" of the Romans in attacking the village (although they were actually merely planning a parade to welcome an admiral).

The Roman civil war between Caesar and Pompey features in both Asterix the Legionary and Asterix and the Actress. When he witnesses a battle between Roman troops, Obelix murmurs "What a waste!". But this is not so much on the wasted lives as the fact that it means that he has fewer Romans to bash himself.

Albert Augier voiced Obelix in a 1960 radio play. For the animated films, he has been voiced by Jacques Morel in the first three, Pierre Tornade in all films during the '80s and '90s, as well as the videogames Asterix & Obelix XXL and Asterix & Obelix XXL 2: Mission: Las Vegum, Jacques Frantz in the 2006 film Asterix and the Vikings and the videogame Asterix at the Olympic Games, and currently Guillaume Briat since the 2014 film Asterix: The Mansions of the Gods. In the English dubs of the animated films, he has been voiced by Hal Brav, Michael Kilgarriff, Billy Kearns, Bernard Bresslaw, Rosey Grier, Howard Lew Lewis, Brad Garrett, C. Ernst Harth, and Nick Frost.

In the live action films, Gérard Depardieu plays Obelix, with Gilles Lellouche set to play the character in Asterix & Obelix: The Middle Kingdom. The English dubs for these films have featured Obelix's voice being provided by Terry Jones, Dominic Fumusa, and Paul Bandey.

Obelix's name is a pun on the French word obélisque ( obelisk, an ancient Egyptian stone pillar), suggested by his rotund physique and his habit of casually carrying heavy stone monuments ( Menhir) around with him. The word "obelisk" is also (in both French and English) a variant of the word obelus ( obèle), a typographical mark ("†") often found in a companion role to that of the asterisk, after which his friend Asterix is named.

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Obelix (; French: Obélix) is a cartoon character in the French comic book series . He works as a menhir sculptor and deliveryman, and is Asterix's best friend. Obelix is noted for his obesity, the menhirs he carries around on his back and his superhuman strength.

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"MENHIR CHAOS" - A REFERENCE TO THE ASTERIX COMICS (CHARACTER OBELIX CARRIES AROUND MENHIRS AND USES THEM FOR SQUASHING ROMAN SOLDIERS)

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"MENHIR CHAOS" - A REFERENCE TO THE ASTERIX COMICS (CHARACTER OBELIX CARRIES AROUND MENHIRS AND USES THEM FOR SQUASHING ROMAN SOLDIERS)

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Richard Buckminster Fuller (; July 12, 1895 - July 1, 1983) was an American architect, systems theorist, writer, designer, inventor, philosopher, and futurist. He styled his name as R. Buckminster Fuller in his writings, publishing more than 30 books and coining or popularizing such terms as " Spaceship Earth", " Dymaxion" (e.g., Dymaxion house, Dymaxion car, Dymaxion map), " ephemeralization", " synergetics", and " tensegrity".

Fuller developed numerous inventions, mainly architectural designs, and popularized the widely known geodesic dome; carbon molecules known as fullerenes were later named by scientists for their structural and mathematical resemblance to geodesic spheres. He also served as the second World President of Mensa International from 1974 to 1983.

Fuller was awarded 28 United States patents and many honorary doctorates. In 1960, he was awarded the Frank P. Brown Medal from The Franklin Institute. He was elected an honorary member of Phi Beta Kappa in 1967, on the occasion of the 50-year reunion of his Harvard class of 1917 (from which he was expelled in his first year). He was elected a Fellow of the American Academy of Arts and Sciences in 1968. The same year, he was elected into the National Academy of Design as an Associate member. He became a full Academician in 1970, and he received the Gold Medal award from the American Institute of Architects the same year. Also in 1970, Fuller received the title of Master Architect from Alpha Rho Chi (APX), the national fraternity for architecture and the allied arts. In 1976, he received the St. Louis Literary Award from the Saint Louis University Library Associates. In 1977, he received the Golden Plate Award of the American Academy of Achievement. He also received numerous other awards, including the Presidential Medal of Freedom, presented to him on February 23, 1983, by President Ronald Reagan.

Fuller c. 1910

Fuller was born on July 12, 1895, in Milton, Massachusetts, the son of Richard Buckminster Fuller and Caroline Wolcott Andrews, and grand-nephew of Margaret Fuller, an American journalist, critic, and women's rights advocate associated with the American transcendentalism movement. The unusual middle name, Buckminster, was an ancestral family name. As a child, Richard Buckminster Fuller tried numerous variations of his name. He used to sign his name differently each year in the guest register of his family summer vacation home at Bear Island, Maine. He finally settled on R. Buckminster Fuller.

Fuller spent much of his youth on Bear Island, in Penobscot Bay off the coast of Maine. He attended Froebelian Kindergarten. He was dissatisfied with the way geometry was taught in school, disagreeing with the notions that a chalk dot on the blackboard represented an "empty" mathematical point, or that a line could stretch off to infinity. To him these were illogical, and led to his work on synergetics. He often made items from materials he found in the woods, and sometimes made his own tools. He experimented with designing a new apparatus for human propulsion of small boats. By age 12, he had invented a 'push pull' system for propelling a rowboat by use of an inverted umbrella connected to the transom with a simple oar lock which allowed the user to face forward to point the boat toward its destination. Later in life, Fuller took exception to the term "invention".

Years later, he decided that this sort of experience had provided him with not only an interest in design, but also a habit of being familiar with and knowledgeable about the materials that his later projects would require. Fuller earned a machinist's certification, and knew how to use the press brake, stretch press, and other tools and equipment used in the sheet metal trade.

Fuller attended Milton Academy in Massachusetts, and after that began studying at Harvard College, where he was affiliated with Adams House. He was expelled from Harvard twice: first for spending all his money partying with a vaudeville troupe, and then, after having been readmitted, for his "irresponsibility and lack of interest". By his own appraisal, he was a non-conforming misfit in the fraternity environment.

Between his sessions at Harvard, Fuller worked in Canada as a mechanic in a textile mill, and later as a laborer in the meat-packing industry. He also served in the U.S. Navy in World War I, as a shipboard radio operator, as an editor of a publication, and as commander of the crash rescue boat USS Inca. After discharge, he worked again in the meat-packing industry, acquiring management experience. In 1917, he married Anne Hewlett. During the early 1920s, he and his father-in-law developed the Stockade Building System for producing lightweight, weatherproof, and fireproof housing-although the company would ultimately fail in 1927.

Fuller recalled 1927 as a pivotal year of his life. His daughter Alexandra had died in 1922 of complications from polio and spinal meningitis just before her fourth birthday. Barry Katz, a Stanford University scholar who wrote about Fuller, found signs that around this time in his life Fuller had developed depression and anxiety. Fuller dwelled on his daughter's death, suspecting that it was connected with the Fullers' damp and drafty living conditions. This provided motivation for Fuller's involvement in Stockade Building Systems, a business which aimed to provide affordable, efficient housing.

In 1927, at age 32, Fuller lost his job as president of Stockade. The Fuller family had no savings, and the birth of their daughter Allegra in 1927 added to the financial challenges. Fuller drank heavily and reflected upon the solution to his family's struggles on long walks around Chicago. During the autumn of 1927, Fuller contemplated suicide by drowning in Lake Michigan, so that his family could benefit from a life insurance payment.

Fuller said that he had experienced a profound incident which would provide direction and purpose for his life. He felt as though he was suspended several feet above the ground enclosed in a white sphere of light. A voice spoke directly to Fuller, and declared:

From now on you need never await temporal attestation to your thought. You think the truth. You do not have the right to eliminate yourself. You do not belong to you. You belong to the Universe. Your significance will remain forever obscure to you, but you may assume that you are fulfilling your role if you apply yourself to converting your experiences to the highest advantage of others.

Fuller stated that this experience led to a profound re-examination of his life. He ultimately chose to embark on "an experiment, to find what a single individual could contribute to changing the world and benefiting all humanity".

Speaking to audiences later in life, Fuller would frequently recount the story of his Lake Michigan experience, and its transformative impact on his life.

In 1927, Fuller resolved to think independently which included a commitment to "the search for the principles governing the universe and help advance the evolution of humanity in accordance with them ... finding ways of doing more with less to the end that all people everywhere can have more and more".[citation needed ] By 1928, Fuller was living in Greenwich Village and spending much of his time at the popular café Romany Marie's, where he had spent an evening in conversation with Marie and Eugene O'Neill several years earlier. Fuller accepted a job decorating the interior of the café in exchange for meals, giving informal lectures several times a week, and models of the Dymaxion house were exhibited at the café. Isamu Noguchi arrived during 1929- Constantin Brâncuși, an old friend of Marie's, had directed him there-and Noguchi and Fuller were soon collaborating on several projects, including the modeling of the Dymaxion car based on recent work by Aurel Persu. It was the beginning of their lifelong friendship.

Fuller taught at Black Mountain College in North Carolina during the summers of 1948 and 1949, serving as its Summer Institute director in 1949. Fuller had been shy and withdrawn, but he was persuaded to participate in a theatrical performance of Erik Satie's Le piège de Méduse produced by John Cage, who was also teaching at Black Mountain. During rehearsals, under the tutelage of Arthur Penn, then a student at Black Mountain, Fuller broke through his inhibitions to become confident as a performer and speaker.

At Black Mountain, with the support of a group of professors and students, he began reinventing a project that would make him famous: the geodesic dome. Although the geodesic dome had been created, built and awarded a German patent on June 19, 1925, by Dr. Walther Bauersfeld, Fuller was awarded United States patents. Fuller's patent application made no mention of Bauersfeld's self-supporting dome built some 26 years prior. Although Fuller undoubtedly popularized this type of structure he is mistakenly given credit for its design.

One of his early models was first constructed in 1945 at Bennington College in Vermont, where he lectured often. Although Bauersfeld's dome could support a full skin of concrete it was not until 1949 that Fuller erected a geodesic dome building that could sustain its own weight with no practical limits. It was 4.3 meters (14 feet) in diameter and constructed of aluminium aircraft tubing and a vinyl-plastic skin, in the form of an icosahedron. To prove his design, Fuller suspended from the structure's framework several students who had helped him build it. The U.S. government recognized the importance of this work, and employed his firm Geodesics, Inc. in Raleigh, North Carolina to make small domes for the Marines. Within a few years, there were thousands of such domes around the world.

Fuller's first "continuous tension - discontinuous compression" geodesic dome (full sphere in this case) was constructed at the University of Oregon Architecture School in 1959 with the help of students. These continuous tension - discontinuous compression structures featured single force compression members (no flexure or bending moments) that did not touch each other and were 'suspended' by the tensional members.

A 1933 Dymaxion prototype

For half of a century, Fuller developed many ideas, designs, and inventions, particularly regarding practical, inexpensive shelter and transportation. He documented his life, philosophy, and ideas scrupulously by a daily diary (later called the Dymaxion Chronofile), and by twenty-eight publications. Fuller financed some of his experiments with inherited funds, sometimes augmented by funds invested by his collaborators, one example being the Dymaxion car project.

The Montreal Biosphère by Buckminster Fuller, 1967

Fuller's home in Carbondale, Illinois

International recognition began with the success of huge geodesic domes during the 1950s. Fuller lectured at North Carolina State University in Raleigh in 1949, where he met James Fitzgibbon, who would become a close friend and colleague. Fitzgibbon was director of Geodesics, Inc. and Synergetics, Inc. the first licensees to design geodesic domes. Thomas C. Howard was lead designer, architect, and engineer for both companies. Richard Lewontin, a new faculty member in population genetics at North Carolina State University, provided Fuller with computer calculations for the lengths of the domes' edges.

Fuller began working with architect Shoji Sadao in 1954, together designing a hypothetical Dome over Manhattan in 1960, and in 1964 they co-founded the architectural firm Fuller & Sadao Inc., whose first project was to design the large geodesic dome for the U.S. Pavilion at Expo 67 in Montreal. This building is now the " Montreal Biosphère". In 1962, the artist and searcher John McHale wrote the first monograph on Fuller, published by George Braziller in New York.

After employing several Southern Illinois University Carbondale (SIU) graduate students to rebuild his models following an apartment fire in the summer of 1959, Fuller was recruited by longtime friend Harold Cohen to serve as a research professor of "design science exploration" at the institution's School of Art and Design. According to SIU architecture professor Jon Davey, the position was "unlike most faculty appointments ... more a celebrity role than a teaching job" in which Fuller offered few courses and was only stipulated to spend two months per year on campus. Nevertheless, his time in Carbondale was "extremely productive", and Fuller was promoted to university professor in 1968 and distinguished university professor in 1972.

Working as a designer, scientist, developer, and writer, he continued to lecture for many years around the world. He collaborated at SIU with John McHale. In 1965, they inaugurated the World Design Science Decade (1965 to 1975) at the meeting of the International Union of Architects in Paris, which was, in Fuller's own words, devoted to "applying the principles of science to solving the problems of humanity."

From 1972 until retiring as university professor emeritus in 1975, Fuller held a joint appointment at Southern Illinois University Edwardsville, where he had designed the dome for the campus Religious Center in 1971. During this period, he also held a joint fellowship at a consortium of Philadelphia-area institutions, including the University of Pennsylvania, Bryn Mawr College, Haverford College, Swarthmore College, and the University City Science Center; as a result of this affiliation, the University of Pennsylvania appointed him university professor emeritus in 1975.

Fuller believed human societies would soon rely mainly on renewable sources of energy, such as solar- and wind-derived electricity. He hoped for an age of "omni-successful education and sustenance of all humanity". Fuller referred to himself as "the property of universe" and during one radio interview he gave later in life, declared himself and his work "the property of all humanity". For his lifetime of work, the American Humanist Association named him the 1969 Humanist of the Year.

In 1976, Fuller was a key participant at UN Habitat I, the first UN forum on human settlements.

Fuller's last filmed interview took place on June 21, 1983, in which he spoke at Norman Foster's Royal Gold Medal for architecture ceremony. His speech can be watched in the archives of the AA School of Architecture, in which he spoke after Sir Robert Sainsbury's introductory speech and Foster's keynote address.

Gravestone (see Trim tab)

In the year of his death, Fuller described himself as follows:

Guinea Pig B:
I am now close to 88 and I am confident that the only thing important about me is that I am an average healthy human. I am also a living case history of a thoroughly documented, half-century, search-and-research project designed to discover what, if anything, an unknown, moneyless individual, with a dependent wife and newborn child, might be able to do effectively on behalf of all humanity that could not be accomplished by great nations, great religions or private enterprise, no matter how rich or powerfully armed.

Fuller died on July 1, 1983, 11 days before his 88th birthday. During the period leading up to his death, his wife had been lying comatose in a Los Angeles hospital, dying of cancer. It was while visiting her there that he exclaimed, at a certain point: "She is squeezing my hand!" He then stood up, had a heart attack, and died an hour later, at age 87. His wife of 66 years died 36 hours later. They are buried in Mount Auburn Cemetery in Cambridge, Massachusetts.

Buckminster Fuller was a Unitarian, and, like his grandfather Arthur Buckminster Fuller (brother of Margaret Fuller), a Unitarian minister. Fuller was also an early environmental activist, aware of Earth's finite resources, and promoted a principle he termed " ephemeralization", which, according to futurist and Fuller disciple Stewart Brand, was defined as "doing more with less". Resources and waste from crude, inefficient products could be recycled into making more valuable products, thus increasing the efficiency of the entire process. Fuller also coined the word synergetics, a catch-all term used broadly for communicating experiences using geometric concepts, and more specifically, the empirical study of systems in transformation; his focus was on total system behavior unpredicted by the behavior of any isolated components.

Fuller was a pioneer in thinking globally, and explored energy and material efficiency in the fields of architecture, engineering, and design. In his book Critical Path (1981) he cited the opinion of François de Chadenèdes (1920-1999) that petroleum, from the standpoint of its replacement cost in our current energy "budget" (essentially, the net incoming solar flux), had cost nature "over a million dollars" per U.S. gallon ($300,000 per litre) to produce. From this point of view, its use as a transportation fuel by people commuting to work represents a huge net loss compared to their actual earnings. An encapsulation quotation of his views might best be summed up as: "There is no energy crisis, only a crisis of ignorance."

Though Fuller was concerned about sustainability and human survival under the existing socioeconomic system, he remained optimistic about humanity's future. Defining wealth in terms of knowledge, as the "technological ability to protect, nurture, support, and accommodate all growth needs of life", his analysis of the condition of "Spaceship Earth" caused him to conclude that at a certain time during the 1970s, humanity had attained an unprecedented state. He was convinced that the accumulation of relevant knowledge, combined with the quantities of major recyclable resources that had already been extracted from the earth, had attained a critical level, such that competition for necessities had become unnecessary. Cooperation had become the optimum survival strategy. He declared: "selfishness is unnecessary and hence-forth unrationalizable ... War is obsolete." He criticized previous utopian schemes as too exclusive, and thought this was a major source of their failure. To work, he thought that a utopia needed to include everyone.

Fuller was influenced by Alfred Korzybski's idea of general semantics. In the 1950s, Fuller attended seminars and workshops organized by the Institute of General Semantics, and he delivered the annual Alfred Korzybski Memorial Lecture in 1955. Korzybski is mentioned in the Introduction of his book Synergetics. The two shared a remarkable amount of similarity in their formulations of general semantics.

In his 1970 book I Seem To Be a Verb, he wrote: "I live on Earth at present, and I don't know what I am. I know that I am not a category. I am not a thing-a noun. I seem to be a verb, an evolutionary process-an integral function of the universe."

Fuller wrote that the natural analytic geometry of the universe was based on arrays of tetrahedra. He developed this in several ways, from the close-packing of spheres and the number of compressive or tensile members required to stabilize an object in space. One confirming result was that the strongest possible homogeneous truss is cyclically tetrahedral.

He had become a guru of the design, architecture, and "alternative" communities, such as Drop City, the community of experimental artists to whom he awarded the 1966 "Dymaxion Award" for "poetically economic" domed living structures.

A geodesic sphere

Fuller was most famous for his lattice shell structures - geodesic domes, which have been used as parts of military radar stations, civic buildings, environmental protest camps, and exhibition attractions. An examination of the geodesic design by Walther Bauersfeld for the Zeiss-Planetarium, built some 28 years prior to Fuller's work, reveals that Fuller's Geodesic Dome patent (U.S. 2,682,235; awarded in 1954) is the same design as Bauersfeld's.

Their construction is based on extending some basic principles to build simple " tensegrity" structures (tetrahedron, octahedron, and the closest packing of spheres), making them lightweight and stable. The geodesic dome was a result of Fuller's exploration of nature's constructing principles to find design solutions. The Fuller Dome is referenced in the Hugo Award-winning novel Stand on Zanzibar by John Brunner, in which a geodesic dome is said to cover the entire island of Manhattan, and it floats on air due to the hot-air balloon effect of the large air-mass under the dome (and perhaps its construction of lightweight materials).

The Omni-Media-Transport:
With such a vehicle at our disposal, [Fuller] felt that human travel, like that of birds, would no longer be confined to airports, roads, and other bureaucratic boundaries, and that autonomous free-thinking human beings could live and prosper wherever they chose.

-Lloyd S. Sieden, Bucky Fuller's Universe, 2000
To his young daughter Allegra:
Fuller described the Dymaxion as a "zoom-mobile, explaining that it could hop off the road at will, fly about, then, as deftly as a bird, settle back into a place in traffic".

The Dymaxion car, c. 1933, artist Diego Rivera shown entering the car, carrying coat

The Dymaxion car was a vehicle designed by Fuller, featured prominently at Chicago's 1933-1934 Century of Progress World's Fair. During the Great Depression, Fuller formed the Dymaxion Corporation and built three prototypes with noted naval architect Starling Burgess and a team of 27 workmen - using donated money as well as a family inheritance.

