# data[].attributes.attachment_link.readable_text
Who Was Isaac Newton?

Isaac Newton was a physicist and mathematician who developed the principles of modern physics, including the laws of motion and is credited as one of the great minds of the 17th-century Scientific Revolution.

In 1687, he published his most acclaimed work, Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), which has been called the single most influential book on physics. In 1705, he was knighted by Queen Anne of England, making him Sir Isaac Newton.

Early Life and Family

Newton was born on January 4, 1643, in Woolsthorpe, Lincolnshire, England. Using the "old" Julian calendar, Newton's birth date is sometimes displayed as December 25, 1642.

Newton was the only son of a prosperous local farmer, also named Isaac, who died three months before he was born. A premature baby born tiny and weak, Newton was not expected to survive.

When he was 3 years old, his mother, Hannah Ayscough Newton, remarried a well-to-do minister, Barnabas Smith, and went to live with him, leaving young Newton with his maternal grandmother.

The experience left an indelible imprint on Newton, later manifesting itself as an acute sense of insecurity. He anxiously obsessed over his published work, defending its merits with irrational behavior.

At age 12, Newton was reunited with his mother after her second husband died. She brought along her three small children from her second marriage.

Isaac Newton's Education

Newton was enrolled at the King's School in Grantham, a town in Lincolnshire, where he lodged with a local apothecary and was introduced to the fascinating world of chemistry.

His mother pulled him out of school at age 12. Her plan was to make him a farmer and have him tend the farm. Newton failed miserably, as he found farming monotonous. Newton was soon sent back to King's School to finish his basic education.

Perhaps sensing the young man's innate intellectual abilities, his uncle, a graduate of the University of Cambridge's Trinity College, persuaded Newton's mother to have him enter the university. Newton enrolled in a program similar to a work-study in 1661, and subsequently waited on tables and took care of wealthier students' rooms.

Scientific Revolution

When Newton arrived at Cambridge, the Scientific Revolution of the 17th century was already in full force. The heliocentric view of the universe-theorized by astronomers Nicolaus Copernicus and Johannes Kepler, and later refined by Galileo -was well known in most European academic circles.

Philosopher René Descartes had begun to formulate a new concept of nature as an intricate, impersonal and inert machine. Yet, like most universities in Europe, Cambridge was steeped in Aristotelian philosophy and a view of nature resting on a geocentric view of the universe, dealing with nature in qualitative rather than quantitative terms.

During his first three years at Cambridge, Newton was taught the standard curriculum but was fascinated with the more advanced science. All his spare time was spent reading from the modern philosophers. The result was a less-than-stellar performance, but one that is understandable, given his dual course of study.

It was during this time that Newton kept a second set of notes, entitled "Quaestiones Quaedam Philosophicae" ("Certain Philosophical Questions"). The "Quaestiones" reveal that Newton had discovered the new concept of nature that provided the framework for the Scientific Revolution. Though Newton graduated without honors or distinctions, his efforts won him the title of scholar and four years of financial support for future education.

In 1665, the bubonic plague that was ravaging Europe had come to Cambridge, forcing the university to close. After a two-year hiatus, Newton returned to Cambridge in 1667 and was elected a minor fellow at Trinity College, as he was still not considered a standout scholar.

In the ensuing years, his fortune improved. Newton received his Master of Arts degree in 1669, before he was 27. During this time, he came across Nicholas Mercator's published book on methods for dealing with infinite series.

Newton quickly wrote a treatise, De Analysi, expounding his own wider-ranging results. He shared this with friend and mentor Isaac Barrow, but didn't include his name as author.

In June 1669, Barrow shared the unaccredited manuscript with British mathematician John Collins. In August 1669, Barrow identified its author to Collins as "Mr. Newton ... very young ... but of an extraordinary genius and proficiency in these things."

Newton's work was brought to the attention of the mathematics community for the first time. Shortly afterward, Barrow resigned his Lucasian professorship at Cambridge, and Newton assumed the chair.

Isaac Newton's Discoveries

Newton made discoveries in optics, motion and mathematics. Newton theorized that white light was a composite of all colors of the spectrum, and that light was composed of particles.

His momentous book on physics, Principia, contains information on nearly all of the essential concepts of physics except energy, ultimately helping him to explain the laws of motion and the theory of gravity. Along with mathematician Gottfried Wilhelm von Leibniz, Newton is credited for developing essential theories of calculus.