Fuller associated the word Dymaxion, a blend of the words dynamic, maximum, and tension to sum up the goal of his study, "maximum gain of advantage from minimal energy input".

The Dymaxion was not an automobile but rather the 'ground-taxying mode' of a vehicle that might one day be designed to fly, land and drive - an "Omni-Medium Transport" for air, land and water. Fuller focused on the landing and taxiing qualities, and noted severe limitations in its handling. The team made improvements and refinements to the platform, and Fuller noted the Dymaxion "was an invention that could not be made available to the general public without considerable improvements".

The bodywork was aerodynamically designed for increased fuel efficiency and its platform featured a lightweight cromoly-steel hinged chassis, rear-mounted V8 engine, front-drive, and three-wheels. The vehicle was steered via the third wheel at the rear, capable of 90° steering lock. Able to steer in a tight circle, the Dymaxion often caused a sensation, bringing nearby traffic to a halt.

Shortly after launch, a prototype rolled over and crashed, killing the Dymaxion's driver and seriously injuring its passengers. Fuller blamed the accident on a second car that collided with the Dymaxion. Eyewitnesses reported, however, that the other car hit the Dymaxion only after it had begun to roll over.

Despite courting the interest of important figures from the auto industry, Fuller used his family inheritance to finish the second and third prototypes - eventually selling all three, dissolving Dymaxion Corporation and maintaining the Dymaxion was never intended as a commercial venture. One of the three original prototypes survives.

A Dymaxion house at The Henry Ford Museum in Dearborn, Michigan

Fuller's energy-efficient and inexpensive Dymaxion house garnered much interest, but only two prototypes were ever produced. Here the term "Dymaxion" is used in effect to signify a "radically strong and light tensegrity structure". One of Fuller's Dymaxion Houses is on display as a permanent exhibit at the Henry Ford Museum in Dearborn, Michigan. Designed and developed during the mid-1940s, this prototype is a round structure (not a dome), shaped something like the flattened "bell" of certain jellyfish. It has several innovative features, including revolving dresser drawers, and a fine-mist shower that reduces water consumption. According to Fuller biographer Steve Crooks, the house was designed to be delivered in two cylindrical packages, with interior color panels available at local dealers. A circular structure at the top of the house was designed to rotate around a central mast to use natural winds for cooling and air circulation.

Conceived nearly two decades earlier, and developed in Wichita, Kansas, the house was designed to be lightweight, adapted to windy climates, cheap to produce and easy to assemble. Because of its light weight and portability, the Dymaxion House was intended to be the ideal housing for individuals and families who wanted the option of easy mobility. The design included a "Go-Ahead-With-Life Room" stocked with maps, charts, and helpful tools for travel "through time and space". It was to be produced using factories, workers, and technologies that had produced World War II aircraft. It looked ultramodern at the time, built of metal, and sheathed in polished aluminum. The basic model enclosed 90 m ² (970 sq ft) of floor area. Due to publicity, there were many orders during the early Post-War years, but the company that Fuller and others had formed to produce the houses failed due to management problems.

In 1967, Fuller developed a concept for an offshore floating city named Triton City and published a report on the design the following year. Models of the city aroused the interest of President Lyndon B. Johnson who, after leaving office, had them placed in the Lyndon Baines Johnson Library and Museum.

In 1969, Fuller began the Otisco Project, named after its location in Otisco, New York. The project developed and demonstrated concrete spray with mesh-covered wireforms for producing large-scale, load-bearing spanning structures built on-site, without the use of pouring molds, other adjacent surfaces, or hoisting. The initial method used a circular concrete footing in which anchor posts were set. Tubes cut to length and with ends flattened were then bolted together to form a duodeca-rhombicahedron (22-sided hemisphere) geodesic structure with spans ranging to 60 feet (18 m). The form was then draped with layers of ¼-inch wire mesh attached by twist ties. Concrete was sprayed onto the structure, building up a solid layer which, when cured, would support additional concrete to be added by a variety of traditional means. Fuller referred to these buildings as monolithic ferroconcrete geodesic domes. However, the tubular frame form proved problematic for setting windows and doors. It was replaced by an iron rebar set vertically in the concrete footing and then bent inward and welded in place to create the dome's wireform structure and performed satisfactorily. Domes up to three stories tall built with this method proved to be remarkably strong. Other shapes such as cones, pyramids, and arches proved equally adaptable.

The project was enabled by a grant underwritten by Syracuse University and sponsored by U.S. Steel (rebar), the Johnson Wire Corp (mesh), and Portland Cement Company (concrete). The ability to build large complex load bearing concrete spanning structures in free space would open many possibilities in architecture, and is considered one of Fuller's greatest contributions.

Fuller, along with co-cartographer Shoji Sadao, also designed an alternative projection map, called the Dymaxion map. This was designed to show Earth's continents with minimum distortion when projected or printed on a flat surface.

In the 1960s, Fuller developed the World Game, a collaborative simulation game played on a 70-by-35-foot Dymaxion map, in which players attempt to solve world problems. The object of the simulation game is, in Fuller's words, to "make the world work, for 100% of humanity, in the shortest possible time, through spontaneous cooperation, without ecological offense or the disadvantage of anyone".

Buckminster Fuller wore thick- lensed spectacles to correct his extreme hyperopia, a condition that went undiagnosed for the first five years of his life. Fuller's hearing was damaged during his naval service in World War I and deteriorated during the 1960s. After experimenting with bullhorns as hearing aids during the mid-1960s, Fuller adopted electronic hearing aids from the 1970s onward.

In public appearances, Fuller always wore dark-colored suits, appearing like "an alert little clergyman". Previously, he had experimented with unconventional clothing immediately after his 1927 epiphany, but found that breaking social fashion customs made others devalue or dismiss his ideas. Fuller learned the importance of physical appearance as part of one's credibility, and decided to become "the invisible man" by dressing in clothes that would not draw attention to himself. With self-deprecating humor, Fuller described this black-suited appearance as resembling a "second-rate bank clerk".

Writer Guy Davenport met him in 1965 and described him thus:

He's a dwarf, with a worker's hands, all callouses and squared fingers. He carries an ear trumpet, of green plastic, with WORLD SERIES 1965 printed on it. His smile is golden and frequent; the man's temperament is angelic, and his energy is just a touch more than that of [Robert] Gallway (champeen runner, footballeur, and swimmer). One leg is shorter than the other, and the prescription shoe worn to correct the imbalance comes from a country doctor deep in the wilderness of Maine. Blue blazer, Khrushchev trousers, and a briefcase full of Japanese-made wonderments;

Following his global prominence from the 1960s onward, Fuller became a frequent flier, often crossing time zones to lecture. In the 1960s and 1970s, he wore three watches simultaneously; one for the time zone of his office at Southern Illinois University, one for the time zone of the location he would next visit, and one for the time zone he was currently in. In the 1970s, Fuller was only in 'homely' locations (his personal home in Carbondale, Illinois; his holiday retreat in Bear Island, Maine; and his daughter's home in Pacific Palisades, California) roughly 65 nights per year-the other 300 nights were spent in hotel beds in the locations he visited on his lecturing and consulting circuits.

In the 1920s, Fuller experimented with polyphasic sleep, which he called Dymaxion sleep. Inspired by the sleep habits of animals such as dogs and cats, Fuller worked until he was tired, and then slept short naps. This generally resulted in Fuller sleeping 30-minute naps every 6 hours. This allowed him "twenty-two thinking hours a day", which aided his work productivity. Fuller reportedly kept this Dymaxion sleep habit for two years, before quitting the routine because it conflicted with his business associates' sleep habits. Despite no longer personally partaking in the habit, in 1943 Fuller suggested Dymaxion sleep as a strategy that the United States could adopt to win World War II.

Despite only practicing true polyphasic sleep for a period during the 1920s, Fuller was known for his stamina throughout his life. He was described as "tireless" by Barry Farrell in Life magazine, who noted that Fuller stayed up all night replying to mail during Farrell's 1970 trip to Bear Island. In his seventies, Fuller generally slept for 5-8 hours per night.

Fuller documented his life copiously from 1915 to 1983, approximately 270 feet (82 m) of papers in a collection called the Dymaxion Chronofile. He also kept copies of all incoming and outgoing correspondence. The enormous R. Buckminster Fuller Collection is currently housed at Stanford University.

If somebody kept a very accurate record of a human being, going through the era from the Gay 90s, from a very different kind of world through the turn of the century-as far into the twentieth century as you might live. I decided to make myself a good case history of such a human being and it meant that I could not be judge of what was valid to put in or not. I must put everything in, so I started a very rigorous record.

Buckminster Fuller spoke and wrote in a unique style and said it was important to describe the world as accurately as possible. Fuller often created long run-on sentences and used unusual compound words (omniwell-informed, intertransformative, omni-interaccommodative, omniself-regenerative), as well as terms he himself invented. His style of speech was characterized by progressively rapid and breathless delivery and rambling digressions of thought, which Fuller described as "thinking out loud". The effect, combined with Fuller's dry voice and non-rhotic New England accent, was varyingly considered "hypnotic" or "overwhelming".

Fuller used the word Universe without the definite or indefinite article ( the or a) and always capitalized the word. Fuller wrote that "by Universe I mean: the aggregate of all humanity's consciously apprehended and communicated (to self or others) Experiences".

The words "down" and "up", according to Fuller, are awkward in that they refer to a planar concept of direction inconsistent with human experience. The words "in" and "out" should be used instead, he argued, because they better describe an object's relation to a gravitational center, the Earth. "I suggest to audiences that they say, 'I'm going "outstairs" and "instairs."' At first that sounds strange to them; They all laugh about it. But if they try saying in and out for a few days in fun, they find themselves beginning to realize that they are indeed going inward and outward in respect to the center of Earth, which is our Spaceship Earth. And for the first time they begin to feel real 'reality.'"

"World-around" is a term coined by Fuller to replace "worldwide". The general belief in a flat Earth died out in classical antiquity, so using "wide" is an anachronism when referring to the surface of the Earth-a spheroidal surface has area and encloses a volume but has no width. Fuller held that unthinking use of obsolete scientific ideas detracts from and misleads intuition. Other neologisms collectively invented by the Fuller family, according to Allegra Fuller Snyder, are the terms "sunsight" and "sunclipse", replacing "sunrise" and "sunset" to overturn the geocentric bias of most pre- Copernican celestial mechanics.

Fuller also invented the word "livingry", as opposed to weaponry (or "killingry"), to mean that which is in support of all human, plant, and Earth life. "The architectural profession-civil, naval, aeronautical, and astronautical-has always been the place where the most competent thinking is conducted regarding livingry, as opposed to weaponry."

As well as contributing significantly to the development of tensegrity technology, Fuller invented the term " tensegrity", a portmanteau of "tensional integrity". "Tensegrity describes a structural-relationship principle in which structural shape is guaranteed by the finitely closed, comprehensively continuous, tensional behaviors of the system and not by the discontinuous and exclusively local compressional member behaviors. Tensegrity provides the ability to yield increasingly without ultimately breaking or coming asunder."

" Dymaxion" is a portmanteau of "dynamic maximum tension". It was invented around 1929 by two admen at Marshall Field's department store in Chicago to describe Fuller's concept house, which was shown as part of a house of the future store display. They created the term using three words that Fuller used repeatedly to describe his design - dynamic, maximum, and tension.

Fuller also helped to popularize the concept of Spaceship Earth: "The most important fact about Spaceship Earth: an instruction manual didn't come with it."

In the preface for his "cosmic fairy tale" Tetrascroll: Goldilocks and the Three Bears, Fuller stated that his distinctive speaking style grew out of years of embellishing the classic tale for the benefit of his daughter, allowing him to explore both his new theories and how to present them. The Tetrascroll narrative was eventually transcribed onto a set of tetrahedral lithographs (hence the name), as well as being published as a traditional book.

Fuller's language posed problems for his credibility. John Julius Norwich recalled commissioning a 600-word introduction for a planned history of world architecture from him, and receiving a 3500-word proposal which ended:

We will see the (1) down-at-the-mouth-ends curvature of land civilisation's retrogression from the (2) straight raft line foundation of the Mayans' building foundation lines historically transformed to the (3) smiling, up-end curvature of maritime technology transformed through the climbing angle of wingfoil aeronautics progressing humanity into the verticality of outward-bound rocketry and inward-bound microcosmy, ergo (4) the ultimately invisible and vertically-lined architecture as humans master local environment with invisible electro-magnetic fields while travelling by radio as immortal pattern-integrities.

Norwich commented: "On reflection, I asked Dr. Nikolaus Pevsner instead."

His concepts and buildings include:

Buckminsterfullerene is a type of fullerene with the formula C₆₀. The names are homages to Buckminster Fuller, whose geodesic domes they resemble.

An allotrope of carbon, fullerene-and a particular molecule of that allotrope C ₆₀ ( buckminsterfullerene or buckyball) has been named after him. The Buckminsterfullerene molecule, which consists of 60 carbon atoms, very closely resembles a spherical version of Fuller's geodesic dome. The 1996 Nobel prize in chemistry was given to Kroto, Curl, and Smalley for their discovery of the fullerene.

On July 12, 2004, the United States Post Office released a new commemorative stamp honoring R. Buckminster Fuller on the 50th anniversary of his patent for the geodesic dome and by the occasion of his 109th birthday. The stamp's design replicated the January 10, 1964, cover of Time magazine.

Fuller was the subject of two documentary films: The World of Buckminster Fuller (1971) and Buckminster Fuller: Thinking Out Loud (1996). Additionally, filmmaker Sam Green and the band Yo La Tengo collaborated on a 2012 "live documentary" about Fuller, The Love Song of R. Buckminster Fuller.

In June 2008, the Whitney Museum of American Art presented "Buckminster Fuller: Starting with the Universe", the most comprehensive retrospective to date of his work and ideas. The exhibition traveled to the Museum of Contemporary Art, Chicago in 2009. It presented a combination of models, sketches, and other artifacts, representing six decades of the artist's integrated approach to housing, transportation, communication, and cartography. It also featured the extensive connections with Chicago from his years spent living, teaching, and working in the city.

In 2009, a number of US companies decided to repackage spherical magnets and sell them as toys. One company, Maxfield & Oberton, told The New York Times that they saw the product on YouTube and decided to repackage them as "Buckyballs", because the magnets could self-form and hold together in shapes reminiscent of the Fuller inspired buckyballs. The buckyball toy launched at New York International Gift Fair in 2009 and sold in the hundreds of thousands, but by 2010 began to experience problems with toy safety issues and the company was forced to recall the packages that were labelled as toys.

In 2012, the San Francisco Museum of Modern Art hosted "The Utopian Impulse" - a show about Buckminster Fuller's influence in the Bay Area. Featured were concepts, inventions and designs for creating "free energy" from natural forces, and for sequestering carbon from the atmosphere. The show ran January through July.

Fuller is quoted in "The Tower of Babble" from the musical : "Man is a complex of patterns and processes."

Belgian rock band dEUS released the song The Architect, inspired by Fuller, on their 2008 album Vantage Point.

Indie band Driftless Pony Club titled their 2011 album Buckminster after Fuller. Each of the album's songs is based upon his life and works.

The design podcast 99% Invisible (2010-present) takes its title from a Fuller quote: "Ninety-nine percent of who you are is invisible and untouchable."

Fuller is briefly mentioned in X-Men: Days of Future Past (2014) when Kitty Pryde is giving a lecture to a group of students regarding utopian architecture.

Robert Kiyosaki's 2015 book Second Chance concerns Kiyosaki's interactions with Fuller as well as Fuller's unusual final book, Grunch of Giants.

In The House of Tomorrow (2017), based on Peter Bognanni's 2010 novel of the same name, Ellen Burstyn's character is obsessed with Fuller and provides retro-futurist tours of her geodesic home that include videos of Fuller sailing and talking with Burstyn, who had in real life befriended Fuller.

(from the Table of Contents of Inventions: The Patented Works of R. Buckminster Fuller (1983) ISBN 0-312-43477-4)

1927 U.S. Patent 1,633,702 Stockade: building structure

1927 U.S. Patent 1,634,900 Stockade: pneumatic forming process

1928 (Application Abandoned) 4D house

1946 (No Patent) Dymaxion house (Wichita)

1963 U.S. Patent 3,080,583 Submarisle (undersea island)

1964 U.S. Patent 3,139,957 Aspension (suspension building)

1965 U.S. Patent 3,197,927 Monohex (geodesic structures)

1965 (Filed - No Patent) Octa spinner

1970 U.S. Patent 3,524,422 Rowing needles (watercraft)

1974 U.S. Patent 3,810,336 Geodesic hexa-pent

1975 U.S. Patent 3,866,366 Non-symmetrical tensegrity

1979 U.S. Patent 4,136,994 Floating breakwater

1980 U.S. Patent 4,207,715 Tensegrity truss

1983 U.S. Patent 4,377,114 Hanging storage shelf unit

Applewhite, E. J. (1977). Cosmic Fishing: An account of writing Synergetics with Buckminster Fuller. Macmillan. ISBN 978-0-02-502710-7.

Chu, Hsiao-Yun (Fall 2008). "Fuller's Laboratory Notebook". Collections. 4 (4): 295-306. doi:10.1177/155019060800400404. S2CID 189551410.

Hatch, Alden (1974). Buckminster Fuller At Home In The Universe. New York: Crown Publishers. ISBN 978-0-440-04408-6.

Hoogenboom, Olive (1999). "Fuller, R. Buckminster". American National Biography. Vol. 8 (online ed.). New York: Oxford University Press. pp. 559-562. doi:10.1093/anb/9780198606697.article.1302560. (subscription required)

Gorman, Michael John (2005). Buckminster Fuller: Designing for Mobility. Skira. ISBN 978-8876242656.

Kenner, Hugh (1973). Bucky: a guided tour of Buckminster Fuller. Morrow. ISBN 978-0-688-00141-4.

Krausse, Joachim; Lichtenstein, Claude, eds. (1999). Your Private Sky, R. Buckminster Fuller: The Art Of Design Science. Lars Mueller Publishers. ISBN 978-3-907044-88-9.

McHale, John (1962). R. Buckminster Fuller. New York: George Brazillier, Inc.

Pawley, Martin (1991). Buckminster Fuller. New York: Taplinger Publishing Company. ISBN 978-0-8008-1116-7.

Rovers, Eva (2019). De rebelse held. Amsterdam: Prometheus. ISBN 978-9-044-63882-0. Archived from the original on January 31, 2021.

Snyder, Robert (1980). Buckminster Fuller: An Autobiographical Monologue/Scenario. New York: St. Martin's Press. ISBN 978-0-312-24547-4.

Sterngold, James (June 15, 2008). "The Love Song of R. Buckminster Fuller". The New York Times (Arts section).

Ward, James, ed., The Artifacts Of R. Buckminster Fuller, A Comprehensive Collection of His Designs and Drawings in Four Volumes: Volume One. The Dymaxion Experiment, 1926-1943; Volume Two. Dymaxion Deployment, 1927-1946; Volume Three. The Geodesic Revolution, Part 1, 1947-1959; Volume Four. The Geodesic Revolution, Part 2, 1960-1983: Edited with descriptions by James Ward. Garland Publishing, New York. 1984 (ISBN 0-8240-5082-7 vol. 1, ISBN 0-8240-5083-5 vol. 2, ISBN 0-8240-5084-3 vol. 3, ISBN 0-8240-5085-1 vol. 4)

Wong, Yunn Chii (1999). The Geodesic Works of Richard Buckminster Fuller, 1948-1968 (The Universe as a Home of Man) (PhD thesis). Cambridge, Massachusetts: Massachusetts Institute of Technology, Department of Architecture. hdl:1721.1/9512.