Isaac Newton Inventions

Newton's first major public scientific achievement was designing and constructing a reflecting telescope in 1668. As a professor at Cambridge, Newton was required to deliver an annual course of lectures and chose optics as his initial topic. He used his telescope to study optics and help prove his theory of light and color.

The Royal Society asked for a demonstration of his reflecting telescope in 1671, and the organization's interest encouraged Newton to publish his notes on light, optics and color in 1672. These notes were later published as part of Newton's Opticks: Or, A treatise of the Reflections, Refractions, Inflections and Colours of Light.

Photo: Hulton Archive/Getty Images

The Apple Myth

Between 1665 and 1667, Newton returned home from Trinity College to pursue his private study, as school was closed due to the Great Plague. Legend has it that, at this time, Newton experienced his famous inspiration of gravity with the falling apple. According to this common myth, Newton was sitting under an apple tree when a fruit fell and hit him on the head, inspiring him to suddenly come up with the theory of gravity.

While there is no evidence that the apple actually hit Newton on the head, he did see an apple fall from a tree, leading him to wonder why it fell straight down and not at an angle. Consequently, he began exploring the theories of motion and gravity.

It was during this 18-month hiatus as a student that Newton conceived many of his most important insights-including the method of infinitesimal calculus, the foundations for his theory of light and color, and the laws of planetary motion-that eventually led to the publication of his physics book Principia and his theory of gravity.

Isaac Newton's Laws of Motion

In 1687, following 18 months of intense and effectively nonstop work, Newton published Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), most often known as Principia.

Principia is said to be the single most influential book on physics and possibly all of science. Its publication immediately raised Newton to international prominence.

Principia offers an exact quantitative description of bodies in motion, with three basic but important laws of motion:

First Law

A stationary body will stay stationary unless an external force is applied to it.

Second Law

Force is equal to mass times acceleration, and a change in motion (i.e., change in speed) is proportional to the force applied.

Third Law

For every action, there is an equal and opposite reaction.

Newton and the Theory of Gravity

Newton's three basic laws of motion outlined in Principia helped him arrive at his theory of gravity. Newton's law of universal gravitation states that two objects attract each other with a force of gravitational attraction that's proportional to their masses and inversely proportional to the square of the distance between their centers.

These laws helped explain not only elliptical planetary orbits but nearly every other motion in the universe: how the planets are kept in orbit by the pull of the sun's gravity; how the moon revolves around Earth and the moons of Jupiter revolve around it; and how comets revolve in elliptical orbits around the sun.

They also allowed him to calculate the mass of each planet, calculate the flattening of the Earth at the poles and the bulge at the equator, and how the gravitational pull of the sun and moon create the Earth's tides. In Newton's account, gravity kept the universe balanced, made it work, and brought heaven and Earth together in one great equation.

DOWNLOAD BIOGRAPHY'S ISAAC NEWTON FACT CARD

Isaac Newton & Robert Hooke

Not everyone at the Royal Academy was enthusiastic about Newton's discoveries in optics and 1672 publication of Opticks: Or, A treatise of the Reflections, Refractions, Inflections and Colours of Light. Among the dissenters was Robert Hooke, one of the original members of the Royal Academy and a scientist who was accomplished in a number of areas, including mechanics and optics.

While Newton theorized that light was composed of particles, Hooke believed it was composed of waves. Hooke quickly condemned Newton's paper in condescending terms, and attacked Newton's methodology and conclusions.

Hooke was not the only one to question Newton's work in optics. Renowned Dutch scientist Christiaan Huygens and a number of French Jesuits also raised objections. But because of Hooke's association with the Royal Society and his own work in optics, his criticism stung Newton the worst.

Unable to handle the critique, he went into a rage-a reaction to criticism that was to continue throughout his life. Newton denied Hooke's charge that his theories had any shortcomings and argued the importance of his discoveries to all of science.

In the ensuing months, the exchange between the two men grew more acrimonious, and soon Newton threatened to quit the Royal Society altogether. He remained only when several other members assured him that the Fellows held him in high esteem.

The rivalry between Newton and Hooke would continue for several years thereafter. Then, in 1678, Newton suffered a complete nervous breakdown and the correspondence abruptly ended. The death of his mother the following year caused him to become even more isolated, and for six years he withdrew from intellectual exchange except when others initiated correspondence, which he always kept short.

During his hiatus from public life, Newton returned to his study of gravitation and its effects on the orbits of planets. Ironically, the impetus that put Newton on the right direction in this study came from Robert Hooke.

In a 1679 letter of general correspondence to Royal Society members for contributions, Hooke wrote to Newton and brought up the question of planetary motion, suggesting that a formula involving the inverse squares might explain the attraction between planets and the shape of their orbits.

Subsequent exchanges transpired before Newton quickly broke off the correspondence once again. But Hooke's idea was soon incorporated into Newton's work on planetary motion, and from his notes it appears he had quickly drawn his own conclusions by 1680, though he kept his discoveries to himself.

In early 1684, in a conversation with fellow Royal Society members Christopher Wren and Edmond Halley, Hooke made his case on the proof for planetary motion. Both Wren and Halley thought he was on to something, but pointed out that a mathematical demonstration was needed.

In August 1684, Halley traveled to Cambridge to visit with Newton, who was coming out of his seclusion. Halley idly asked him what shape the orbit of a planet would take if its attraction to the sun followed the inverse square of the distance between them (Hooke's theory).

Newton knew the answer, due to his concentrated work for the past six years, and replied, "An ellipse." Newton claimed to have solved the problem some 18 years prior, during his hiatus from Cambridge and the plague, but he was unable to find his notes. Halley persuaded him to work out the problem mathematically and offered to pay all costs so that the ideas might be published, which it was, in Newton's Principia.

Upon the publication of the first edition of Principia in 1687, Robert Hooke immediately accused Newton of plagiarism, claiming that he had discovered the theory of inverse squares and that Newton had stolen his work. The charge was unfounded, as most scientists knew, for Hooke had only theorized on the idea and had never brought it to any level of proof.

Newton, however, was furious and strongly defended his discoveries. He withdrew all references to Hooke in his notes and threatened to withdraw from publishing the subsequent edition of Principia altogether.

Halley, who had invested much of himself in Newton's work, tried to make peace between the two men. While Newton begrudgingly agreed to insert a joint acknowledgment of Hooke's work (shared with Wren and Halley) in his discussion of the law of inverse squares, it did nothing to placate Hooke.

As the years went on, Hooke's life began to unravel. His beloved niece and companion died the same year that Principia was published, in 1687. As Newton's reputation and fame grew, Hooke's declined, causing him to become even more bitter and loathsome toward his rival.

To the very end, Hooke took every opportunity he could to offend Newton. Knowing that his rival would soon be elected president of the Royal Society, Hooke refused to retire until the year of his death, in 1703.

Newton and Alchemy

Following the publication of Principia, Newton was ready for a new direction in life. He no longer found contentment in his position at Cambridge and was becoming more involved in other issues.

He helped lead the resistance to King James II's attempts to reinstitute Catholic teaching at Cambridge, and in 1689 he was elected to represent Cambridge in Parliament.

While in London, Newton acquainted himself with a broader group of intellectuals and became acquainted with political philosopher John Locke. Though many of the scientists on the continent continued to teach the mechanical world according to Aristotle, a young generation of British scientists became captivated with Newton's new view of the physical world and recognized him as their leader.

One of these admirers was Nicolas Fatio de Duillier, a Swiss mathematician whom Newton befriended while in London.

However, within a few years, Newton fell into another nervous breakdown in 1693. The cause is open to speculation: his disappointment over not being appointed to a higher position by England's new monarchs, William III and Mary II, or the subsequent loss of his friendship with Duillier; exhaustion from being overworked; or perhaps chronic mercury poisoning after decades of alchemical research.

It's difficult to know the exact cause, but evidence suggests that letters written by Newton to several of his London acquaintances and friends, including Duillier, seemed deranged and paranoiac, and accused them of betrayal and conspiracy.

Oddly enough, Newton recovered quickly, wrote letters of apology to friends, and was back to work within a few months. He emerged with all his intellectual facilities intact, but seemed to have lost interest in scientific problems and now favored pursuing prophecy and scripture and the study of alchemy.

While some might see this as work beneath the man who had revolutionized science, it might be more properly attributed to Newton responding to the issues of the time in turbulent 17th century Britain.

Many intellectuals were grappling with the meaning of many different subjects, not least of which were religion, politics and the very purpose of life. Modern science was still so new that no one knew for sure how it measured up against older philosophies.

Gold Standard

In 1696, Newton was able to attain the governmental position he had long sought: warden of the Mint; after acquiring this new title, he permanently moved to London and lived with his niece, Catherine Barton.