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Richard Buckminster Fuller (; July 12, 1895 - July 1, 1983) was an American architect, systems theorist, writer, designer, inventor, philosopher, and futurist. He styled his name as R. Buckminster Fuller in his writings, publishing more than 30 books and coining or popularizing such terms as " Spaceship Earth", " Dymaxion" (e.g., Dymaxion house, Dymaxion car, Dymaxion map), " ephemeralization", " synergetics", and " tensegrity".

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Fullerene is another allotrope of carbon and is named after Buckminster Fuller. (Looks a bit like the panda mask in the "Up We Go" image.

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Fullerene is another allotrope of carbon and is named after Buckminster Fuller. (Looks a bit like the panda mask in the "Up We Go" image.

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A fullerene is an allotrope of carbon in the form of a hollow sphere, ellipsoid, tube, and many other shapes and sizes. Spherical fullerenes, also referred to as Buckminsterfullerenes or buckyballs, resemble the balls used in association football. Cylindrical fullerenes are also called carbon nanotubes (buckytubes).

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Possible CNS connection - Cloud Nine (sphere) is the name Buckminster Fuller gave to his proposed airborne habitats created from giant geodesic spheres

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Possible CNS connection - Cloud Nine (sphere) is the name Buckminster Fuller gave to his proposed airborne habitats created from giant geodesic spheres

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Cloud Nine is the name Buckminster Fuller gave to his proposed airborne habitats created from giant geodesic spheres, which might be made to levitate by slightly heating the air inside above the ambient temperature.[1]

Geodesic spheres (structures of triangular components arranged to make a sphere) become stronger as they become bigger, because of how they distribute stress over their surfaces. As a sphere gets bigger, the volume it encloses grows much faster than the mass of the enclosing structure itself. Fuller suggested that the mass of a mile-wide geodesic sphere would be negligible compared to the mass of the air trapped within it. He suggested that if the air inside such a sphere were heated even by one degree higher than the ambient temperature of its surroundings, the sphere could become airborne. He calculated that such a balloon could lift a considerable mass, and hence that 'mini-cities' or airborne towns of thousands of people could be built in this way.

A Cloud Nine could be tethered, or free-floating, or maneuverable so that it could migrate in response to climatic and environmental conditions, such as providing emergency shelters.[2]

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Cloud Nine is the name Buckminster Fuller gave to his proposed airborne habitats created from giant geodesic spheres, which might be made to levitate by slightly heating the air inside above the ambient temperature.[1] Geodesic spheres (structures of triangular components arranged to make a sphere) become stronger as they become bigger, because of how they distribute stress over their surfaces.

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Berzelius enrolled as a medical student at Uppsala University, from 1796 to 1801. Anders Gustaf Ekeberg, the discoverer of tantalum, taught him chemistry during this time

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Berzelius enrolled as a medical student at Uppsala University, from 1796 to 1801. Anders Gustaf Ekeberg, the discoverer of tantalum, taught him chemistry during this time

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Baron Jöns Jacob Berzelius ( Swedish: [jœns ˈjɑ̌ːkɔb bæˈʂěːlɪɵs]; by himself and his contemporaries named only Jacob Berzelius, 20 August 1779 - 7 August 1848) was a Swedish chemist. Berzelius is considered, along with Robert Boyle, John Dalton, and Antoine Lavoisier, to be one of the founders of modern chemistry. Berzelius became a member of the Royal Swedish Academy of Sciences in 1808 and served from 1818 as its principal functionary. He is known in Sweden as the "Father of Swedish Chemistry". Berzelius Day is celebrated on 20 August in honour of him.

Although Berzelius began his career as a physician, his enduring contributions were in the fields of electrochemistry, chemical bonding and stoichiometry. In particular, he is noted for his determination of atomic weights and his experiments that led to a more complete understanding of the principles of stoichiometry, which is the branch of chemistry pertaining to the quantitative relationships between elements in chemical compounds and chemical reactions and that these occur in definite proportions. This understanding came to be known as the "Law of Constant Proportions".

Berzelius was a strict empiricist, expecting that any new theory must be consistent with the sum of contemporary chemical knowledge. He developed improved methods of chemical analysis, which were required to develop the basic data in support of his work on stoichiometry. He investigated isomerism, allotropy, and catalysis, phenomena that owe their names to him. Berzelius was among the first to articulate the differences between inorganic compounds and organic compounds. Among the many minerals and elements he studied, he is credited with discovering cerium and selenium, and with being the first to isolate silicon and thorium. Following on his interest in mineralogy, Berzelius synthesized and chemically characterized new compounds of these and other elements.

Berzelius demonstrated the use of an electrochemical cell to decompose certain chemical compounds into pairs of electrically opposite constituents. From this research, he articulated a theory that came to be known as electrochemical dualism, contending that chemical compounds are oxide salts, bonded together by electrostatic interactions. This theory, while useful in some contexts, came to be seen as insufficient. Berzelius's work with atomic weights and his theory of electrochemical dualism led to his development of a modern system of chemical formula notation that showed the composition of any compound both qualitatively and quantitatively. His system abbreviated the Latin names of the elements with one or two letters and applied superscripts to designate the number of atoms of each element present in the compound. Later, chemists changed to use of subscripts rather than superscripts.

Berzelius was born in the parish of Väversunda in Östergötland in Sweden. His father Samuel Berzelius was a school teacher in the nearby city of Linköping, and his mother Elizabeth Dorothea Sjösteen was a homemaker. His parents were both from families of church pastors. Berzelius lost both his parents at an early age. His father died in 1779, after which his mother married a pastor named Anders Eckmarck, who gave Berzelius a basic education including knowledge of the natural world. Following the death of his mother in 1787, relatives in Linköping took care of him. There he attended the school today known as Katedralskolan. As a teenager, he took a position as a tutor at a farm near his home, during which time he became interested in collecting flowers and insects and their classification.

Berzelius later enrolled as a medical student at Uppsala University, from 1796 to 1801. Anders Gustaf Ekeberg, the discoverer of tantalum, taught him chemistry during this time. He worked as an apprentice in a pharmacy, during which time he also learned practical matters in the laboratory such as glassblowing. On his own during his studies, he successfully repeated the experimentation conducted by Swedish chemist Carl William Scheele which led to Scheele's discovery of oxygen. He also worked with a physician in the Medevi mineral springs. During this time, he conducted an analysis of the water from this source. Additionally as part of his studies, in 1800, Berzelius learned about Alessandro Volta's electric pile, the first device that could provide a constant electric current (i.e., the first battery). He constructed a similar battery for himself, consisting of alternating disks of copper and zinc, and this was his initial work in the field of electrochemistry.

As thesis research in his medical studies, he examined the influence of galvanic current on several diseases. This line of experimentation produced no clear-cut evidence for such influence. Berzelius graduated as a medical doctor in 1802. He worked as a physician near Stockholm until the chemist and mine-owner Wilhelm Hisinger recognized his abilities as an analytical chemist and provided him with a laboratory.

In 1807, Berzelius was appointed professor in chemistry and pharmacy at the Karolinska Institute. Between 1808 and 1836, Berzelius worked together with Anna Sundström, who acted as his assistant and was the first female chemist in Sweden.

In 1808, he was elected a member of the Royal Swedish Academy of Sciences. At this time, the Academy had been stagnating for several years, since the era of romanticism in Sweden had led to less interest in the sciences. In 1818, Berzelius was elected the Academy's secretary and held the post until 1848. During Berzelius' tenure, he is credited with revitalising the Academy and bringing it into a second golden era (the first being the astronomer Pehr Wilhelm Wargentin's period as secretary from 1749 to 1783). He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1822. In 1827, he became correspondent of the Royal Institute of the Netherlands, and in 1830 associate member. In 1837, he was elected a member of the Swedish Academy, on chair number 5.

Berzelius was active in the temperance movement. Along with Bengt Franc-Sparre, August von Hartmansdorff, Anders Retzius, Samuel Owen, George Scott, and others, he was one of the founders of the Svenska nykterhetssällskapet (the Swedish Temperance Society) in 1837 and its first chairman. Berzelius wrote the foreword to one of Carl af Ekenstam's works on the topic, of which 50,000 copies were printed.

Through much of his life, Berzelius suffered various medical ailments. These included recurrent migraine headaches and then later on he suffered from gout. He also had episodes of depression.

In 1818, Berzelius had a nervous breakdown, said to be due to the stress of his work. The medical advice he received was to travel and take vacation. However, during this time, Berzelius traveled to France to work in the chemical laboratories of Claude Louis Berthollet.

In 1835, at the age of 56, he married Elizabeth Poppius, the 24-year-old daughter of a Swedish cabinet minister.

He died on 7 August 1848 at his home in Stockholm, where he had lived since 1806. He is buried in the Solna Cemetery.

Soon after arriving in Stockholm, Berzelius wrote a chemistry textbook for his medical students, Lärbok i Kemien, which was his first significant scientific publication. He had conducted experimentation, in preparation for writing this textbook, on the compositions of inorganic compounds, which was his earliest work on definite proportions. In 1813, he published an essay on the proportions of elements in compounds. The essay commenced with a general description, introduced his new symbolism, examined all the known elements, included a table of specific weights, and finished with a selection of compounds written in his new formalism. In 1818, he compiled a table of relative atomic weights, where oxygen was set to 100, and which included all of the elements known at the time. This work provided evidence in favour of the atomic theory proposed by John Dalton: that inorganic chemical compounds are composed of atoms of different elements combined in whole number amounts. In discovering that atomic weights are not integer multiples of the weight of hydrogen, Berzelius also disproved Prout's hypothesis that elements are built up from atoms of hydrogen. Berzelius's last revised version of his atomic weight tables was first published in a German translation of his Textbook of Chemistry in 1826.

In order to aid his experiments, he developed a system of chemical notation in which the elements composing any particular chemical compound were given simple written labels-such as O for oxygen, or Fe for iron-with their proportions in the chemical compound denoted by numbers. Berzelius thus invented the system of chemical notation still used today, the main difference being that instead of the subscript numbers used today (e.g., H ₂O or Fe ₂O ₃), Berzelius used superscripts (H ²O or Fe ²O ³).

Berzelius is credited with discovering the chemical elements cerium and selenium and with being the first to isolate silicon and thorium. Berzelius discovered cerium in 1803 and selenium in 1817. Berzelius also discovered how to isolate silicon in 1824, and thorium in 1824. Students working in Berzelius's laboratory also discovered lithium, lanthanum, and vanadium.

Berzelius discovered amorphous silicon by repeating an experiment performed by Gay-Lussac and Thénard in which they reacted silicon tetrafluoride with potassium metal which produced very impure silicon. In a variation of this experiment Berzelius heated potassium fluorosilicate with potassium. It produced potassium silicide which he then stirred with water to produce relatively pure silicon powder. Berzelius recognized this powder as the new element of silicon, which he called silicium, a name proposed earlier by Davy.

Berzelius was the first to isolate zirconium in 1824, but pure zirconium was not produced until 1925, by Anton Eduard van Arkel and Jan Hendrik de Boer.

Berzelius is credited with originating the chemical terms " catalysis", " polymer," " isomer," " protein" and " allotrope," although his original definitions in some cases differ significantly from modern usage. As an example, he coined the term "polymer" in 1833 to describe organic compounds which shared identical empirical formulas but which differed in overall molecular weight, the larger of the compounds being described as "polymers" of the smallest. At this time the concept of chemical structure had not yet been developed so that he considered only the numbers of atoms of each element. In this way, he viewed for example glucose (C ₆H ₁₂O ₆) as a polymer of formaldehyde (CH ₂O), even though we now know that glucose is not a polymer of the monomer formaldehyde.

Berzelius was the first person to make the distinction between organic compounds (those containing carbon), and inorganic compounds. In particular, he advised Gerardus Johannes Mulder in his elemental analyses of organic compounds such as coffee, tea, and various proteins. The term protein itself was coined by Berzelius, in 1838, after Mulder observed that all proteins seemed to have the same empirical formula and came to the erroneous conclusion that they might be composed of a single type of very large molecule. The term is derived from the Greek, meaning "of the first rank", and Berzelius proposed the name because proteins were so fundamental to living organisms.

In 1808, Berzelius discovered that lactic acid occurs in muscle tissue, not just in milk.

The term biliverdin was coined by Berzelius in 1840, although he preferred "bilifulvin" (yellow/red) over "bilirubin" (red).

Berzelius stated in 1810 that living things work by some mysterious "vital force", a hypothesis called vitalism. Vitalism had first been proposed by prior researchers, although Berzelius contended that compounds could be distinguished by whether they required any organisms in their synthesis ( organic compounds) or whether they did not ( inorganic compounds). However, in 1828, Friedrich Wöhler accidentally obtained urea, an organic compound, by heating ammonium cyanate. This showed that an organic compound such as urea could be prepared synthetically and not exclusively by living organisms. Berzelius corresponded with Wöhler on the urea synthesis findings. However, the notion of vitalism continued to persist, until further work on abiotic synthesis of organic compounds provided substantial evidence against vitalism.

Berzelius was a prolific correspondent with leading scientists of his time, such as Gerardus Johannes Mulder, Claude Louis Berthollet, Humphry Davy, Friedrich Wöhler, Eilhard Mitscherlich and Christian Friedrich Schönbein.

In 1812, Berzelius traveled to London, England, including Greenwich to meet with prominent British scientists of the time. These included Humphry Davy, chemist William Wollaston, physician-scientist Thomas Young, astronomer William Herschel, chemist Smithson Tennant, and inventor James Watt, among others. Berzelius also visited Davy's laboratory. After his visit to Davy's laboratory, Berzelius remarked, "A tidy laboratory is a sign of a lazy chemist."

Humphry Davy in 1810 proposed that chlorine is an element. Berzelius rejected this claim because of his belief that all acids were based on oxygen, and HCl contains no oxygen and so could not be an element, in Berzelius's perception. However, in 1812, Bernard Courtois proved that the isoelectronic substance iodine is an element. This finding resolved Berzelius's disagreement. Berzelius continued his investigations into the chemistry of chlorine during his stay in Claude Louis Berthollet's laboratory.

In 1818 Berzelius was ennobled by King Carl XIV Johan. In 1835, he received the title of friherre.

In 1820 he was elected a member of the American Philosophical Society.

The Royal Society of London gave Berzelius the Copley Medal in 1836 with the citation "For his systematic application of the doctrine of definite proportions to the analysis of mineral bodies, as contained in his Nouveau Systeme de Mineralogie, and in other of his works."[citation needed ]

In 1840, Berzelius was named Knight of the Order of Leopold. In 1842, he received the honor Pour le Mérite for Sciences and Arts.

The mineral berzelianite, a copper selenide, was discovered in 1850 and named after him by James Dwight Dana.

In 1852, Stockholm, Sweden, built a public park and statue, both to honor Berzelius. Berzeliusskolan, a school situated next to his alma mater, Katedralskolan, is named for him. In 1890, a fairly prominent street in Gothenburg was named Berzeliigatan (Berzelii street) in his honour.

In 1898, the Swedish Academy of Sciences opened the Berzelius Museum in honor of Berzelius. The holdings of the museum included many items from his laboratory. The museum was opened on the occasion of fiftieth anniversary of Berzelius's death. Invitees at the ceremony marking the occasion included scientific dignitaries from eleven European nations and the United States, many of whom gave formal addresses in honor of Berzelius. The Berzelius Museum was later moved to the observatory that is part of the Swedish Academy of Sciences.

In 1939 his portrait appeared on a series of postage stamps commemorating the bicentenary of the founding of the Swedish Academy of Sciences. In addition to Sweden, Grenada likewise honored him.

The Berzelius secret society at Yale University is named in his honor.

Jaime Wisniak (2000). "Jöns Jacob Berzelius A Guide to the Perplexed Chemist". The Chemical Educator. 5 (6): 343-350. doi:10.1007/s00897000430a. S2CID 98774420.

Paul Walden (1947). "Zum 100. Todestag von Jöns Jakob Berzelius am 7. August 1948". Naturwissenschaften. 34 (11): 321-327. Bibcode:1947NW.....34..321W. doi:10.1007/BF00644137. S2CID 36477981.

Holmberg, Arne (1933) Bibliografi över J. J. Berzelius. 2 parts in 5 vol. Stockholm: Kungl. Svenska Vetenskapsakademien, 1933-67. 1. del och suppl. 1-2. Tryckta arbeten av och om Berzelius. 2. del och suppl. Manuskript

Jorpes, J. Erik (1966) Jac. Berzelius - his life and work; translated from the Swedish manuscript by Barbara Steele. Stockholm: Almqvist & Wiksell, 1966. (Reissued by University of California Press, Berkeley, 1970 ISBN 0-520-01628-9)

Leicester, Henry (1970-1980). "Berzelius, Jöns Jacob". Dictionary of Scientific Biography. Vol. 2. New York: Charles Scribner's Sons. pp. 90-97. ISBN 978-0-684-10114-9.

Partington, J. R. (1964) History of Chemistry; vol. 4. London: Macmillan; pp. 142-77

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Baron Jöns Jacob Berzelius ( Swedish: [jœns ˈjɑ̌ːkɔb bæˈʂěːlɪɵs]; by himself and his contemporaries named only Jacob Berzelius, 20 August 1779 - 7 August 1848) was a Swedish chemist. Berzelius is considered, along with Robert Boyle, John Dalton, and Antoine Lavoisier, to be one of the founders of modern chemistry.

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The concept of allotropy was originally proposed in 1840 by the Swedish scientist Baron Jöns Jakob Berzelius (1779–1848).

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The concept of allotropy was originally proposed in 1840 by the Swedish scientist Baron Jöns Jakob Berzelius (1779–1848).

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Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other', and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications of an element; the atoms of the element are bonded together in a different manner. For example, the allotropes of carbon include diamond (the carbon atoms are bonded together in a tetrahedral lattice arrangement), graphite (the carbon atoms are bonded together in sheets of a hexagonal lattice), graphene (single sheets of graphite), and fullerenes (the carbon atoms are bonded together in spherical, tubular, or ellipsoidal formations).

The term allotropy is used for elements only, not for compounds. The more general term, used for any crystalline material, is polymorphism. Allotropy refers only to different forms of an element within the same phase (i.e.: solid, liquid or gas states); the differences between these states would not alone constitute examples of allotropy.

For some elements, allotropes have different molecular formulae despite difference in phase; for example, two allotropes of oxygen ( dioxygen, O ₂, and ozone, O ₃) can both exist in the solid, liquid and gaseous states. Other elements do not maintain distinct allotropes in different phases; for example, phosphorus has numerous solid allotropes, which all revert to the same P ₄ form when melted to the liquid state.

The concept of allotropy was originally proposed in 1841 by the Swedish scientist Baron Jöns Jakob Berzelius (1779-1848). The term is derived from Greek άλλοτροπἱα (allotropia) 'variability, changeableness'. After the acceptance of Avogadro's hypothesis in 1860, it was understood that elements could exist as polyatomic molecules, and two allotropes of oxygen were recognized as O ₂ and O ₃. In the early 20th century, it was recognized that other cases such as carbon were due to differences in crystal structure.

By 1912, Ostwald noted that the allotropy of elements is just a special case of the phenomenon of polymorphism known for compounds, and proposed that the terms allotrope and allotropy be abandoned and replaced by polymorph and polymorphism. Although many other chemists have repeated this advice, IUPAC and most chemistry texts still favour the usage of allotrope and allotropy for elements only.

Differences in properties of an element's allotropes

Allotropes are different structural forms of the same element and can exhibit quite different physical properties and chemical behaviours. The change between allotropic forms is triggered by the same forces that affect other structures, i.e., pressure, light, and temperature. Therefore, the stability of the particular allotropes depends on particular conditions. For instance, iron changes from a body-centered cubic structure ( ferrite) to a face-centered cubic structure ( austenite) above 906 °C, and tin undergoes a modification known as tin pest from a metallic form to a semiconductor form below 13.2 °C (55.8 °F). As an example of allotropes having different chemical behaviour, ozone (O ₃) is a much stronger oxidizing agent than dioxygen (O ₂).