Barton was the mistress of Lord Halifax, a high-ranking government official who was instrumental in having Newton promoted, in 1699, to master of the Mint-a position that he would hold until his death.

Not wanting it to be considered a mere honorary position, Newton approached the job in earnest, reforming the currency and severely punishing counterfeiters. As master of the Mint, Newton moved the British currency, the pound sterling, from the silver to the gold standard.

The Royal Society

In 1703, Newton was elected president of the Royal Society upon Robert Hooke's death. However, Newton never seemed to understand the notion of science as a cooperative venture, and his ambition and fierce defense of his own discoveries continued to lead him from one conflict to another with other scientists.

By most accounts, Newton's tenure at the society was tyrannical and autocratic; he was able to control the lives and careers of younger scientists with absolute power.

In 1705, in a controversy that had been brewing for several years, German mathematician Gottfried Leibniz publicly accused Newton of plagiarizing his research, claiming he had discovered infinitesimal calculus several years before the publication of Principia.

In 1712, the Royal Society appointed a committee to investigate the matter. Of course, since Newton was president of the society, he was able to appoint the committee's members and oversee its investigation. Not surprisingly, the committee concluded Newton's priority over the discovery.

That same year, in another of Newton's more flagrant episodes of tyranny, he published without permission the notes of astronomer John Flamsteed. It seems the astronomer had collected a massive body of data from his years at the Royal Observatory at Greenwich, England.

Newton had requested a large volume of Flamsteed's notes for his revisions to Principia. Annoyed when Flamsteed wouldn't provide him with more information as quickly as he wanted it, Newton used his influence as president of the Royal Society to be named the chairman of the body of "visitors" responsible for the Royal Observatory.

He then tried to force the immediate publication of Flamsteed's catalogue of the stars, as well as all of Flamsteed's notes, edited and unedited. To add insult to injury, Newton arranged for Flamsteed's mortal enemy, Edmund Halley, to prepare the notes for press.

Flamsteed was finally able to get a court order forcing Newton to cease his plans for publication and return the notes-one of the few times that Newton was bested by one of his rivals.

Final Years

Toward the end of this life, Newton lived at Cranbury Park, near Winchester, England, with his niece, Catherine (Barton) Conduitt, and her husband, John Conduitt.

By this time, Newton had become one of the most famous men in Europe. His scientific discoveries were unchallenged. He also had become wealthy, investing his sizable income wisely and bestowing sizable gifts to charity.

Despite his fame, Newton's life was far from perfect: He never married or made many friends, and in his later years, a combination of pride, insecurity and side trips on peculiar scientific inquiries led even some of his few friends to worry about his mental stability.

Death

By the time he reached 80 years of age, Newton was experiencing digestion problems and had to drastically change his diet and mobility.

In March 1727, Newton experienced severe pain in his abdomen and blacked out, never to regain consciousness. He died the next day, on March 31, 1727, at the age of 84.

Legacy

Newton's fame grew even more after his death, as many of his contemporaries proclaimed him the greatest genius who ever lived. Maybe a slight exaggeration, but his discoveries had a large impact on Western thought, leading to comparisons to the likes of Plato, Aristotle and Galileo.

Although his discoveries were among many made during the Scientific Revolution, Newton's universal principles of gravity found no parallels in science at the time.

Of course, Newton was proven wrong on some of his key assumptions. In the 20th century, Albert Einstein would overturn Newton's concept of the universe, stating that space, distance and motion were not absolute but relative and that the universe was more fantastic than Newton had ever conceived.

Newton might not have been surprised: In his later life, when asked for an assessment of his achievements, he replied, "I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself now and then in finding a smoother pebble or prettier shell than ordinary, while the great ocean of truth lay all undiscovered before me."

# data[].attributes.attachment_link.description
Isaac Newton was a physicist and mathematician who developed the principles of modern physics, including the laws of motion and is credited as one of the great minds of the 17th-century Scientific Revolution. In 1687, he published his most acclaimed work, Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), which has been called the single most influential book on physics.

# data[].attributes.body
He lived in London, England, United Kingdom.

He made the first reflecting telescope and then wrote a book called Principia that said:

1: The Gravity: He discovered a apple falling down.

2: Elliptical orbit : He said that it is important to have elliptical Orbit.

# data[].attributes.attachment_link.readable_text
When Johannes Kepler was born in the late 16th century, people thought that planets in the solar system traveled in circular orbits around Earth. An occasional problem - such as Mars appearing to suddenly reverse course - was solved by the addition of miniature circles, or epicycles, to planetary paths. But Kepler not only adamantly defended the idea that planets orbit the sun, he also revealed that their paths were not perfect circles. His descriptions of planetary motions became known as Kepler's laws. Today, these laws not only describe planetary motion but also determine the orbits of satellites and space stations.

[See also our overview of Famous Astronomers and other scientists who have contributed to the rich history of discoveries in astronomy.]

Born in December 1571, in Weil der Stadt in Swabia, in southwest Germany, young Johannes Kepler was a sickly child of poor parents. He was awarded a scholarship to the University of Tübingen, where he studied to become a Lutheran minister. While there, he was introduced to the work of Nicolaus Copernicus, who had written that the planets orbited the sun rather than Earth.

In 1594, Kepler became a professor of mathematics at a seminary in Graz, Austria, as well as district mathematician and calendar maker. In his spare time, he continued to study astronomy and astrology (which were virtually the same thing back then). In 1596, Kepler wrote the first public defense of the Copernican system. This was a dangerous stance, given that in 1539, Martin Luther, founder of the Lutheran church, derided the theory when he first heard it, while the Catholic church deemed such a position heretical in 1615 (they later subjected astronomer Galileo Galilei to house arrest for his publication on the subject, though the arrest may have had more to do with the fact that he had insulted the pope).

German astronomer Johannes Kepler used mathematics to calculate the path of the planets, finding that they traveled not in circles, as long expected, but in ellipses.

Credit: Johnnes Kepler Gesammelte Werke , C. H. Beck, 1937

"The era in which Kepler lived was one of tremendous upheaval and change," Dan Lewis, curator of the history of science and technology at the Huntington Library in San Marino, Calif., said on NASA's JPL website. "Religious leaders were reluctant to relinquish their ideas about the heavens. Talk by astronomers of a sky filled with objects moving in non-circular orbits and other phenomena that went against an Earth-centric model threatened their beliefs."

Actually, Kepler's motivation was not to upset the church. Rather, his defense of the Copernican model was not on physical or mathematical grounds - Kepler's argument was religious, astrophysicist Paul Sutter wrote in a Space.com "Expert Voices" column. According to Sutter, Kepler said that since the son of God was at the center of the Christian faith, the sun ought to be at the center of the universe.

Nevertheless, according to Lewis, Kepler and his first wife, Barbara, created a code with which to write letters to each other so that their correspondence would not put them at risk of persecution.

In search of the most detailed notes about the paths of the planets, Kepler contacted astronomer Tycho Brahe. A wealthy Danish nobleman, Brahe built an observatory in Prague where he tracked the motions of the planets and maintained the most accurate observations of the solar system at the time. In 1600, Brahe invited Kepler to come work with him.

Brahe, however, became suspicious and unwilling to share his notes with his assistant. Instead, he assigned Kepler to solve the mystery of Mars, one of the most puzzling problems in astronomy at the time. Ironically, the detailed records of the challenging planet were the tools Kepler needed to understand how the solar system functioned.

When Brahe died in 1601, Kepler managed to acquire Brahe's observations before his family could use them to their financial benefit.

In 1901, scientists opened up Brahe's grave and claimed to find mercury in his remains. Kepler was posthumously accused of poisoning his benefactor in order to get hold of his closely guarded notes. But when Brahe's body was exhumed again in 2010, tests revealed that the mercury content in his body was not high enough to kill him.

"In fact, chemical analyses of the bones indicate that Tycho Brahe was not exposed to an abnormally high mercury load in the last five to ten years of his life," researcher Kaare Lund Rasmussen, an associate professor of chemistry at the University of Southern Denmark who analyzed mercury levels in Brahe's beard and bones, said in a statement.

Accused of murder long after his death, Kepler's name was finally cleared.

The Martian problem, which Kepler said he would solve in eight days, took nearly eight years. Astronomers had long struggled to figure out why Mars appeared periodically to walk backward across the night sky. No model of the solar system - not even Copernicus' - could account for the retrograde motion.

Using Brahe's detailed observations, Kepler realized that the planets traveled in "stretched out" circles known as ellipses. The sun didn't sit exactly at the center of their orbit, but instead lay off to the side, at one of the two points known as the foci. Some planets, such as Earth, had an orbit that was very close to a circle, but the orbit of Mars was one of the most eccentric, or widely stretched. The fact that planets travel on elliptical paths is known as Kepler's First Law.