Typically, elements capable of variable coordination number and/or oxidation states tend to exhibit greater numbers of allotropic forms. Another contributing factor is the ability of an element to catenate.

Examples of allotropes include:

Diamond - an extremely hard, transparent crystal, with the carbon atoms arranged in a tetrahedral lattice. A poor electrical conductor. An excellent thermal conductor.

Lonsdaleite - also called hexagonal diamond.

Graphene - is the basic structural element of other allotropes, nanotubes, charcoal, and fullerenes.

Q-carbon - a ferromagnetic, tough, and brilliant crystal structure that is harder and brighter than diamonds.[dubious ]

Graphite - a soft, black, flaky solid, a moderate electrical conductor. The C atoms are bonded in flat hexagonal lattices (graphene), which are then layered in sheets.

Linear acetylenic carbon (Carbyne)

Amorphous carbon

Fullerenes, including Buckminsterfullerene, a.k.a. "buckyballs", such as C₆₀.

Carbon nanotubes - allotropes of carbon with a cylindrical nanostructure.

Schwarzites

Cyclocarbon

Glassy carbon

"Red selenium," cyclo-Se₈

Gray selenium, polymeric Se

Black selenium, irregular polymeric rings up to 1000 atoms long

Monoclinic selenium, dark red transparent crystals

Amorphous boron - brown powder - B₁₂ regular icosahedra

α-rhombohedral boron

β-rhombohedral boron

γ-orthorhombic boron

α-tetragonal boron

β-tetragonal boron

High-pressure superconducting phase

Yellow arsenic - molecular non-metallic As₄, with the same structure as white phopshorus

Gray arsenic, polymeric As (metalloid)

Black arsenic - molecular and non-metallic, with the same structure as red phosphorus

α-germanium - semimetallic, with the same structure as diamond

β-germanium - metallic, with the same structure as beta-tin

Germanene - Buckled planar Germanium, similar to graphene

blue-white antimony - stable form (metalloid), with the same structure as gray arsenic

yellow antimony (non-metallic)

black antimony (non-metallic)

explosive antimony

amorphous tellurium - gray-black or brown powder

crystalline tellurium - hexagonal crystalline structure (metalloid)

Among the metallic elements that occur in nature in significant quantities (56 up to U, without Tc and Pm), almost half (27) are allotropic at ambient pressure: Li, Be, Na, Ca, Ti, Mn, Fe, Co, Sr, Y, Zr, Sn, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Yb, Hf, Tl, Th, Pa and U. Some phase transitions between allotropic forms of technologically relevant metals are those of Ti at 882 °C, Fe at 912 °C and 1394 °C, Co at 422 °C, Zr at 863 °C, Sn at 13 °C and U at 668 °C and 776 °C.

Lanthanides and actinides

Cerium, samarium, dysprosium and ytterbium have three allotropes.

Praseodymium, neodymium, gadolinium and terbium have two allotropes.

Plutonium has six distinct solid allotropes under "normal" pressures. Their densities vary within a ratio of some 4:3, which vastly complicates all kinds of work with the metal (particularly casting, machining, and storage). A seventh plutonium allotrope exists at very high pressures. The transuranium metals Np, Am, and Cm are also allotropic.

Promethium, americium, berkelium and californium have three allotropes each.

In 2017, the concept of nanoallotropy was proposed by Prof. Rafal Klajn of the Organic Chemistry Department of the Weizmann Institute of Science. Nanoallotropes, or allotropes of nanomaterials, are nanoporous materials that have the same chemical composition (e.g., Au), but differ in their architecture at the nanoscale (that is, on a scale 10 to 100 times the dimensions of individual atoms). Such nanoallotropes may help create ultra-small electronic devices and find other industrial applications. The different nanoscale architectures translate into different properties, as was demonstrated for surface-enhanced Raman scattering performed on several different nanoallotropes of gold. A two-step method for generating nanoallotropes was also created.

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Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other', and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications of an element; the atoms of the element are bonded together in a different manner.

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Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite. In recent decades, many more allotropes have been discovered and researched including ball shapes such as buckminsterfullerene and sheets such as graphene. Larger scale structures of carbon include nanotubes, nanobuds and nanoribbons. Other unusual forms of carbon exist at very high temperatures or extreme pressures. Around 500 hypothetical 3-periodic allotropes of carbon are known at the present time, according to the Samara Carbon Allotrope Database (SACADA).

Diamond is a well known allotrope of carbon. The hardness and high dispersion of light of diamond make it useful for both industrial applications and jewelry. Diamond is the hardest known natural mineral. This makes it an excellent abrasive and makes it hold polish and luster extremely well. No known naturally occurring substance can cut (or even scratch) a diamond, except another diamond.

The market for industrial-grade diamonds operates much differently from its gem-grade counterpart. Industrial diamonds are valued mostly for their hardness and heat conductivity, making many of the gemological characteristics of diamond, including clarity and color, mostly irrelevant. This helps explain why 80% of mined diamonds (equal to about 100 million carats or 20 tonnes annually) are unsuitable for use as gemstones and known as , are destined for industrial use. In addition to mined diamonds, synthetic diamonds found industrial applications almost immediately after their invention in the 1950s; another 400 million carats (80 tonnes) of synthetic diamonds are produced annually for industrial use, which is nearly four times the mass of natural diamonds mined over the same period.

Each carbon atom in a diamond is covalently bonded to four other carbons in a tetrahedron. These tetrahedrons together form a 3-dimensional network of six-membered carbon rings (similar to cyclohexane), in the chair conformation, allowing for zero bond angle strain. This stable network of covalent bonds and hexagonal rings is the reason that diamond is so strong. Although graphite is the most stable allotrope of carbon under standard laboratory conditions (273 or 298 K, 1 atm), a recent computational study indicated that under idealized conditions ( T = 0, p = 0), diamond is the most stable allotrope by 1.1 kJ/mol compared to graphite.

Graphite, named by Abraham Gottlob Werner in 1789, from the Greek γράφειν ( graphein, "to draw/write", for its use in pencils) is one of the most common allotropes of carbon. Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes. Likewise, under standard conditions, graphite is the most stable form of carbon. Therefore, it is used in thermochemistry as the standard state for defining the heat of formation of carbon compounds.

Graphite conducts electricity, due to delocalization of the pi bond electrons above and below the planes of the carbon atoms. These electrons are free to move, so are able to conduct electricity. However, the electricity is only conducted along the plane of the layers. In diamond, all four outer electrons of each carbon atom are 'localized' between the atoms in covalent bonding. The movement of electrons is restricted and diamond does not conduct an electric current. In graphite, each carbon atom uses only 3 of its 4 outer energy level electrons in covalently bonding to three other carbon atoms in a plane. Each carbon atom contributes one electron to a delocalized system of electrons that is also a part of the chemical bonding. The delocalized electrons are free to move throughout the plane. For this reason, graphite conducts electricity along the planes of carbon atoms, but does not conduct in a direction at right angles to the plane.

When a large number of crystallographic defects (physical) bind these planes together, graphite loses its lubrication properties and becomes pyrolytic carbon, a useful material in blood-contacting implants such as prosthetic heart valves.

Graphite is the most stable allotrope of carbon. Contrary to popular belief, high-purity graphite does not readily burn, even at elevated temperatures. For this reason, it is used in nuclear reactors and for high-temperature crucibles for melting metals. At very high temperatures and pressures (roughly 2000 °C and 5 GPa), it can be transformed into diamond.[citation needed ]

Natural and crystalline graphites are not often used in pure form as structural materials due to their shear-planes, brittleness and inconsistent mechanical properties.

Intumescent or expandable graphites are used in fire seals, fitted around the perimeter of a fire door. During a fire the graphite intumesces (expands and chars) to resist fire penetration and prevent the spread of fumes. A typical start expansion temperature (SET) is between 150 and 300 °C.

Density: graphite's specific gravity is 2.3, which makes it lighter than diamonds.

Chemical activity: it is slightly more reactive than diamond. This is because the reactants are able to penetrate between the hexagonal layers of carbon atoms in graphite. It is unaffected by ordinary solvents, dilute acids, or fused alkalis. However, chromic acid oxidizes it to carbon dioxide.

A single layer of graphite is called graphene and has extraordinary electrical, thermal, and physical properties. It can be produced by epitaxy on an insulating or conducting substrate or by mechanical exfoliation (repeated peeling) from graphite. Its applications may include replacing silicon in high-performance electronic devices. With two layers stacked, bilayer graphene results with different properties.

Graphenylene is a single layer carbon material with biphenylene-like subunits as basis in its hexagonal lattice structure. It is also known as biphenylene-carbon.

AA'-graphite

AA'-graphite is an allotrope of carbon similar to graphite, but where the layers are positioned differently to each other as compared to the order in graphite.

Diamane is a 2D form of diamond. It can be made via high pressures, but without that pressure, the material reverts to graphene. Another technique is to add hydrogen atoms but those bonds are weak. Using flourine (xenon-diflouride) instead brings the layers closer together, strengthening the bonds. This is called f-diamane.

Amorphous carbon is the name used for carbon that does not have any crystalline structure. As with all glassy materials, some short-range order can be observed, but there is no long-range pattern of atomic positions. While entirely amorphous carbon can be produced, most amorphous carbon actually contains microscopic crystals of graphite-like, or even diamond-like carbon.

Coal and soot or carbon black are informally called amorphous carbon. However, they are products of pyrolysis (the process of decomposing a substance by the action of heat), which does not produce true amorphous carbon under normal conditions.

The buckminsterfullerenes, or usually just fullerenes or buckyballs for short, were discovered in 1985 by a team of scientists from Rice University and the University of Sussex, three of whom were awarded the 1996 Nobel Prize in Chemistry. They are named for the resemblance to the geodesic structures devised by Richard Buckminster "Bucky" Fuller. Fullerenes are positively curved molecules of varying sizes composed entirely of carbon, which take the form of a hollow sphere, ellipsoid, or tube.

As of the early twenty-first century, the chemical and physical properties of fullerenes are still under heavy study, in both pure and applied research labs. In April 2003, fullerenes were under study for potential medicinal use - binding specific antibiotics to the structure to target resistant bacteria and even target certain cancer cells such as melanoma.

Carbon nanotubes, also called buckytubes, are cylindrical carbon molecules with novel properties that make them potentially useful in a wide variety of applications (e.g., nano-electronics, optics, materials applications, etc.). They exhibit extraordinary strength, unique electrical properties, and are efficient conductors of heat. Inorganic nanotubes have also been synthesized. A nanotube is a member of the fullerene structural family, which also includes buckyballs. Whereas buckyballs are spherical in shape, a nanotube is cylindrical, with at least one end typically capped with a hemisphere of the buckyball structure. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the width of a human hair), while they can be up to several centimeters in length. There are two main types of nanotubes: single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs).

Carbon nanobuds are a newly discovered allotrope of carbon in which fullerene like "buds" are covalently attached to the outer sidewalls of the carbon nanotubes. This hybrid material has useful properties of both fullerenes and carbon nanotubes. For instance, they have been found to be exceptionally good field emitters.

Schwarzites are negatively curved carbon surfaces originally proposed by decorating triply periodic minimal surfaces with carbon atoms. The geometric topology of the structure is determined by the presence of ring defects, such as heptagons and octagons, to graphene's hexagonal lattice. (Negative curvature bends surfaces outwards like a saddle rather than bending inwards like a sphere.)

Recent work has proposed Zeolite-templated carbons (ZTCs) may be Schwarzites. The name, ZTC, derives from their origin inside the pores of zeolites, crystalline silicon dioxide minerals. A vapor of carbon-containing molecules is injected into the zeolite, where the carbon gathers on the pores' walls, creating the negative curve. Dissolving the zeolite leaves the carbon. A team generated structures by decorating the pores of a zeolite with carbon through a Monte Carlo method. Some of these structures were recognized as Schwarzites and they proposed a route to their synthesis.

Glassy carbon or vitreous carbon is a class of non-graphitizing carbon widely used as an electrode material in electrochemistry, as well as for high-temperature crucibles and as a component of some prosthetic devices.

It was first produced by Bernard Redfern in the mid-1950s at the laboratories of The Carborundum Company, Manchester, UK. He had set out to develop a polymer matrix to mirror a diamond structure and discovered a resole (phenolic) resin that would, with special preparation, set without a catalyst. Using this resin the first glassy carbon was produced.

The preparation of glassy carbon involves subjecting the organic precursors to a series of heat treatments at temperatures up to 3000 °C. Unlike many non-graphitizing carbons, they are impermeable to gases and are chemically extremely inert, especially those prepared at very high temperatures. It has been demonstrated that the rates of oxidation of certain glassy carbons in oxygen, carbon dioxide or water vapor are lower than those of any other carbon. They are also highly resistant to attack by acids. Thus, while normal graphite is reduced to a powder by a mixture of concentrated sulfuric and nitric acids at room temperature, glassy carbon is unaffected by such treatment, even after several months.

Under certain conditions, carbon can be found in its atomic form. It is formed by passing large electric currents through carbon under very low pressures. It is extremely unstable, but it is an intermittent product used in the creation of carbenes.

Diatomic carbon can also be found under certain conditions. It is often detected via spectroscopy in extraterrestrial bodies, including comets and certain stars.

Carbon nanofoam is the fifth known allotrope of carbon, discovered in 1997 by Andrei V. Rode and co-workers at the Australian National University in Canberra. It consists of a low-density cluster-assembly of carbon atoms strung together in a loose three-dimensional web.

Each cluster is about 6 nanometers wide and consists of about 4000 carbon atoms linked in graphite-like sheets that are given negative curvature by the inclusion of heptagons among the regular hexagonal pattern. This is the opposite of what happens in the case of buckminsterfullerenes, in which carbon sheets are given positive curvature by the inclusion of pentagons.

The large-scale structure of carbon nanofoam is similar to that of an aerogel, but with 1% of the density of previously produced carbon aerogels - only a few times the density of air at sea level. Unlike carbon aerogels, carbon nanofoam is a poor electrical conductor.

Carbide-derived carbon (CDC) is a family of carbon materials with different surface geometries and carbon ordering that are produced via selective removal of metals from metal carbide precursors, such as TiC, SiC, Ti ₃AlC ₂, Mo ₂ C, etc. This synthesis is accomplished using chlorine treatment, hydrothermal synthesis, or high-temperature selective metal desorption under vacuum. Depending on the synthesis method, carbide precursor, and reaction parameters, multiple carbon allotropes can be achieved, including endohedral particles composed of predominantly amorphous carbon, carbon nanotubes, epitaxial graphene, nanocrystalline diamond, onion-like carbon, and graphitic ribbons, barrels, and horns. These structures exhibit high porosity and specific surface areas, with highly tunable pore diameters, making them promising materials for supercapacitor-based energy storage, water filtration and capacitive desalinization, catalyst support, and cytokine removal.

Lonsdaleite (hexagonal diamond)

Lonsdaleite is a hexagonal allotrope of the carbon allotrope diamond, believed to form from graphite present in meteorites upon their impact to Earth. The great heat and stress of the impact transforms the graphite into diamond, but retains graphite's hexagonal crystal lattice. Hexagonal diamond has also been synthesized in the laboratory, by compressing and heating graphite either in a static press or using explosives. It can also be produced by the thermal decomposition of a polymer, poly(hydridocarbyne), at atmospheric pressure, under inert gas atmosphere (e.g. argon, nitrogen), starting at temperature 110 °C (230 °F).

A one-dimensional carbon polymer with the structure -(C:::C) n -.

D-carbon: D-carbon was proposed by theorists in 2018. D-carbon is an orthorhombic sp³ carbon allotrope (6 atoms per cell). Total-energy calculations demonstrate that D-carbon is energetically more favorable than the previously proposed T₆ structure (with 6 atoms per cell) as well as many others.

is a mineral believed to have been formed in meteorite impacts. It has been described as slightly harder than graphite with a reflection color of grey to white. However, the existence of carbyne phases is disputed - see the entry on chaoite for details.

Metallic carbon: Theoretical studies have shown that there are regions in the phase diagram, at extremely high pressures, where carbon has metallic character.

bcc-carbon: At ultrahigh pressures of above 1000 GPa, diamond is predicted to transform into the so-called C₈ structure, a body-centered cubic structure with 8 atoms in the unit cell. This cubic carbon phase might have importance in astrophysics. Its structure is known in one of the metastable phases of silicon and is similar to cubane. Superdense and superhard material resembling this phase has been synthesized and published in 1979 and 2008. The structure of this phase was proposed in 2012 as carbon sodalite.

bct-carbon: Body-centered tetragonal carbon proposed by theorists in 2010

M-carbon: Monoclinic C-centered carbon was first thought to have been created in 1963 by compressing graphite at room temperature. Its structure was theorized in 2006, then in 2009 it was related to those experimental observations. Many structural candidates, including bct-carbon, were proposed to be equally compatible with experimental data available at the time, until in 2012 it was theoretically proven that this structure is kinetically likeliest to form from graphite. High-resolution data appeared shortly after, demonstrating that among all structure candidates only M-carbon is compatible with experiment.

T-carbon: Every carbon atom in diamond is replaced with a carbon tetrahedron (hence 'T-carbon'). This was proposed by theorists in 1985.

There is evidence that white dwarf stars have a core of crystallized carbon and oxygen nuclei. The largest of these found in the universe so far, BPM 37093, is located 50 light-years (4.7×10¹⁴ km) away in the constellation Centaurus. A news release from the Harvard-Smithsonian Center for Astrophysics described the 2,500-mile (4,000 km)-wide stellar core as a diamond, and it was named as Lucy, after the Beatles' song "Lucy in the Sky With Diamonds"; however, it is more likely an exotic form of carbon.

The Laves graph or is a theoretically-predicted three-dimensional crystalline metastable carbon structure in which each carbon atom is bonded to three others, at 120° angles (like graphite), but where the bond planes of adjacent layers lie at an angle of 70.5°, rather than coinciding

Penta-graphene

Haeckelites Ordered arrangements of pentagons, hexagons, and heptagons which can either be flat or tubular.

Phagraphene Graphene allotrope with distorted Dirac cones.

A combination of both hexagonal diamond and sp² hexagons as in graphene.

A hexagonal crystal structure with a fully relaxed primitive cell involving 48 atoms. Of these, 12 atoms have the potential to switch hybridization between sp² and sp³, forming dimers.

A combination of linear sp carbon chains and sp3 bulk carbon. The structure of these crystalline carbon allotropes consists of sp chains inserted in cylindrical cavities periodically arranged in hexagonal diamond (lonsdaleite).

U carbon is predicted to consist of corrugated layers tiled with six- or 12-atom rings, linked by covalent bonds. Notably, it is harder than steel, as conductive as stainless steel, highly reflective and ferromagnetic, behaving as a permanent magnet at temperatures up to 125 °C.

The system of carbon allotropes spans an astounding range of extremes, considering that they are all merely structural formations of the same element.

Between diamond and graphite:

Diamond crystallizes in the cubic system but graphite crystallizes in the hexagonal system.

Diamond is clear and transparent, but graphite is black and opaque.

Diamond is the hardest mineral known (10 on the Mohs scale), but graphite is one of the softest (1-2 on Mohs scale).

Diamond is the ultimate abrasive, but graphite is soft and is a very good lubricant.

Diamond is an excellent electrical insulator, but graphite is an excellent conductor.

Diamond is an excellent thermal conductor, but some forms of graphite are used for thermal insulation (for example heat shields and firebreaks).

At standard temperature and pressure, graphite is the thermodynamically stable form. Thus diamonds do not exist forever. The conversion from diamond to graphite, however, has a very high activation energy and is therefore extremely slow.