Mars appeared to move backward when Earth, on an inner orbit, came from behind the red planet, then caught up and passed it. Copernicus had suggested that observations made from a moving Earth (rather than a centrally located one) could be a cause of the retrograde motion, but the perfect circular orbits he posited still required epicycles to account for the paths of the planets. Kepler realized that two planets, traveling on ellipses, would create the appearance of the red planet's backward motion in the night sky.

Kepler also struggled with changes in the velocities of the planets. He realized that a planet moved slower when it was farther away from the sun than it did when nearby. Once he understood that planets traveled in ellipses, he determined that an invisible line connecting the sun to a planet covered an equal amount of area over the same amount of time. He posited this, his Second Law, along with his first, which he published in 1609.

Kepler's Third Law was published a decade later, and recognized that the relationship between the period of two planets - the time they take to orbit the sun - is connected to their distance from the sun. Specifically, the square of the ratio of the period of two plants is equal to the cube of the ratio of their radius. While his first two laws focus on the specifics of a single planet's movement, his third is a comparison between the orbit of two planets.

"It was this law, not an apple, that led Newton to his law of gravitation. Kepler can truly be called the founder of celestial mechanics," NASA says in its Kepler biography.

h2>Other notable discoveries

Though Kepler is best known for defining laws regarding planetary motion, he made several other notable contributions to science. He was the first to determine that refraction drives vision in the eye, and that using two eyes enables depth perception. He created eyeglasses for both near and farsightedness, and explained how a telescope worked. He described images and magnification, and understood the properties of reflection.

Kepler claimed that gravity was caused by two bodies, rather than one, and as such, the moon was the cause of the motion of tides on the Earth.

"If the Earth ceased to attract the waters of the sea, the seas would rise and flow into the moon," Kepler wrote, according to Michael Fowler, a physics professor at the University of Virginia. "If the attractive force of the moon reaches down to the Earth, it follows that the attractive force of the Earth, all the more, extends to the moon and even farther."

He suggested that the sun rotates, and created the word "satellite." He tried to use his knowledge of the distance Earth travels to measure the distance to the stars. Kepler also calculated the birth year of Christ.

In recognition of his contribution to his our understanding of the motion of the planets, NASA named their planet-finding telescope after the German astronomer.

Additional resources

Follow Nola Taylor Redd at @NolaTRedd, Facebook, or Google+. Follow us at @Spacedotcom, Facebook or Google+.

# data[].attributes.attachment_link.title
Johannes Kepler: Unlocking the Secrets of Planetary Motion

# data[].attributes.attachment_link.description
When Johannes Kepler was born in the late 16th century, people thought that planets in the solar system traveled in circular orbits around Earth. An occasional problem - such as Mars appearing to suddenly reverse course - was solved by the addition of miniature circles, or epicycles, to planetary paths.

# data[].attributes.body
He lived in Prague and He was a German.

He was an assistant of Tycho Brahe.

After Tycho Brahe died He worked on proving that the orbits are ellipse.

# data[].attributes.body
Galileo lived in Italy.

He was known for improving the telescope and alsosupported the idea of copernicus.

# data[].attributes.attachment_link.readable_text
Danish astronomer Tycho Brahe made the most accurate celestial observations of his time and challenged the prevailing belief in how the universe was organized. And while most people may think of scientists as stodgy academic types, Brahe's flamboyant lifestyle and ignominious death would have made some of today's wild celebrities look like choirboys.

Born in Denmark in 1546, Brahe's parents were members of nobility. He was raised by his wealthy uncle, and attended universities in Copenhagen and Leipzig. Though his family badgered him to study law, Brahe chose instead to pursue astronomy.

In 1566, 20-year-old Brahe fought a fellow student in a duel over who was the better mathematician. As a result, he lost a large chunk of his nose. For the rest of his life, he donned a metal prosthetic to cover the disfigurement.

Brahe died in 1601 at the age of 54. While attending a banquet, societal customs did not allow him to excuse himself before his host. Brahe had drunk excessively, but refused to leave to use the bathroom. It is thought that this caused his bladder to burst and led to his subsequent death.

However, scientists who opened Brahe's grave in 1901 to mark the 300th anniversary of his death claimed to find mercury in his remains, fueling rumors that the astronomer was poisoned. Some even accused a jealous Johannes Kepler of the crime.