Despite the hardness of diamonds, the chemical bonds that hold the carbon atoms in diamonds together are actually weaker than those that hold together graphite. The difference is that in diamond, the bonds form an inflexible three-dimensional lattice. In graphite, the atoms are tightly bonded into sheets, but the sheets can slide easily over each other, making graphite soft.

1. ^ Hoffmann, R.; Kabanov, A.; Golov, A.; Proserpio, D. (2016). "Homo Citans and Carbon Allotropes: For an Ethics of Citation". Angewandte Chemie. 55 (37): 10962-10976. doi:10.1002/anie.201600655. PMC . PMID 27438532.

2. ^ Irving, Michael (2019-12-10). "Ultrathin diamond film made from graphene could toughen up electronics". New Atlas.

3. ^ Randall L. Vander Wal (1996). "Soot Precursor Material: Spatial Location via Simultaneous LIF-LII Imaging and Characterization via TEM" (PDF). Twenty-sixth Symposium (International) on Combustion. The Combustion Institute. pp. 2269-2275.

4. ^ McNaught, A. D.; Wilkinson, A., eds. (1997). "diamond-like carbon films". IUPAC Compendium of Chemical Terminology 2nd Edition. Oxford: Blackwell Scientific Publications. doi:10.1351/goldbook.D01673. ISBN 978-0-9678550-9-7.

5. ^ Terrones, Humberto (February 15, 1993). "Triply periodic minimal surfaces decorated with curved graphite". Chemical Physics Letters. 207 (1): 45-50. Bibcode:1993CPL...207...45T. doi:10.1016/0009-2614(93)85009-D.

6. ^ Irving, Michael (August 13, 2018). "Negative curvature schwarzite rounds out trinity of carbon nanostructures". newatlas.com.

7. ^ Bianconi P, et al. (2004). "Diamond and Diamond-like Carbon from a Preceramic Polymer". Journal of the American Chemical Society. 126 (10): 3191-3202. doi:10.1021/ja039254l. PMID 15012149.

8. ^ Nur, Yusuf; Cengiz, Halime M.; Pitcher, Michael W.; Toppare, Levent K. (2009). "Electrochemical polymerizatıon of hexachloroethane to form poly(hydridocarbyne): a pre-ceramic polymer for diamond production". Journal of Materials Science. 44 (11): 2774. Bibcode:2009JMatS..44.2774N. doi:10.1007/s10853-009-3364-4.

9. ^ Kaiser, K.; Scriven, L.M.; Schulz, F.; Gawel, P.; Gross, L.; Anderson, H.L. (2019). "An sp-hybridized molecular carbon allotrope, cyclo[18]carbon". Science. 365 (6455): 1299-1301. arXiv:. doi:10.1126/science.aay1914. PMID 31416933.

10. ^ Matyushenko N.N.; Strel'nitsky V.E. (1979). "JETP Letters: issues online". www.jetpletters.ac.ru. p. 199.

11. ^ Liu, P; Cao, Yl; Wang, Cx; Chen, Xy; Yang, Gw (Aug 2008). "Micro- and nanocubes of carbon with C8-like and blue luminescence". Nano Letters. 8 (8): 2570-5. Bibcode:2008NanoL...8.2570L. doi:10.1021/nl801392v. ISSN 1530-6984. PMID 18651780.

12. ^ Pokropivny, Alex; Volz, Sebastian (2012-09-01). "'C8 phase': Supercubane, tetrahedral, BC-8 or carbon sodalite?". Physica Status Solidi B. 249 (9): 1704-1708. Bibcode:2012PSSBR.249.1704P. doi:10.1002/pssb.201248185. ISSN 1521-3951.

13. ^ Oganov, Artem R. (27 June 2012). "Researchers establish structure of a new superhard form of carbon".

14. ^ Wang Y.; Panzik J.E.; Kiefer B.; Lee K.K.M. (2012). "Crystal structure of graphite under room-temperature compression and decompression". Scientific Reports. 2: 520. Bibcode:2012NatSR...2E.520W. doi:10.1038/srep00520. PMC . PMID 22816043.

15. ^ Lee, Kanani K. M. (20 July 2012). "Diamond in the rough: Half-century puzzle solved".

16. ^ Narayan, Jagdish; Bhaumik, Anagh (2 December 2015). "Novel phase of carbon, ferromagnetism, and conversion into diamond". Journal of Applied Physics. 118 (215303): 215303. Bibcode:2015JAP...118u5303N. doi:10.1063/1.4936595.

17. ^ "This Valentine's Day, Give The Woman Who Has Everything The Galaxy's Largest Diamond". Center for Astrophysics.

18. ^ Burchfield, Larry A; Fahim, Mohamed Al; Wittman, Richard S; Delodovici, Francesco; Manini, Nicola (2017). "Novamene: A new class of carbon allotropes". Heliyon. 3 (2): e00242. doi:10.1016/j.heliyon.2017.e00242. PMC . PMID 28217750.

19. ^ Delodovici, Francesco; Manini, Nicola; Wittman, Richard S; Choi, Daniel S; Al Fahim, Mohamed; Burchfield, Larry A (2018). "Protomene: A new carbon allotrope" (PDF). Carbon. 126: 574-579. doi:10.1016/j.carbon.2017.10.069. hdl:2434/546815.

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Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite. In recent decades, many more allotropes have been discovered and researched including ball shapes such as buckminsterfullerene and sheets such as graphene.

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Anders Gustaf Ekeberg was a Swedish analytical chemist who discovered tantalum in 1802

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Anders Gustaf Ekeberg was a Swedish analytical chemist who discovered tantalum in 1802

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From Wikipedia, the free encyclopedia

Anders Gustav Ekeberg was a Swedish scientist, mathematician and expert in Greek literature. His father, Joseph Erik Ekeberg, was a shipbuilder. His uncle was Carl Gustaf Ekeberg.

Anders Gustav Ekeberg attended school at Kalmar, Söderåkra, Vestervik, and Karlskrona. He was a gifted student and enrolled at Uppsala University in 1784, graduating in 1788. His thesis addressed the extraction of oils from seeds. In 1789 and 1790, he traveled and studied in Germany, hearing Martin Heinrich Klaproth lecture in Berlin as well as Christian Ehrenfried Weigel in Greifswald.

In 1794, Anders Gustav Ekeberg began teaching at Uppsala. He was a supporter of Antoine Lavoisier's proposals for systematizing chemical nomenclature. In 1795 he and Pehr von Afzelius published the first article to introduce the modern names for chemical elements such as hydrogen, nitrogen, and oxygen into the Swedish language, "On the Present State of Chemical Sciences".

He was made docent in chemistry in 1794 and experimentator ( laborator) in 1799, working as a demonstrator in the laboratory of Torbern Bergman. In 1798 he lectured on the theory of combustion. In 1799, he was elected a member of the Royal Swedish Academy of Sciences.

Ekeberg had poor health throughout his life. During his childhood a severe cold had impaired his hearing, which was further weakened over the years, so that it hindered his teaching activities. Subsequently, a gas explosion blinded him in one eye.

Ekeberg was portrayed by his friends and students as a kind and gentle man. He died, unmarried, at the age of 46.

Ekeberg analyzed a number of the minerals found at Ytterby and Falun. In 1802 he analyzed specimens of tantalite from Kimito, Finland, and of yttrotantalite from Ytterby, Sweden. He is credited with finding the element tantalum in both.

Ekeberg named the new element after the mythical Ancient Greek demigod Tantalus. According to legend, he was condemned to eternal frustration when he had to stand in water up to his neck, but the water receded as he attempted to drink.

In 2018 the Tantalum-Niobium International Study Center established The Anders Gustaf Ekeberg Tantalum Prize ("Ekeberg Prize"), an annual award to recognize excellence in tantalum research. The Prize will increase awareness of the many unique properties of tantalum products and the applications in which they excel. The inaugural winner of the Ekeberg Prize was Yuri Freeman, for his book "Tantalum and Niobium-Based Capacitors" (Springer, 2018).

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From Wikipedia, the free encyclopedia Anders Gustav Ekeberg was a Swedish scientist, mathematician and expert in Greek literature. His father, Joseph Erik Ekeberg, was a shipbuilder. His uncle was Carl Gustaf Ekeberg. Anders Gustav Ekeberg attended school at Kalmar, Söderåkra, Vestervik, and Karlskrona.

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https://www.aperisolve.com/f79388968433c973214bcfadd625ec62

https://cdn.discordapp.com/attachments/1031539174743998526/1106610228205727825/THE_FINALS_NAMALAPIS.png

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Marble is a metamorphic rock consisting of carbonate minerals that recrystallize under the influence of heat, pressure and aqueous solutions, most commonly calcite (CaCO3) or dolomite (CaMg(CO3)2) and has a crystalline texture of varying thickness.[1] Marble is typically not foliated ( layered), although there are exceptions.

In geology, the term marble refers to metamorphosed limestone, but its use in stonemasonry more broadly encompasses unmetamorphosed limestone.[2] Marble is commonly used for sculpture and as a building material.

The word "marble" derives from the Ancient Greek μάρμαρον ( mármaron),[3] from μάρμαρος ([4]mármaros), "crystalline rock, shining stone",[5] perhaps from the verb μαρμαίρω ([6] R. S. P. Beekes has suggested that a " marmaírō), "to flash, sparkle, gleam"; Pre-Greek origin is probable".[7]

This stem is also the ancestor of the English word "marmoreal," meaning "marble-like."[8] While the English term "marble" resembles the French marbre, most other European languages (with words like "marmoreal") more closely resemble the original Ancient Greek.[9]

Marble is a rock resulting from metamorphism of sedimentary carbonate rocks, most commonly limestone or dolomite (rock). Metamorphism causes variable recrystallization of the original carbonate mineral grains. The resulting marble rock is typically composed of an interlocking mosaic of carbonate crystals. Primary sedimentary textures and structures of the original carbonate rock ( protolith) have typically been modified or destroyed.

Pure white marble is the result of metamorphism of a very pure ( silicate-poor) limestone or dolomite protolith. The characteristic swirls and veins of many colored marble varieties are usually due to various mineral impurities such as clay, silt, sand, iron oxides, or chert which were originally present as grains or layers in the limestone. Green coloration is often due to serpentine resulting from originally magnesium-rich limestone or dolomite with silica impurities. These various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism.[citation needed ]

Acids react with the calcium carbonate in marble, producing carbonic acid (which decomposes quickly to CO ₂ and H ₂O) and other soluble salts :[10]

CaCO₃(s) + 2H⁺(aq) → Ca²⁺(aq) + CO₂(g) + H₂O (l)

Outdoor marble statues, gravestones, or other marble structures are damaged by acid rain whether by carbonation, sulfation or the formation of "black-crust" (accumulation of calcium sulphate, nitrates and carbon particles).[10] Vinegar and other acidic solutions should be avoided in the cleaning of marble products.

Crystallization refers to a method of imparting a glossy more durable finish on to a marble floor (CaCO ₃). It involves polishing the surface with an acidic solution and a steel wool pad on a flooring machine. The chemical reaction below shows a typical process using magnesium fluorosilicate (MgSiF ₆) and hydrochloric acid (HCl) taking place.

CaCO₃(s) + MgSiF₆(l) + 2HCl (l) → MgCl₂(s) + CaSiF₆(s) + CO₂(g) + H₂O(l)

The resulting calcium hexafluorosilicate (CaSiF ₆) is bonded to the surface of the marble. This is harder, more glossy and stain resistant compared to the original surface.

The other often used method of finishing marble is the use of polishing with oxalic acid (H ₂C ₂O ₄), an organic acid. The resulting reaction is as follows.

CaCO₃(s) + H₂C₂O₄(l) → CaC₂O₄(s) + CO₂(g) + H₂O(l)

In this case the calcium oxalate (CaC ₂O ₄) formed in the reaction is washed away with the slurry leaving a surface that has not been chemically changed.[11]

The haloalkaliphilic methylotrophic bacterium Methylophaga murata was isolated from deteriorating marble in the Kremlin.[12] Bacterial and fungal degradation was detected in four samples of marble from Milan Cathedral; black Cladosporium attacked dried acrylic resin[13] using melanin.[14]

Marble

Color

Location

Country

Creole marble

white and blue/black

Pickens County, Georgia

United States

Makrana marble

white

Makrana, Nagaur district, Rajasthan

India

Murphy marble

white

Pickens and Gilmer Counties, Georgia

United States

Nero Marquina marble

black

Markina-Xemein, Bizkaia, Basque County

Spain

Pentelic marble[15]
pure-white, fine-grained semitranslucent

Mount Pentelicus (Πεντελικό όρος), Attica (Ἀττική)

Greece

Prokonnesos marble

white

Marmara Island, Sea of Marmara

Turkey

Rușchița marble[16]
white, pinkish, reddish

Poiana Ruscă Mountains, Caraș-Severin County

Romania

Venčac marble

white

Venčac mountain near Aranđelovac

Serbia

Marble is a rock composed of calcium and magnesium carbonate, mostly white and pink.[1] Common marble varieties are granular limestone or dolomite. The hardness of marble is very high, because the internal structure of the rock is very uniform after long-term natural aging, and the internal stress disappears, so the marble will not be deformed due to temperature, and has strong wear resistance. It is a very popular building material.

The following table is a summary of the features of Marble.[17]

White marble has been prized for its use in sculptures[18] since classical times. This preference has to do with its softness, which made it easier to carve, relative isotropy and homogeneity, and a relative resistance to shattering. Also, the low index of refraction of calcite allows light to penetrate 12.7 to 38 millimeters into the stone before being scattered out, resulting in the characteristic waxy look which brings a lifelike luster to marble sculptures of any kind, which is why many sculptors preferred and still prefer marble for sculpting.[19]

Construction marble is a stone which is composed of calcite, dolomite or serpentine that is capable of taking a polish.[20] More generally in construction, specifically the dimension stone trade, the term marble is used for any crystalline calcitic rock (and some non-calcitic rocks) useful as building stone. For example, Tennessee marble is really a dense granular fossiliferous gray to pink to maroon Ordovician limestone, that geologists call the Holston Formation.

Ashgabat, the capital city of Turkmenistan, was recorded in the 2013 Guinness Book of Records as having the world's highest concentration of white marble buildings.[21]

The extraction of marble is performed by quarrying. Blocks are favoured for most purposes, and can be created through various techniques, including drilling and blasting, water jet and wedge methods.[22] Limestones are often commercially and historically referred to as marble, which differs from the geological definition.

In 1998, marble production was dominated by 4 countries that accounted for almost half of world production of marble and decorative stone. Italy and China were the world leaders, each representing 16% of world production, while Spain and India produced 9% and 8%, respectively.[23]

In 2018 Turkey was the world leader in marble export, with 42% share in global marble trade, followed by Italy with 18% and Greece with 10%. The largest importer of marble in 2018 was China with a 64% market share, followed by India with 11% and Italy with 5%.[24]

United States Edit

According to the United States Geological Survey, U.S. domestic marble production in 2006 was 46,400 tons valued at about $18.1 million, compared to 72,300 tons valued at $18.9 million in 2005. Crushed marble production (for aggregate and industrial uses) in 2006 was 11.8 million tons valued at $116 million, of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate. For comparison, 2005 crushed marble production was 7.76 million tons valued at $58.7 million, of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate. U.S. dimension marble demand is about 1.3 million tons. The DSAN World Demand for (finished) Marble Index has shown a growth of 12% annually for the 2000-2006 period, compared to 10.5% annually for the 2000-2005 period. The largest dimension marble application is tile.

Palestine Edit

The stone and marble industry is one of the largest industries in Palestine, contributing 20-25% of its total industrial revenues, generating USD $400-$450 million in revenue annually. The industry employs 15,000-20,000 workers across the West Bank across 1200-1700 facilities, and amounts to 4.5% of the nation's GDP. The vast majority of the industry's exports are to Israel.

Marble in the geologic sense does not naturally outcrop in Palestine, and that the vast majority of commercially labeled marble produced in Palestine produced would be geologically considered limestone.[25]

Particulate air pollution exposure has been found to be elevated in the marble production industry. Exposure to the dust produced by cutting marble could impair lung function or cause lung disease in workers, such as silicosis. Skin and eye problems are also a potential hazard. Mitigations such as dust filters, or dust suppression are suggested, but more research needs to be carried out on the efficacy of safety measures.[26][25]

In the United States, the Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit) for marble exposure in the workplace as 15 mg/m ³ total exposure and 5 mg/m ³ respiratory exposure over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 10 mg/m ³ total exposure and 5 mg/m ³ respiratory exposure over an 8-hour workday.[27][non sequitur ]

Dust, debris and temperature fluctuations from working marble can endanger the eye health of employees.[28] For the staff involved in marble processing, it is necessary to provide eye protection equipment, and it is recommended to improve the education of all workers on occupational health risks and strengthen preventive measures.[28]

As the favorite medium for Greek and Roman sculptors and architects (see classical sculpture), marble has become a cultural symbol of tradition and refined taste. Its extremely varied and colorful patterns make it a favorite decorative material.[citation needed ]

Places named after the stone include Marblehead, Massachusetts; Marblehead, Ohio; Marble Arch, London; the Sea of Marmara; India's Marble Rocks; and the towns of Marble, Minnesota; Marble, Colorado; Marble Falls, Texas, and Marble Hill, Manhattan, New York. The Elgin Marbles are marble sculptures from the Parthenon in Athens that are on display in the British Museum.[citation needed ]

Total world quarrying production in 2019 was approximately 316 million tonnes; however, quarrying waste accounted for 53% of this total production.[28] In the process of marble mining and processing, there will be a large amount of non-degradable waste, which will cause serious damage to the environment and threaten the life of animals and plants.[1] For example, the poor management of mining activities has resulted in a large amount of waste rocks, and the waste is thrown by the river, polluting the surrounding water sources, causing groundwater pollution, and endangering human health. According to the research of water samples around the marble mine, it was found that the number of cations and anions in the water increased.[1]

Marble[1] sludge waste can be used as a mineral filler in water-based paints.[29] Using ground calcium carbonate as a filler in paint production can improve the brightness, hiding power and application performance of paint, and can also replace expensive pigments such as titanium dioxide.[29] Recycling of marble waste leads to a large amount of waste not being landfilled, reducing environmental pollution, thereby realizing the sustainability of marble. Converting waste to generate economic income and restore degraded soil can improve the environment.

The nature of marble is soft and porous, so it is easily stained by colored liquids and scratches easily. So daily maintenance and cleaning is particularly important.[30]

Prevent sand and dust from contacting the marble surface.[30]

Avoid corroding marble surfaces with alcohol, color and acidic liquids.[30]

As a floor material, marble is the easiest to scratch. You can first use a vacuum cleaner to suck away the grit and dust on the marble floor, and then use a steam cleaner to remove other dirt.[31]

A mild, pH-neutral, non-abrasive soap should be used for cleaning marble surfaces. Wipe with a soft foam cotton or rag.[31]

1. ^

2. Kearey, Philip (2001). ^ Dictionary of Geology, Penguin Group, London and New York, p. 163. ISBN 978-0-14-051494-0

3. ^ μάρμαρον[permanent dead link ] , Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus Digital Library

4. ^ Marble, Compact Oxford English Dictionary[dead link ] . Askoxford.com. Retrieved on 2011-09-30.

5. ^ "Crystallization vs. Oxalic Acid Polishing" (PDF). 3M.

6. ^ Doronina NV; Li TsD; Ivanova EG; Trotsenko IuA. (2005). "Methylophaga murata sp. nov.: a haloalkaliphilic aerobic methylotroph from deteriorating marble". Mikrobiologiia. 74 (4): 511-9. PMID 16211855.

7. ^ Cappitelli F; Principi P; Pedrazzani R; Toniolo L; Sorlini C (2007). "Bacterial and fungal deterioration of the Milan Cathedral marble treated with protective synthetic resins". Science of the Total Environment. 385 (1-3): 172-81. Bibcode:2007ScTEn.385..172C. doi:10.1016/j.scitotenv.2007.06.022. PMID 17658586.

8. ^ Cappitelli F; Nosanchuk JD; Casadevall A; Toniolo L; Brusetti L; Florio S; Principi P; Borin S; Sorlini C (Jan 2007). "Synthetic consolidants attacked by melanin-producing fungi: case study of the biodeterioration of Milan (Italy) cathedral marble treated with acrylics". Applied and Environmental Microbiology. 73 (1): 271-7. Bibcode:2007ApEnM..73..271C. doi:10.1128/AEM.02220-06. PMC 1797126. PMID 17071788.

9. ^ "RAPORT DE ȚARĂ. Domul din Milano a fost reconstruit cu marmură de Rușchița". Archived from the original on 2013-05-14.

10. ^ PROCEEDINGS 4th International Congress on "Science and Technology for the Safeguard of Cultural Heritage in the Mediterranean Basin" VOL. I. Angelo Ferrari. p. 371. ISBN 9788896680315. white marble prized for use to make sculptures.

11. "Marble", Britannica Online Encyclopaedia. Britannica.com.; Clarke, Michael, ^ The Concise Oxford Dictionary of Art Terms, p.148, 2001, Oxford University Press, ISBN 9780192800435

12. ^ Marble Institute of America pp. 223 Glossary

13. ^ Rathore, S. S.; Bhandari, S. (2006-03-30). "Controlled Fracture Growth by Blasting While Protecting Damages to Remaining Rock". Rock Mechanics and Rock Engineering. 40 (3): 317-326. doi:10.1007/s00603-005-0080-5. ISSN 0723-2632.

14. ^ Strategic positioning study of the marble branch Archived 2005-11-10 at the Wayback Machine. CEPI Brief N° 6. tunisianindustry.nat.tn

15. Salem, Hilmi S. (2021-02-02). "Evaluation of the Stone and Marble Industry in Palestine: environmental, geological, health, socioeconomic, cultural, and legal perspectives, in view of sustainable development". Environmental Science and Pollution Research. doi:10.1007/s11356-021-12526-4. ISSN 0944-1344.

16. Foja, A.F. (1993) ^ Marble industry: its socioeconomic, environmental and health effects among marble worker/producer households in Romblon. Philippines University Thesis. fao.org

17. ^ Khorshed, Enjy A. E.; El-Naggar, Safaa A.; El-Gohary, Samia S.; Awad, Ahmed M. B.; Ahmed, Amani S. (2022). "Occupational ocular health problems among marble workers at Shaq El Tho'ban industrial area in Egypt". Environmental Science and Pollution Research. 29 (25): 37445-37457. doi:10.1007/s11356-021-18410-5. ISSN 0944-1344. PMC 9106598. PMID 35066853.

18. Marras, Graziella; Carcangiu, Gianfranco; Meloni, Paola; Careddu, Nicola (2022). "Circular economy in marble industry: From stone scraps to sustainable water-based paints". Construction and Building Materials. 325: 126768. doi:10.1016/j.conbuildmat.2022.126768.

19. ^

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Marble is a metamorphic rock consisting of carbonate minerals that recrystallize under the influence of heat, pressure and aqueous solutions, most commonly calcite (CaCO3) or dolomite (CaMg(CO3)2) and has a crystalline texture of varying thickness.[1] Marble is typically not foliated ( layered), although there are exceptions.

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https://en.wikipedia.org/wiki/Lapis_lazuli

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Lapis lazuli (), or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color.

As early as the 7th millennium BCE, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in northeast Afghanistan.

Lapis lazuli artifacts, dated to 7570 BCE, have been found at Bhirrana, which is the oldest site of Indus Valley Civilisation. Lapis was highly valued by the Indus Valley Civilisation (7570-1900 BCE). Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and as far away as Mauritania. It was used in the funeral mask of Tutankhamun (1341-1323 BCE).

By the end of the Middle Ages, lapis lazuli began to be exported to Europe, where it was ground into powder and made into ultramarine, the finest and most expensive of all blue pigments. Ultramarine was used by some of the most important artists of the Renaissance and Baroque, including Masaccio, Perugino, Titian and Vermeer, and was often reserved for the clothing of the central figures of their paintings, especially the Virgin Mary. Ultramarine has also been found in dental tartar of medieval nuns and scribes.

Mines in northeast Afghanistan continue to be a major source of lapis lazuli. Important amounts are also produced from mines west of Lake Baikal in Russia, and in the Andes mountains in Chile. Smaller quantities are mined in Pakistan, Italy, Mongolia, the United States, and Canada.

Lapis is the Latin word for "stone" and lazulī is the genitive form of the Medieval Latin lazulum, which is taken from the Arabic لازورد lāzaward, itself from the Persian لاجورد lājevard, which is the name of the stone in Persian, and also of a place where lapis lazuli was mined. Lazulum is etymologically related to the color blue and used as a root for the word for blue in several languages, including Spanish and Portuguese azul.

The most important mineral component of lapis lazuli is lazurite (25% to 40%), a blue feldspathoid silicate mineral with the formula (Na,Ca) ₈(AlSiO ₄) ₆(S,SO ₄,Cl) ₁₋₂. Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Some samples of lapis lazuli contain augite, diopside, enstatite, mica, hauynite, hornblende, nosean, and sulfur-rich löllingite geyerite.

Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism.

The intense blue color is due to the presence of the trisulfur radical anion ( −) in the crystal. An electronic excitation of one electron from the highest doubly filled molecular orbital (No. 24) into the lowest singly occupied orbital (No. 25) results in a very intense absorption line at λ max ~617 nm.

Lapis lazuli is found in limestone in the Kokcha River valley of Badakhshan province in northeastern Afghanistan, where the Sar-e-Sang mine deposits have been worked for more than 6,000 years. Afghanistan was the source of lapis for the ancient Egyptian and Mesopotamian civilizations, as well as the later Greeks and Romans. Ancient Egyptians obtained the material through trade with Aryans[citation needed ]. During the height of the Indus Valley Civilisation, approximately 2000 BCE, the Harappan colony, now known as Shortugai, was established near the lapis mines.

According to the Sorbonne's mineralogist Pierre Bariand's leading work on the sources of lapis lazuli in modern times, and to references in Afghanistan's Blue Treasure: Lapis Lazuli (2011) by Lailee McNair Bakhtiar, the lapis lazuli is found in "caves" not traditionally considered "mines" and the stone lapis lazuli is from the primary source of the Hindu Kush Mountains in Afghanistan's Kochka River Valley and not in Pakistan.[citation needed ]

In addition to the Afghan deposits, lapis is also extracted in the Andes (near Ovalle, Chile); and to the west of Lake Baikal in Siberia, Russia, at the Tultui Lazurite deposit. It is mined in smaller amounts in Angola, Argentina, Burma, Pakistan, Canada, Italy, India, and in the United States in California and Colorado.

Lapis takes an excellent polish and can be made into jewelry, carvings, boxes, mosaics, ornaments, small statues, and vases. During the Renaissance, lapis was ground and processed to make the pigment ultramarine for use in frescoes and oil painting. Its usage as a pigment in oil paint largely ended during the early 19th century, when a chemically identical synthetic variety became available.

Lapis lazuli is commercially synthesized or simulated by the Gilson process, which is used to make artificial ultramarine and hydrous zinc phosphates. It may also be substituted by spinel or sodalite, or by dyed jasper or howlite.

Natural ultramarine pigment made from ground lapis lazuli. During the Middle Ages and Renaissance it was the most expensive pigment available (gold being second) and was often reserved for depicting the robes of Angels or the Virgin Mary

Lapis lazuli has been mined in Afghanistan and exported to the Mediterranean world and South Asia since the Neolithic age, along the ancient trade route between Afghanistan and the Indus Valley, dating to the 7th millennium BCE. Quantities of these beads have also been found at 4th millennium BCE settlements in Northern Mesopotamia, and at the Bronze Age site of Shahr-e Sukhteh in southeast Iran (3rd millennium BCE). A dagger with a lapis handle, a bowl inlaid with lapis, amulets, beads, and inlays representing eyebrows and beards, were found in the Royal Tombs of the Sumerian city-state of Ur from the 3rd Millennium BCE.

Lapis was also used in ancient Mesopotamia by the Akkadians, Assyrians, and Babylonians for seals and jewelry. It is mentioned several times in the Mesopotamian poem, the Epic of Gilgamesh (17th-18th Century BCE), one of the oldest known works of literature. The Statue of Ebih-Il, a 3rd millennium BCE statue found in the ancient city-state of Mari in modern-day Syria, now in the Louvre, uses lapis lazuli inlays for the irises of the eyes.

In ancient Egypt, lapis lazuli was a favorite stone for amulets and ornaments such as scarabs. Lapis jewelry has been found at excavations of the Predynastic Egyptian site Naqada (3300-3100 BCE). At Karnak, the relief carvings of Thutmose III (1479-1429 BCE) show fragments and barrel-shaped pieces of lapis lazuli being delivered to him as tribute. Powdered lapis was used as eyeshadow by Cleopatra.

Jewelry made of lapis lazuli has also been found at Mycenae attesting to relations between the Myceneans and the developed civilizations of Egypt and the East.

Pliny the Elder wrote that lapis lazuli is "opaque and sprinkled with specks of gold". Because the stone combines the blue of the heavens and golden glitter of the sun, it was emblematic of success in the old Jewish tradition. In the early Christian tradition lapis lazuli was regarded as the stone of Virgin Mary.

In late classical times and as late as the Middle Ages, lapis lazuli was often called sapphire ( sapphirus in Latin, sappir in Hebrew), though it had little to do with the stone today known as the blue corundum variety sapphire. In his book on stones, the Greek scientist Theophrastus described "the sapphirus, which is speckled with gold," a description which matches lapis lazuli.

There are many references to sapphires in the Old Testament, but most scholars agree that, since sapphire was not known before the Roman Empire, they most likely are references to lapis lazuli. For instance, Exodus 24:10: "And they saw the God of Israel, and there was under his feet as it were a paved work of a sapphire stone..." (KJV). The term used in the Latin Vulgate Bible in this citation is "lapidus sapphiri", the term for lapis lazuli. Modern translations of the Bible, such as the New Living Translation Second Edition, refer to lapis lazuli in most instances instead of sapphire.

Bakhtiar, Lailee McNair, Afghanistan's Blue Treasure Lapis Lazuli, Front Porch Publishing, 2011, ISBN 978-0615573700

Bariand, Pierre, "Lapis Lazuli", Mineral Digest, Vol 4 Winter 1972.

Bowersox, Gary W.; Chamberlin, Bonita E. (1995). "Gemstones of Afghanistan". Tucson, AZ: Geoscience Press. .

Herrmann, Georgina, "Lapis Lazuli: The Early Phases of Its Trade", Oxford University Dissertation, 1966.

Korzhinskij, D. S., "Gisements bimetasomatiques de philogophite et de lazurite de l'Archen du pribajkale", Traduction par Mr. Jean Sagarzky-B.R.G.M., 1944.

Lapparent A. F., Bariand, P. et Blaise, J., "Une visite au gisement de lapis lazuli de Sar-e-Sang du Hindu Kouch, Afghanistan," C.R. Somm.S.G.P.p. 30, 1964.

Oldershaw, Cally (2003). "Firefly Guide to Gems". Toronto: Firefly Books. .

Wise, Richard W., Secrets of the Gem Trade: The Connoisseur's Guide to Precious Gemstones, 2016 ISBN 9780972822329

Wyart J. Bariand P, Filippi J., "Le Lapis Lazuli de Sar-e-SAng", Revue de Geographie Physique et de Geologie Dynamique (2) Vol. XIV Pasc. 4 pp. 443-448, Paris, 1972.

# data[].attributes.attachment_link.description
Lapis lazuli (), or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. As early as the 7th millennium BCE, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in northeast Afghanistan.

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“Crystalline” redirects here. For the Björk song, see Crystalline (song).

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H O A C S N I R H M E - underlined elements

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H O A C S N I R H M E - underlined elements

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red cross
Xenon (Xe-54)
Caesium (Cs-55)
Lanthanum (La-57)
Gold (Au-79)

black cross
Hassium (Hs-108)

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https://en.wikipedia.org/wiki/Protoporphyrin_IX

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The person on the 20 krona note

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DHL space-  being pressed

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Pronunciation

​(TAN-təl-əm)

Appearance

gray blue

(Atomic number Z)

73

Block

d-block

Electron configuration

[ Xe] 4f ¹⁴ 5d ³ 6s ²

Electrons per shell

2, 8, 18, 32, 11, 2

at Phase STP
solid

Density (at 20° C)

16.678 g/cm ³ [3]

when liquid (at m.p.)

15 g/cm ³

Vapor pressure

P (Pa)

1

10

100

1 k

10 k

100 k

at T (K)

3297

3597

3957

4395

4939

5634

Oxidation states

−3, −1, 0, +1, +2, +3, +4, +5 (a mildly acidic oxide)

Ionization energies

1st: 761 kJ/mol

2nd: 1500 kJ/mol

Spectral lines of tantalum

Natural occurrence
primordial

Crystal structure

​ body-centered cubic (bcc)[3] ( cI2)

Lattice constant

a = 330.29 pm (at 20 °C)[3]

Magnetic ordering

paramagnetic[4]

Molar magnetic susceptibility

+154.0×10 −6 cm ³/mol (293 K)[5]

Speed of sound thin rod

3400 m/s (at 20 °C)

Discovery

Anders Gustaf Ekeberg (1802)

Category: Tantalum
| references

Tantalum is a chemical element; it has symbol Ta and atomic number 73. Previously known as tantalium, it is named after Tantalus, a figure in Greek mythology. Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as components of strong high-melting-point alloys. It is a group 5 element, along with vanadium and niobium, and it always occurs in geologic sources together with the chemically similar niobium, mainly in the mineral groups tantalite, columbite and coltan.

The chemical inertness and very high melting point of tantalum make it valuable for laboratory and industrial equipment such as reaction vessels and vacuum furnaces. It is used in tantalum capacitors for electronic equipment such as computers. It is being investigated for use as a material for high-quality superconducting resonators in quantum processors. Tantalum is considered a technology-critical element by the European Commission.

Tantalum was discovered in Sweden in 1802 by Anders Ekeberg, in two mineral samples - one from Sweden and the other from Finland. One year earlier, Charles Hatchett had discovered columbium (now niobium). In 1809, the English chemist William Hyde Wollaston compared the oxides of columbium and tantalum, columbite and tantalite. Although the two oxides had different measured densities of 5.918 g/cm ³ and 7.935 g/cm ³, he concluded that they were identical and kept the name tantalum. After Friedrich Wöhler confirmed these results, it was thought that columbium and tantalum were the same element. This conclusion was disputed in 1846 by the German chemist Heinrich Rose, who argued that there were two additional elements in the tantalite sample, and he named them after the children of Tantalus: niobium (from Niobe, the goddess of tears), and pelopium (from Pelops). The supposed element "pelopium" was later identified as a mixture of tantalum and niobium, and it was found that the niobium was identical to the columbium already discovered in 1801 by Hatchett.

The differences between tantalum and niobium were demonstrated unequivocally in 1864 by Christian Wilhelm Blomstrand, and Henri Etienne Sainte-Claire Deville, as well as by Louis J. Troost, who determined the empirical formulas of some of their compounds in 1865. Further confirmation came from the Swiss chemist Jean Charles Galissard de Marignac, in 1866, who proved that there were only two elements. These discoveries did not stop scientists from publishing articles about the so-called until 1871. De Marignac was the first to produce the metallic form of tantalum in 1864, when he reduced tantalum chloride by heating it in an atmosphere of hydrogen. Early investigators had only been able to produce impure tantalum, and the first relatively pure ductile metal was produced by Werner von Bolton in Charlottenburg in 1903. Wires made with metallic tantalum were used for light bulb filaments until tungsten replaced it in widespread use.

The name tantalum was derived from the name of the mythological Tantalus, the father of Niobe in Greek mythology. In the story, he had been punished after death by being condemned to stand knee-deep in water with perfect fruit growing above his head, both of which eternally tantalized him. (If he bent to drink the water, it drained below the level he could reach, and if he reached for the fruit, the branches moved out of his grasp.) Anders Ekeberg wrote "This metal I call tantalum ... partly in allusion to its incapacity, when immersed in acid, to absorb any and be saturated."

For decades, the commercial technology for separating tantalum from niobium involved the fractional crystallization of potassium heptafluorotantalate away from potassium oxypentafluoroniobate monohydrate, a process that was discovered by Jean Charles Galissard de Marignac in 1866. This method has been supplanted by solvent extraction from fluoride-containing solutions of tantalum.

Tantalum is dark (blue-gray), dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity. The metal is highly resistant to corrosion by acids: at temperatures below 150 ° C tantalum is almost completely immune to attack by the normally aggressive aqua regia. It can be dissolved with hydrofluoric acid or acidic solutions containing the fluoride ion and sulfur trioxide, as well as with molten potassium hydroxide. Tantalum's high melting point of 3017 °C (boiling point 5458 °C) is exceeded among the elements only by tungsten, rhenium and osmium for metals, and carbon.

Tantalum exists in two crystalline phases, alpha and beta. The alpha phase is stable at all temperatures up to the melting point and has body-centered cubic structure with lattice constant a = 0.33029 nm at 20 °C. It is relatively ductile, has Knoop hardness 200-400 HN and electrical resistivity 15-60 μΩ⋅cm. The beta phase is hard and brittle; its crystal symmetry is tetragonal (space group P42/mnm, a = 1.0194 nm, c = 0.5313 nm), Knoop hardness is 1000-1300 HN and electrical resistivity is relatively high at 170-210 μΩ⋅cm. The beta phase is metastable and converts to the alpha phase upon heating to 750-775 °C. Bulk tantalum is almost entirely alpha phase, and the beta phase usually exists as thin films obtained by magnetron sputtering, chemical vapor deposition or electrochemical deposition from a eutectic molten salt solution.

Natural tantalum consists of two stable isotopes: 180mTa (0.012%) and ¹⁸¹Ta (99.988%). 180mTa ( m denotes a metastable state) is predicted to decay in three ways: isomeric transition to the ground state of ¹⁸⁰Ta, beta decay to ¹⁸⁰ W, or electron capture to ¹⁸⁰ Hf. However, radioactivity of this nuclear isomer has never been observed, and only a lower limit on its half-life of 2.0 × 10 ¹⁶ years has been set. The ground state of ¹⁸⁰Ta has a half-life of only 8 hours. 180mTa is the only naturally occurring nuclear isomer (excluding radiogenic and cosmogenic short-lived nuclides). It is also the rarest primordial isotope in the Universe, taking into account the elemental abundance of tantalum and isotopic abundance of 180m Ta in the natural mixture of isotopes (and again excluding radiogenic and cosmogenic short-lived nuclides).

Tantalum has been examined theoretically as a " salting" material for nuclear weapons ( cobalt is the better-known hypothetical salting material). An external shell of ¹⁸¹Ta would be irradiated by the intensive high-energy neutron flux from a hypothetical exploding nuclear weapon. This would transmute the tantalum into the radioactive isotope ¹⁸²Ta, which has a half-life of 114.4 days and produces gamma rays with approximately 1.12 million electron-volts (MeV) of energy apiece, which would significantly increase the radioactivity of the nuclear fallout from the explosion for several months. Such "salted" weapons have never been built or tested, as far as is publicly known, and certainly never used as weapons.

Tantalum can be used as a target material for accelerated proton beams for the production of various short-lived isotopes including ⁸Li, ⁸⁰Rb, and ¹⁶⁰ Yb.