Brahe's body was exhumed again in 2010. Tests on his bones and beard hairs showed that mercury concentrations in his body were not high enough to have killed him.

"In fact, chemical analyses of the bones indicate that Tycho Brahe was not exposed to an abnormally high mercury load in the last five to ten years of his life," researcher Kaare Lund Rasmussen, an associate professor of chemistry at the University of Southern Denmark who analyzed mercury levels in Brahe's beard and bones, said in a statement.

However, further research revealed that the astronomer was exposed to high levels of gold in his lifetime. "We found traces of gold in Tycho Brahe's hair, and we can establish that he was exposed to gold while these hairs were still on his body," Rasmussen said in a 2016 statement.

"It may have been the cutlery and plates of gold, or maybe the wine he drank contained gold leaf. It's also possible that he concocted and consumed elixirs containing gold, or that he worked with alchemy,"

Researchers also found that greenish stains around the nasal areas of Brahe's corpse contained traces of copper and zinc, indicating that his fake nose was made of brass and not silver or gold, as many had believed.

"When we exhumed the body in 2010, we took a small bone sample from the nose so that we could examine its chemical composition," project leader Jens Vellev, an archaeologist at Aarhus University in Denmark, said the same statement. "Surprisingly, our analyses revealed that the prosthesis was not made of precious metals, as was previously supposed ... So Tycho Brahe's famous 'silver nose' wasn't made of silver after all."

When Brahe was born, his Danish name was Tyge Otteson Brahe. However, he adopted a Latinized form, Tycho Brahe, when he was about 15 years old. There is not much consensus about how the name is pronounced in English. Some say his first name is "tee-ko"; others say "tie-ko." His last name is pronounced either "brah," "bra-hay" or "bra-hee." He is sometimes referred to only by his first name, as in Tycho Crater on the moon, the Tycho Deep Space capsule and Tycho's Supernova Remnant.

Despite his colorful life and death, Brahe contributed a great deal to the field of astronomy. At the time, astronomers held to the idea that the heavens were composed of separate individual spheres, with everything revolving around the Earth. [See also our overview of Famous Astronomers and great scientists from many fields who have contributed to the rich history of discoveries in astronomy.]

This image comes from a very deep Chandra observation of the Tycho supernova remnant. Low-energy X-rays (red) in the image show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave, a shell of extremely energetic electrons. These high-energy X-rays show a pattern of X-ray "stripes" never previously seen in a supernova remant.

Credit: X-ray: NASA/CXC/Rutgers/K.Eriksen et al.; Optical: DSS

In 1572, Brahe observed a supernova in the constellation of Cassiopeia. Brighter than Venus, the new star remained visible for a year and a half. In 1577, he observed a comet. Current theory taught that both were disturbances in the atmosphere. However, Brahe's precise measurements revealed differently. He proved that the supernova never changed with regard to the surrounding stars, and that the comet orbited beyond the path of the moon, contradicting the idea that the heavens never changed.

In 1575, King Frederick II sought to keep the now-famous Brahe in Denmark by offering him his own island and financial support to study astronomy. There, Brahe built an enormous observatory, where he kept meticulous observations of the heavens. While most astronomers only focused on observing heavenly bodies at specific, unusual points in their orbits, Brahe intently tracked them in their entire visible orbit across the sky, creating the most precise observations made at the time. Some of his measurements were accurate to half an arc minute, which is especially admirable given that they were all made before the advent of the telescope.

Although Brahe's observations revealed the flaws of the current system, he did not embrace Nicolaus Copernicus' newly proposed sun-centered model. Instead, he offered a model that combined the two, setting the moon and sun in orbit around the Earth even as the other five known planets circled the sun. The model became popular among those who wanted to leave the older view behind but weren't ready to embrace the idea of the sun at the center of the solar system.

According to Rice's University's Galileo Project, "Tycho Brahe's contributions to astronomy were enormous." In addition to his observations, he also designed and built instruments, periodically calibrating them and checking their accuracy. "He thus revolutionized astronomical instrumentation."

Brahe's precise measurements laid the foundation for a new understanding of the motion of the planets. German astronomer Johannes Kepler contacted him at the end of the 16th century in an effort to obtain copies of the Danish astronomer's research. Brahe countered with a suggestion that Kepler could work as his assistant, helping him to compile his data.