Tantalum forms compounds in oxidation states −III to +V. Most commonly encountered are oxides of Ta(V), which includes all minerals. The chemical properties of Ta and Nb are very similar. In aqueous media, Ta only exhibit the +V oxidation state. Like niobium, tantalum is barely soluble in dilute solutions of hydrochloric, sulfuric, nitric and phosphoric acids due to the precipitation of hydrous Ta(V) oxide. In basic media, Ta can be solubilized due to the formation of polyoxotantalate species.

Oxides, nitrides, carbides, sulfides

Tantalum pentoxide (Ta ₂O ₅) is the most important compound from the perspective of applications. Oxides of tantalum in lower oxidation states are numerous, including many defect structures, and are lightly studied or poorly characterized.

As in the cases of other refractory metals, the hardest known compounds of tantalum are nitrides and carbides. Tantalum carbide, TaC, like the more commonly used tungsten carbide, is a hard ceramic that is used in cutting tools. Tantalum(III) nitride is used as a thin film insulator in some microelectronic fabrication processes.

The best studied chalcogenide is TaS ₂, a layered semiconductor, as seen for other transition metal dichalcogenides. A tantalum-tellurium alloy forms quasicrystals.

Tantalum halides span the oxidation states of +5, +4, and +3. Tantalum pentafluoride (TaF ₅) is a white solid with a melting point of 97.0 °C. The anion [TaF ₇] ²⁻ is used for its separation from niobium. The chloride , which exists as a dimer, is the main reagent in synthesis of new Ta compounds. It hydrolyzes readily to an oxychloride. The lower halides and , feature Ta-Ta bonds.

Organotantalum compounds include pentamethyltantalum, mixed alkyltantalum chlorides, alkyltantalum hydrides, alkylidene complexes as well as cyclopentadienyl derivatives of the same. Diverse salts and substituted derivatives are known for the hexacarbonyl [Ta(CO) ₆] − and related isocyanides.

Ta(CH₃)₅.

Tantalite, Pilbara district, Australia

Tantalum is estimated to make up about 1 ppm or 2 ppm of the Earth's crust by weight. There are many species of tantalum minerals, only some of which are so far being used by industry as raw materials: tantalite (a series consisting of tantalite-(Fe), tantalite-(Mn) and tantalite-(Mg)), microlite (now a group name), wodginite, euxenite (actually euxenite-(Y)), and polycrase (actually polycrase-(Y)). Tantalite ( Fe, Mn)Ta ₂ O ₆ is the most important mineral for tantalum extraction. Tantalite has the same mineral structure as columbite ( Fe, Mn) (Ta, Nb) ₂ O ₆; when there is more tantalum than niobium it is called tantalite and when there is more niobium than tantalum is it called columbite (or niobite). The high density of tantalite and other tantalum containing minerals makes the use of gravitational separation the best method. Other minerals include samarskite and fergusonite.

Tantalum producers in 2015 with Rwanda being the main producer

Australia was the main producer of tantalum prior to the 2010s, with Global Advanced Metals (formerly known as Talison Minerals) being the largest tantalum mining company in that country. They operate two mines in Western Australia, Greenbushes in the southwest and Wodgina in the Pilbara region. The Wodgina mine was reopened in January 2011 after mining at the site was suspended in late 2008 due to the global financial crisis. Less than a year after it reopened, Global Advanced Metals announced that due to again "... softening tantalum demand ...", and other factors, tantalum mining operations were to cease at the end of February 2012. Wodgina produces a primary tantalum concentrate which is further upgraded at the Greenbushes operation before being sold to customers. Whereas the large-scale producers of niobium are in Brazil and Canada, the ore there also yields a small percentage of tantalum. Some other countries such as China, Ethiopia, and Mozambique mine ores with a higher percentage of tantalum, and they produce a significant percentage of the world's output of it. Tantalum is also produced in Thailand and Malaysia as a by-product of the tin mining there. During gravitational separation of the ores from placer deposits, not only is cassiterite (SnO ₂) found, but a small percentage of tantalite also included. The slag from the tin smelters then contains economically useful amounts of tantalum, which is leached from the slag.

Tantalum producers in 2006 with Australia being the main producer

World tantalum mine production has undergone an important geographic shift since the start of the 21st century when production was predominantly from Australia and Brazil. Beginning in 2007 and through 2014, the major sources of tantalum production from mines dramatically shifted to the Democratic Republic of the Congo, Rwanda, and some other African countries. Future sources of supply of tantalum, in order of estimated size, are being explored in Saudi Arabia, Egypt, Greenland, China, Mozambique, Canada, Australia, the United States, Finland, and Brazil.

Tantalum is considered a conflict resource. Coltan, the industrial name for a columbite- tantalite mineral from which niobium and tantalum are extracted, can also be found in Central Africa, which is why tantalum is being linked to warfare in the Democratic Republic of the Congo (formerly Zaire). According to an October 23, 2003 United Nations report, the smuggling and exportation of coltan has helped fuel the war in the Congo, a crisis that has resulted in approximately 5.4 million deaths since 1998 - making it the world's deadliest documented conflict since World War II. Ethical questions have been raised about responsible corporate behavior, human rights, and endangering wildlife, due to the exploitation of resources such as coltan in the armed conflict regions of the Congo Basin. The United States Geological Survey reports in its yearbook that this region produced a little less than 1% of the world's tantalum output in 2002-2006, peaking at 10% in 2000 and 2008. USGS data published in January 2021 indicated that close to 40% of the world's tantalum mine production came from the Democratic Republic of the Congo, with another 18% coming from neighboring Rwanda and Burundi.

Time trend of tantalum production until 2012[57]

Several steps are involved in the extraction of tantalum from tantalite. First, the mineral is crushed and concentrated by gravity separation. This is generally carried out near the mine site.

The refining of tantalum from its ores is one of the more demanding separation processes in industrial metallurgy. The chief problem is that tantalum ores contain significant amounts of niobium, which has chemical properties almost identical to those of Ta. A large number of procedures have been developed to address this challenge.

In modern times, the separation is achieved by hydrometallurgy. Extraction begins with leaching the ore with hydrofluoric acid together with sulfuric acid or hydrochloric acid. This step allows the tantalum and niobium to be separated from the various non-metallic impurities in the rock. Although Ta occurs as various minerals, it is conveniently represented as the pentoxide, since most oxides of tantalum(V) behave similarly under these conditions. A simplified equation for its extraction is thus:

Completely analogous reactions occur for the niobium component, but the hexafluoride is typically predominant under the conditions of the extraction.

These equations are simplified: it is suspected that bisulfate (HSO ₄−) and chloride compete as ligands for the Nb(V) and Ta(V) ions, when sulfuric and hydrochloric acids are used, respectively. The tantalum and niobium fluoride complexes are then removed from the aqueous solution by liquid-liquid extraction into organic solvents, such as cyclohexanone, octanol, and methyl isobutyl ketone. This simple procedure allows the removal of most metal-containing impurities (e.g. iron, manganese, titanium, zirconium), which remain in the aqueous phase in the form of their fluorides and other complexes.

Separation of the tantalum from niobium is then achieved by lowering the ionic strength of the acid mixture, which causes the niobium to dissolve in the aqueous phase. It is proposed that oxyfluoride H ₂[NbOF ₅] is formed under these conditions. Subsequent to removal of the niobium, the solution of purified H ₂[TaF ₇] is neutralised with aqueous ammonia to precipitate hydrated tantalum oxide as a solid, which can be calcined to tantalum pentoxide (Ta ₂O ₅).

Instead of hydrolysis, the H ₂[TaF ₇] can be treated with potassium fluoride to produce potassium heptafluorotantalate:

Unlike H ₂[TaF ₇], the potassium salt is readily crystallized and handled as a solid.

K ₂[TaF ₇] can be converted to metallic tantalum by reduction with sodium, at approximately 800 °C in molten salt.

In an older method, called the Marignac process, the mixture of H ₂[TaF ₇] and H ₂[NbOF ₅] was converted to a mixture of K ₂[TaF ₇] and K ₂[NbOF ₅], which was then separated by fractional crystallization, exploiting their different water solubilities.

Tantalum can also be refined by electrolysis, using a modified version of the Hall-Héroult process. Instead of requiring the input oxide and output metal to be in liquid form, tantalum electrolysis operates on non-liquid powdered oxides. The initial discovery came in 1997 when Cambridge University researchers immersed small samples of certain oxides in baths of molten salt and reduced the oxide with electric current. The cathode uses powdered metal oxide. The anode is made of carbon. The molten salt at 1,000 °C (1,830 °F) is the electrolyte. The first refinery has enough capacity to supply 3-4% of annual global demand.

All welding of tantalum must be done in an inert atmosphere of argon or helium in order to shield it from contamination with atmospheric gases. Tantalum is not solderable. Grinding tantalum is difficult, especially so for annealed tantalum. In the annealed condition, tantalum is extremely ductile and can be readily formed as metal sheets.

Tantalum electrolytic capacitor

The major use for tantalum, as the metal powder, is in the production of electronic components, mainly capacitors and some high-power resistors. Tantalum electrolytic capacitors exploit the tendency of tantalum to form a protective oxide surface layer, using tantalum powder, pressed into a pellet shape, as one "plate" of the capacitor, the oxide as the dielectric, and an electrolytic solution or conductive solid as the other "plate". Because the dielectric layer can be very thin (thinner than the similar layer in, for instance, an aluminium electrolytic capacitor), a high capacitance can be achieved in a small volume. Because of the size and weight advantages, tantalum capacitors are attractive for portable telephones, personal computers, automotive electronics and cameras.

Tantalum is also used to produce a variety of alloys that have high melting points, strength, and ductility. Alloyed with other metals, it is also used in making carbide tools for metalworking equipment and in the production of superalloys for jet engine components, chemical process equipment, nuclear reactors, missile parts, heat exchangers, tanks, and vessels. Because of its ductility, tantalum can be drawn into fine wires or filaments, which are used for evaporating metals such as aluminium. Since it resists attack by body fluids and is nonirritating, tantalum is widely used in making surgical instruments and implants. For example, porous tantalum coatings are used in the construction of orthopedic implants due to tantalum's ability to form a direct bond to hard tissue.

Tantalum is inert against most acids except hydrofluoric acid and hot sulfuric acid, and hot alkaline solutions also cause tantalum to corrode. This property makes it a useful metal for chemical reaction vessels and pipes for corrosive liquids. Heat exchanging coils for the steam heating of hydrochloric acid are made from tantalum. Tantalum was extensively used in the production of ultra high frequency electron tubes for radio transmitters. Tantalum is capable of capturing oxygen and nitrogen by forming nitrides and oxides and therefore helped to sustain the high vacuum needed for the tubes when used for internal parts such as grids and plates.

Bimetallic coins minted by the Bank of Kazakhstan with silver ring and tantalum center. These two feature the Apollo-Soyuz and the International Space Station

Tantalum was used by NASA to shield components of spacecraft, such as and , from radiation. The high melting point and oxidation resistance led to the use of the metal in the production of vacuum furnace parts. Tantalum is extremely inert and is therefore formed into a variety of corrosion resistant parts, such as thermowells, valve bodies, and tantalum fasteners. Due to its high density, shaped charge and explosively formed penetrator liners have been constructed from tantalum. Tantalum greatly increases the armor penetration capabilities of a shaped charge due to its high density and high melting point.

It is also occasionally used in precious watches e.g. from Audemars Piguet, F.P. Journe, Hublot, Montblanc, Omega, and Panerai. Medical researcher Gerald L. Burke first observed in 1940 that tantalum is also highly bio-inert and could be used safely as an orthopedic implant material. The high stiffness of tantalum makes it necessary to use it as highly porous foam or scaffold with lower stiffness for hip replacement implants to avoid stress shielding. Because tantalum is a non-ferrous, non-magnetic metal, these implants are considered to be acceptable for patients undergoing MRI procedures. The oxide is used to make special high refractive index glass for camera lenses.

Tantalum receives far less attention in the environmental field than it does in other geosciences. Upper Crust Concentration (UCC) and the Nb/Ta ratio in the upper crust and in minerals are available because these measurements are useful as a geochemical tool. The latest value for upper crust concentration is 0.92 ppm, and the Nb/Ta(w/w) ratio stands at 12.7.

Little data is available on tantalum concentrations in the different environmental compartments, especially in natural waters where reliable estimates of 'dissolved' tantalum concentrations in seawater and freshwaters have not even been produced. Some values on dissolved concentrations in oceans have been published, but they are contradictory. Values in freshwaters fare little better, but, in all cases, they are probably below 1 ng L −1, since 'dissolved' concentrations in natural waters are well below most current analytical capabilities. Analysis requires pre-concentration procedures that, for the moment, do not give consistent results. And in any case, tantalum appears to be present in natural waters mostly as particulate matter rather than dissolved.

Values for concentrations in soils, bed sediments and atmospheric aerosols are easier to come by. Values in soils are close to 1 ppm and thus to UCC values. This indicates detrital origin. For atmospheric aerosols the values available are scattered and limited. When tantalum enrichment is observed, it is probably due to loss of more water-soluble elements in aerosols in the clouds.

Pollution linked to human use of the element has not been detected. Tantalum appears to be a very conservative element in biogeochemical terms, but its cycling and reactivity are still not fully understood.

Compounds containing tantalum are rarely encountered in the laboratory. The metal is highly biocompatible and is used for body implants and coatings, therefore attention may be focused on other elements or the physical nature of the chemical compound.

People can be exposed to tantalum in the workplace by breathing it in, skin contact, or eye contact. The Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit) for tantalum exposure in the workplace as 5 mg/m ³ over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 5 mg/m ³ over an 8-hour workday and a short-term limit of 10 mg/m ³. At levels of 2500 mg/m ³, tantalum dust is immediately dangerous to life and health.

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12. ^ Hermann, R. (1871). "Fortgesetzte Untersuchungen über die Verbindungen von Ilmenium und Niobium, sowie über die Zusammensetzung der Niobmineralien (Further research about the compounds of ilmenium and niobium, as well as the composition of niobium minerals)". Journal für Praktische Chemie (in German). 3 (1): 373-427. doi:10.1002/prac.18710030137.

13. ^ Colakis, Marianthe; Masello, Mary Joan (2007-06-30). "Tantalum". Classical Mythology & More: A Reader Workbook. Bolchazy-Carducci Publishers. ISBN 978-0-86516-573-1.

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Pronunciation ​(TAN-təl-əm ) Appearance gray blue (Atomic number Z) 73 Block d-block Electron configuration [ Xe] 4f 14 5d 3 6s 2 Electrons per shell 2, 8, 18, 32, 11, 2 at Phase STP solid Density (at 20° C) 16.678 g/cm 3 [3] when liquid (at m.p.)

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From Wikipedia, the free encyclopedia

CNS or Crystallography and NMR system, is a software library for computational structural biology. It is an offshoot of X-PLOR and uses much of the same syntax. It is used in the fields of X-ray crystallography and NMR spectroscopy of biological macromolecules.

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Crystallography and NMR system - Wikipedia

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C N S

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USS Nautilus - first nuclear-powered submarine

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USS Nautilus - first nuclear-powered submarine

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Class overview

Builders
General Dynamics

Operators

United States Navy

Preceded by

Tang-class submarine

Succeeded by
USS Seawolf

Built

1952

In commission

1954-1980

History

United States

Name
Nautilus

Namesake

Captain Nemo's " Nautilus" submarine[1]

Awarded

2 August 1951

Builder
General Dynamics

Laid down

14 June 1952

Launched

21 January 1954

Sponsored by

Mamie Eisenhower ( First Lady of the United States)

Completed

22 April 1955

Commissioned

30 September 1954

Decommissioned

3 March 1980

Stricken

3 March 1980

Status
Museum ship

General characteristics

Type
Nuclear submarine

Displacement

3,533 long tons (3,590 t) (surface)

4,092 long tons (4,158 t) (submerged)[2]

Length

320 ft (97.5 m)

Beam

28 ft (8.5 m)

Draft

26 ft (7.9 m)

Installed power

13,400 hp (10,000 kW)[4]

Propulsion

STR nuclear reactor (later redesignated S2W), geared steam turbines, two shafts

Speed

23 kn (43 km/h; 26 mph)[3]

Complement

13 officers, 92 enlisted

Armament

6 torpedo tubes

U.S.S. Nautilus (Nuclear Submarine)

Location
Groton, Connecticut

Built

1952-1955, (commissioned 1954)

Architect
General Dynamics Corporation

NRHP reference No.
79002653

Added to NRHP

16 May 1979[5]

Designated NHL

20 May 1982[6]

USS Nautilus (SSN-571) was the world's first operational nuclear-powered submarine and the first submarine to complete a submerged transit of the North Pole on 3 August 1958. Her initial commanding officer was Eugene "Dennis" Wilkinson, a widely respected naval officer who set the stage for many of the protocols of today's Nuclear Navy of the US, and who had a storied career during military service and afterwards.

Sharing a name with Captain Nemo's fictional submarine in Jules Verne's classic 1870 science fiction novel Twenty Thousand Leagues Under the Sea and the that served with distinction in World War II, the new nuclear-powered Nautilus was authorized in 1951. Construction began in 1952, and the boat was launched in January 1954, sponsored by Mamie Eisenhower, First Lady of the United States, wife of 34th President Dwight D. Eisenhower; it was commissioned the following September into the United States Navy. Nautilus was delivered to the Navy in 1955.

Because her nuclear propulsion allowed her to remain submerged far longer than diesel-electric submarines, she broke many records in her first years of operation and traveled to locations previously beyond the limits of submarines. In operation, she revealed a number of limitations in her design and construction. This information was used to improve subsequent submarines.

Nautilus was decommissioned in 1980 and designated a National Historic Landmark in 1982. The submarine has been preserved as a museum ship at the Submarine Force Library and Museum in Groton, Connecticut, where the vessel receives around 250,000 visitors per year.

The conceptual design of the first nuclear submarine began in March 1950 as project SCB 64. In July 1951, the United States Congress authorized the construction of a nuclear-powered submarine for the U.S. Navy, which was planned and personally supervised by Captain (later Admiral) Hyman G. Rickover, USN, known as the "Father of the Nuclear Navy." On 12 December 1951, the US Department of the Navy announced that the submarine would be called Nautilus, the fourth U.S. Navy vessel officially so named. The boat carried the hull number SSN-571. She benefited from the Greater Underwater Propulsion Power (GUPPY) improvements to the American Gato-, Balao-, and Tench-class submarines.

Nautilus's keel was laid at General Dynamics' Electric Boat Division in Groton, Connecticut, by Harry S. Truman on 14 June 1952. She was christened on 21 January 1954 and launched into the Thames River, sponsored by Mamie Eisenhower. Nautilus was commissioned on 30 September 1954, under the command of Commander Eugene P. Wilkinson, USN.

Nautilus was powered by the Submarine Thermal Reactor (STR), later redesignated the S2W reactor, a pressurized water reactor produced for the US Navy by Westinghouse Electric Corporation. Bettis Atomic Power Laboratory, operated by Westinghouse, developed the basic reactor plant design used in Nautilus after being given the assignment on 31 December 1947 to design a nuclear power plant for a submarine. Nuclear power had a crucial advantage in submarine propulsion because it is a zero-emission process that consumes no air. This design is the basis for nearly all of the US nuclear-powered submarine and surface combat ships, and was adapted by other countries for naval nuclear propulsion. The first actual prototype (for Nautilus) was constructed and tested by the Argonne National Laboratory in 1953 at S1W at the Naval Reactors Facility, part of the National Reactor Testing Station in Idaho.

Nautilus' ship's patch was designed by The Walt Disney Company, and her wardroom currently displays a set of tableware made of zirconium, as the nuclear fuel cladding was partly made of zirconium.

"Underway on nuclear power"

Following her commissioning, Nautilus remained dockside for further construction and testing. On the morning of 17 January 1955, at 11 am EST, Nautilus' first Commanding Officer, Commander Eugene P. Wilkinson, ordered all lines cast off and signaled the memorable and historic message, "Underway on nuclear power." On 10 May, she headed south for shakedown. Submerged throughout, she traveled 1,100 nmi (2,000 km; 1,300 mi) from New London to San Juan, Puerto Rico and covered 1,200 nmi (2,200 km; 1,400 mi) in less than ninety hours. At the time, this was the longest submerged cruise by a submarine and at the highest sustained speed (for at least one hour) ever recorded.

From 1955 to 1957, Nautilus continued to be used to investigate the effects of increased submerged speeds and endurance. These improvements rendered the progress made in anti-submarine warfare during World War II virtually obsolete. Radar and anti-submarine aircraft, which had proved crucial in defeating submarines during the war, proved ineffective against a vessel able to move quickly out of an area, change depth quickly and stay submerged for very long periods.

On 4 February 1957, Nautilus logged her 60,000th nautical mile (110,000 km; 69,000 mi), matching the endurance of her namesake, the fictional Nautilus described in Jules Verne's novel Twenty Thousand Leagues Under The Sea. In May, she departed for the Pacific Coast to participate in coastal exercises and the fleet exercise, operation "Home Run," which acquainted units of the Pacific Fleet with the capabilities of nuclear submarines.

Nautilus returned to New London, Connecticut, on 21 July and departed again on 19 August for her first voyage of 1,200 nmi (2,200 km; 1,400 mi) under the polar pack ice. Thereafter, she headed for the Eastern Atlantic to participate in NATO exercises and conduct a tour of various British and French ports where she was inspected by defense personnel of those countries. She arrived back at New London on 28 October, underwent upkeep, and then conducted coastal operations until the spring.

Operation Sunshine - under the North Pole

In response to the nuclear ICBM threat posed by Sputnik, President Eisenhower ordered the U.S. Navy to attempt a submarine transit of the North Pole to gain credibility for the soon-to-come SLBM weapons system. On 25 April 1958, Nautilus was underway again for the West Coast, now commanded by Commander William R. Anderson, USN. Stopping at San Diego, San Francisco, and Seattle, she began her history-making polar transit, " Operation Sunshine", as she departed the latter port on 9 June. On 19 June, she entered the Chukchi Sea, but was turned back by deep drift ice in those shallow waters. On 28 June, she arrived at Pearl Harbor to await better ice conditions.

By 23 July, her wait was over, and she set a course northward. She submerged in the Barrow Sea Valley on 1 August and on 3 August, at 2315 hrs. EDT she became the first watercraft to reach the geographic North Pole. The ability to navigate at extreme latitudes without surfacing was enabled by the technology of the North American Aviation N6A-1 Inertial Navigation System, a naval modification of the N6A used in the Navaho cruise missile; it had been installed on Nautilus and Skate after initial sea trials on USS Compass Island in 1957. From the North Pole, she continued and after 96 hours and 1,590 nmi (2,940 km; 1,830 mi) under the ice, surfaced northeast of Greenland, having completed the first successful submerged voyage around the North Pole. The technical details of this mission were planned by scientists from the Naval Electronics Laboratory including Dr. Waldo Lyon who accompanied Nautilus as chief scientist and ice pilot.

Navigation beneath the arctic ice sheet was difficult. Above 85°N both magnetic compasses and normal gyrocompasses become inaccurate. A special gyrocompass built by Sperry Rand was installed shortly before the journey. There was a risk that the submarine would become disoriented beneath the ice and that the crew would have to play "longitude roulette". Commander Anderson had considered using torpedoes to blow a hole in the ice if the submarine needed to surface.

The most difficult part of the journey was in the Bering Strait. The ice extended as much as 60 ft (18 m) below sea level. During the initial attempt to go through the Bering Strait, there was insufficient room between the ice and the sea bottom. During the second, successful attempt to pass through the Bering passage, the submarine passed through a known channel close to Alaska (this was not the first choice, as the submarine wanted to avoid detection).

The trip beneath the ice cap was an important boost for America as the Soviets had recently launched Sputnik, but had no nuclear submarine of their own. During the address announcing the journey, the president mentioned that one day nuclear cargo submarines might use that route for trade.

As Nautilus proceeded south from Greenland, a helicopter airlifted Commander Anderson to connect with transport to Washington, D.C. At a White House ceremony on 8 August, President Eisenhower presented him with the Legion of Merit and announced that the crew had earned a Presidential Unit Citation.

At her next port of call, the Isle of Portland, England, she received the Unit Citation, the first ever issued in peace time, from American Ambassador JH Whitney, and then crossed the Atlantic reaching New London, Connecticut, on 29 October. For the remainder of the year, Nautilus operated from her home port of New London.

Following fleet exercises in early 1959, Nautilus entered the Portsmouth Naval Shipyard in Kittery, Maine, for her first complete overhaul (28 May 1959 - 15 August 1960). Overhaul was followed by refresher training and on 24 October she departed New London for her first deployment with the Sixth Fleet in the Mediterranean Sea, returning to her home-port on 16 December.

Nautilus spent most of her career assigned to Submarine Squadron 10 (SUBRON 10) at State Pier in New London, Connecticut. Nautilus and other submarines in the squadron made their home tied up alongside the tender, where they received preventive maintenance, and if necessary, repairs, from the well-equipped submarine tender USS Fulton (AS-11) and her crew of machinists, millwrights, and other craftsmen.

Nautilus operated in the Atlantic, conducting evaluation tests for ASW improvements, participating in NATO exercises, and during October 1962, in the naval quarantine of Cuba, until she headed east again for a two-month Mediterranean tour in August 1963. On her return she joined in fleet exercises until entering the Portsmouth Naval Shipyard for her second overhaul on 17 January 1964.

On 2 May 1966, Nautilus returned to her homeport to resume operations with the Atlantic Fleet, and at some point during that month, logged her 300,000th nautical mile (560,000 km; 350,000 mi) underway. For the next year and a quarter she conducted special operations for ComSubLant and then in August 1967, returned to Portsmouth, for another year's stay. During an exercise in 1966 she collided with the aircraft carrier USS Essex on 10 November, while at shallow depth. Following repairs in Portsmouth she conducted exercises off the southeastern seaboard. She returned to New London in December 1968 and operated as a unit of Submarine Squadron 10 for most of the remainder of her career.

On 9 April 1979, Nautilus set out from Groton, Connecticut on her final voyage under the command of Richard A. Riddell. She reached Mare Island Naval Shipyard of Vallejo, California on 26 May 1979, her last day underway. She was decommissioned and stricken from the Naval Vessel Register on 3 March 1980.

Toward the end of her service, the hull and sail of Nautilus vibrated sufficiently that sonar became ineffective at more than 4 kn (7.4 km/h; 4.6 mph) speed. As noise generation is extremely undesirable in submarines, this made the vessel vulnerable to sonar detection. Lessons learned from this problem were applied to later nuclear submarines.

For outstanding achievement in completing the first voyage in history across the top of the world, by cruising under the Arctic ice cap from the Bering Strait to the Greenland Sea.

During the period 22 July 1958 to 5 August 1958, USS Nautilus, the world's first nuclear powered ship, added to her list of historic achievements by crossing the Arctic Ocean from the Bering Sea to the Greenland Sea, passing submerged beneath the geographic North Pole. This voyage opens the possibility of a new commercial seaway, a Northwest Passage, between the major oceans of the world. Nuclear-powered cargo submarines may, in the future, use this route to the advantage of world trade.

The skill, professional competency and courage of the officers and crew of Nautilus were in keeping with the highest traditions of the Armed Forces of the United States and the pioneering spirit which has always characterized the country.

To commemorate the first submerged voyage under the North Pole, all Nautilus crewmembers who made the voyage may wear a Presidential Unit Citation ribbon with a special clasp in the form of a gold block letter N (image above).

Nautilus was designated a National Historic Landmark by the United States Secretary of the Interior on 20 May 1982.

She was named as the official state ship of Connecticut in 1983. Following an extensive conversion at Mare Island Naval Shipyard, Nautilus was towed back to Groton, under the command of Captain John Almon, arriving on 6 July 1985. On 11 April 1986, Nautilus opened to the public as part of the Submarine Force Library and Museum.

Nautilus now serves as a museum of submarine history operated by the Naval History and Heritage Command. The ship underwent a five-month preservation in 2002 at Electric Boat, at a cost of approximately $4.7 million. Nautilus attracts some 250,000 visitors annually to her present berth near Naval Submarine Base New London.

Nautilus celebrated the 50th anniversary of her commissioning on 30 September 2004 with a ceremony that included a speech from Vice Admiral Eugene P. Wilkinson, her first Commanding Officer, and a designation of the ship as an American Nuclear Society National Nuclear Landmark.

Visitors may tour the forward two compartments, with guidance from an automated system. Despite similar alterations to exhibit the engineering spaces, tours aft of the control room are not permitted due to safety and security concerns.

In March of 2022, Nautilus began a restoration process that was expected to last 6 to 8 months. Included in the work: blasting and painting of the hull, installation of new top decks, as well as upgraded interior lighting and electrical. The restoration was completed at a cost of US$36 million.

Friedman, Norman (1994). U.S. Submarines Since 1945: An Illustrated Design History. Annapolis, Maryland: United States Naval Institute. ISBN 1-55750-260-9.

Hewlett, Richard; Duncan, Francis (1974). Nuclear Navy 1946-1962. Chicago, Illinois: University of Chicago Press. ISBN 0-226-32219-5.

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Class overview Builders General Dynamics Operators United States Navy Preceded by Tang-class submarine Succeeded by USS Seawolf Built 1952 In commission 1954-1980 History United States Name Nautilus Namesake Captain Nemo's " Nautilus" submarine[1] Awarded 2 August 1951 Builder General Dynamics Laid down 14 June 1952 Launched 21 January 1954 Sponsored

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Submarine USS Nautilus was commission on September 30 1954

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Submarine USS Nautilus was commission on September 30 1954

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Στην ελληνική μυθολογία η Πενθεσίλεια ήταν βασίλισσα των Αμαζόνων.

Ήταν κόρη του θεού του πολέμου Άρη και της Οτρήρης. Η βασιλεία της ανάγεται στην εποχή του Τρωικού Πολέμου, ενώ στην (υποτίθεται προγενέστερη) εποχή του Ηρακλέους βασίλισσα των Αμαζόνων ήταν η Ιππολύτη. Μετά τον θάνατο του Έκτορα στον Τρωικό Πόλεμο, η Πενθεσίλεια ήρθε "από τον αλαργινό Πόντο" να βοηθήσει τους Τρώες επικεφαλής στρατού από Αμαζόνες. Σύμφωνα με κάποια εκδοχή είχε αναγκασθεί να εγκαταλείψει τη χώρα της μετά από κάποιο φόνο που διέπραξε άθελά της, ή ήθελε να εξαγοράσει το κρίμα. Συγκεκριμένα, είχε σκοτώσει κατά λάθος την αδελφή της στο κυνήγι κι έλπιζε βοηθώντας τους Τρώες, που τους προστάτευε η θεά Άρτεμη, προστάτιδα και του κυνηγιού, ότι θα τη συγχωρούσε η θεά.

Ο βασιλιάς της Τροίας, ο Πρίαμος, δέχθηκε την Πενθεσίλεια σα να ήταν πραγματική κόρη του και ετοίμασε πλούσιο τραπέζι γι' αυτή. Η Πενθεσίλεια και οι Αμαζόνες της διακρίθηκαν στη μάχη. Κυνήγησαν τον εχθρό μέχρι τα πλοία του, αλλά τελικώς η Πενθεσίλεια τραυματίσθηκε θανάσιμα από τον Αχιλλέα.

Ο θάνατος της Πενθεσίλειας περιγράφεται με λεπτομέρεια, όχι στην Ιλιάδα, αλλά στις "Ηρωίδες" του Οβιδίου και την του Βιργιλίου: Προς το τέλος του Τρωικού Πολέμου ο Αχιλλέας βρέθηκε αντιμέτωπος με την Πενθεσίλεια, που πολεμούσε φορώντας πολεμική μάσκα και του έριξε το κοντάρι της, το οποίο έγινε κομμάτια μόλις χτύπησε στην ασπίδα του Αχιλλέα. Η Πενθεσίλεια έριξε και δεύτερο κοντάρι, αλλά ούτε και τότε τον πλήγωσε. Ο Αχιλλέας τότε κατόρθωσε να την τραυματίσει θανάσιμα στο στήθος, οπότε πήγε κοντά της και έβγαλε τη μάσκα της. Η συγκίνηση του ήρωα ήταν τότε καταφανής σε όλους. Η ομορφιά της Πενθεσίλειας τον γέμισε μελαγχολία και όσοι ήταν παρόντες δεν είχαν καμιά αμφιβολία ότι ο Αχιλλέας είχε εκείνη τη στιγμή ερωτευθεί τη γυναίκα που σε λίγο θα πέθαινε. Αλλά ο Θερσίτης, ακόμα και την τραγική αυτή ώρα, αισθάνθηκε την ανάγκη να περιγελάσει τον Αχιλλέα, έμπηξε μάλιστα και το κοντάρι του μέσα στο μάτι της Πενθεσίλειας. Τότε ο ήρωας, έξαλλος από θυμό, σηκώθηκε και τον σκότωσε με γροθιές στο στομάχι, "εν βρασμώ ψυχής". Στη συνέχεια, σήκωσε απαλά τη βασίλισσα και την έβγαλε από το πεδίο της μάχης. Το σώμα της, μαζί με τα πτώματα 12 άλλων Αμαζόνων, τα παρέδωσαν με ολόκληρο τον οπλισμό τους στους Τρώες. Κι αυτοί τα έκαψαν και έθαψαν τις στάχτες με όλες τις τιμές.

Η Πενθεσίλεια απεικονίζεται σε κύλικα του 5ου αιώνα π.Χ. και αρκετά άλλα αγγεία. Το θέμα ζωγράφισε τόσες φορές ένας ανώνυμος αγγειογράφος του 6ου αιώνα π.Χ., ώστε ο Άντολφ Φουρτβένγκλερ τον ονόμασε συμβατικά " Ζωγράφο της Πενθεσίλειας ".

Ο αστεροειδής 271 Πενθεσίλεια (271 Penthesilea), που ανακαλύφθηκε το 1887, πήρε το όνομά του από τη μυθική αυτή Αμαζόνα. Αρκετά επίσης είναι τα λογοτεχνικά έργα που βασίσθηκαν στον μύθο της, με θεωρούμενο σημαντικότερο την τραγωδία "Πενθεσίλεια" του Χάινριχ φον Κλάιστ (1808), πάνω στην οποία βασίζεται και η ομώνυμη μονόπρακτη όπερα του Ελβετού συνθέτη Othmar Schoeck (1927).

Emmy Patsi-Garin: "Επίτομο λεξικό Ελληνικής Μυθολογίας", εκδ. οίκος Χάρη Πάτση, Αθήνα 1969

Το αντίστοιχο άρθρο της αγγλόγλωσσης Wikipedia.

Το ποίημα Πενθεσίλεια σε αγγλικά και ελληνικά (Ρόμπερτ Γκρέιβς / Robert Graves | μετάφραση: Σπύρος Δόικας)

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Πενθεσίλεια - Βικιπαίδεια

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Στην ελληνική μυθολογία η Πενθεσίλεια ήταν βασίλισσα των Αμαζόνων. Ήταν κόρη του θεού του πολέμου Άρη και της Οτρήρης. Η βασιλεία της ανάγεται στην εποχή του Τρωικού Πολέμου, ενώ στην (υποτίθεται προγενέστερη) εποχή του Ηρακλέους βασίλισσα των Αμαζόνων ήταν η Ιππολύτη.

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From Wikipedia, the free encyclopedia

Inkan aarre ( Finnish for "The treasure of the Inca") is a 2005 Finnish board game, designed by Kari Mannerla as a direct sequel to his 1951 board game Afrikan tähti.

Inkan aarre is mostly similar to Afrikan tähti. Players take turns to move around a board of interconnected cities, picking up tokens in search for the famous treasure of the Inca, a golden sun god statue.

The board represents the continent of South America, and the currency used is the Mexican peso. All players start from Rio de Janeiro, Brazil. Once the treasure of the Inca has been found, the first player to take either the treasure or a sun icon to Machu Picchu, Peru, wins the game.

The game now has one starting location (Rio de Janeiro) and one ending location (Machu Picchu); these are not interchangeable.

The Native American guide is a new token.

The rule that players can travel on the sea for free if they have no money has been made official.

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From Wikipedia, the free encyclopedia Inkan aarre ( Finnish for "The treasure of the Inca") is a 2005 Finnish board game, designed by Kari Mannerla as a direct sequel to his 1951 board game Afrikan tähti . Inkan aarre is mostly similar to Afrikan tähti.

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Praying Altar for Saint Rob, Patron Saint of Easter Egg Hunters and Lost Time

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Praying Altar for Saint Rob, Patron Saint of Easter Egg Hunters and Lost Time

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Pray to SR for guidance on these Easter Eggs hunts

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L 24 239 MH19 64PLC 012971
PROCTER & GAMBLE HYGIENE AND HEALTH CARE LIMITED

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Effective potential - Wikipedia

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From Wikipedia, the free encyclopedia

The effective potential (also known as effective potential energy) combines multiple, perhaps opposing, effects into a single potential. In its basic form, it is the sum of the 'opposing' centrifugal potential energy with the potential energy of a dynamical system. It may be used to determine the orbits of planets (both Newtonian and relativistic) and to perform semi-classical atomic calculations, and often allows problems to be reduced to fewer dimensions.

The basic form of potential is defined as:

where

L is the angular momentum

r is the distance between the two masses

μ is the reduced mass of the two bodies (approximately equal to the mass of the orbiting body if one mass is much larger than the other); and

U(r) is the general form of the potential.

The effective force, then, is the negative gradient of the effective potential:

where denotes a unit vector in the radial direction.

There are many useful features of the effective potential, such as

To find the radius of a circular orbit, simply minimize the effective potential with respect to , or equivalently set the net force to zero and then solve for :

After solving for , plug this back into to find the maximum value of the effective potential .

A circular orbit may be either stable or unstable. If it is unstable, a small perturbation could destabilize the orbit, but a stable orbit would return to equilibrium. To determine the stability of a circular orbit, determine the concavity of the effective potential. If the concavity is positive, the orbit is stable:

The frequency of small oscillations, using basic Hamiltonian analysis, is

where the double prime indicates the second derivative of the effective potential with respect to and it is evaluated at a minimum.

Consider a particle of mass m orbiting a much heavier object of mass M. Assume Newtonian mechanics, which is both classical and non-relativistic. The conservation of energy and angular momentum give two constants E and L, which have values

when the motion of the larger mass is negligible. In these expressions,

Only two variables are needed, since the motion occurs in a plane. Substituting the second expression into the first and rearranging gives

where

is the effective potential. The original two-variable problem has been reduced to a one-variable problem. For many applications the effective potential can be treated exactly like the potential energy of a one-dimensional system: for instance, an energy diagram using the effective potential determines turning points and locations of stable and unstable equilibria. A similar method may be used in other applications, for instance determining orbits in a general relativistic Schwarzschild metric.

Effective potentials are widely used in various condensed matter subfields, e.g. the Gauss-core potential (Likos 2002, Baeurle 2004) and the screened Coulomb potential (Likos 2001).

Baeurle, S.A.; Kroener J. (2004). "Modeling Effective Interactions of Micellar Aggregates of Ionic Surfactants with the Gauss-Core Potential". J. Math. Chem. 36 (4): 409-421. doi:10.1023/B:JOMC.0000044526.22457.bb.

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From Wikipedia, the free encyclopedia The effective potential (also known as effective potential energy) combines multiple, perhaps opposing, effects into a single potential. In its basic form, it is the sum of the 'opposing' centrifugal potential energy with the potential energy of a dynamical system.