However, Brahe proved more tightfisted than Kepler had anticipated and refused to share his measurements of the planets and their orbits. Instead, he suggested Kepler work on solving the Mars dilemma that plagued astronomers.

Because of its orbit, Mars appears to occasionally move backwards across the sky, causing many astronomers to suggest epicycles, tiny circles within their orbit. Even Copernicus' suggestion that the planets orbited the sun in circles could not account for the red planet's strange motion.

Kepler, using Brahe's detailed observations, realized that the planets moved around the sun not in circles but in stretched out circles known as ellipses. However, the problem took him almost a decade to solve, and Kepler didn't publish it until well after Brahe's death. Although Brahe's family intended to reap as much financial gain as possible from Brahe's observations, Kepler, by his own admission, less-than-ethically acquired them after Tycho died.

Follow Nola Taylor Redd at @NolaTRedd, Facebook, or Google+. Follow us at @Spacedotcom, Facebook or Google+.

Additional resources

# data[].attributes.attachment_link.description
Danish astronomer Tycho Brahe made the most accurate celestial observations of his time and challenged the prevailing belief in how the universe was organized. And while most people may think of scientists as stodgy academic types, Brahe's flamboyant lifestyle and ignominious death would have made some of today's wild celebrities look like choirboys.

# data[].attributes.body
Tycho Brahe lived in Scania, Denmark

He discovered different types of stars and also a supernova in 1572

# data[].attributes.attachment_link.readable_text
Who Was Copernicus?

Nicolaus Copernicus was born on February 19, 1473 in Torun, Poland. Circa 1508, Copernicus developed his own celestial model of a heliocentric planetary system. Around 1514, he shared his findings inthe Commentariolus. His second book on the topic, De revolutionibus orbium coelestium, was banned by the Roman Catholic Church decades after his May 24, 1543 death in Frombork.

Death

In May of 1543, mathematician and scholar Georg Joachim Rheticus presented Copernicus with a copy of a newly published De revolutionibus orbium coelestium. Suffering the aftermath of a recent stroke, Copernicus was said to have been clutching the book when he died in his bed on May 24, 1543 in Frombork, Poland.

Copernicus' Theory: Heliocentric Solar System

Throughout the time he spent in Lidzbark-Warminski, Copernicus continued to study astronomy. Among the sources that he consulted was Regiomontanus's 15th-century work Epitome of the Almagest, which presented an alternative to Ptolemy's model of the universe and significantly influenced Copernicus' research.

Thanks for watching! Visit Website

Scholars believe that by around 1508, Copernicus had begun developing his own celestial model, a heliocentric planetary system. During the second century A.D., Ptolemy had invented a geometric planetary model with eccentric circular motions and epicycles, significantly deviating from Aristotle's idea that celestial bodies moved in a fixed circular motion around the earth. In an attempt to reconcile such inconsistencies, Copernicus' heliocentric solar system named the sun, rather than the earth, as the center of the solar system. Subsequently, Copernicus believed that the size and speed of each planet's orbit depended on its distance from the sun.

Thanks for watching! Visit Website

Thanks for watching! Visit Website

Though his theory was viewed as revolutionary and met with controversy, Copernicus was not the first astronomer to propose a heliocentric system. Centuries prior, in the third century B.C., ancient Greek astronomer Aristarchus of Samos had identified the sun as a central unit orbited by a revolving earth. But a heliocentric theory was dismissed in Copernicus' era because Ptolemy's ideas were far more accepted by the influential Roman Catholic Church, which adamantly supported the earth-based solar system theory. Still, Copernicus' heliocentric system proved to be more detailed and accurate than Aristarchus', including a more efficient formula for calculating planetary positions.

In 1513 Copernicus' dedication prompted him to build his own modest observatory. Nonetheless, his observations did, at times, lead him to form inaccurate conclusions, including his assumption that planetary orbits occurred in perfect circles. As German astronomer Johannes Kepler would later prove, planetary orbits are actually elliptical in shape.

Legacy

Kepler later revealed to the public that the preface for De revolutionibus orbium coelestium had indeed been written by Osiander, not Copernicus. As Kepler worked on expanding upon and correcting the errors of Copernicus' heliocentric theory, Copernicus became a symbol of the brave scientist standing alone, defending his theories against the common beliefs of his time.

Videos

Related Videos

Fact Check

We strive for accuracy and fairness. If you see something that doesn't look right, contact us!

Citation Information

Article Title

Nicolaus Copernicus Biography

Author

Website Name

The Biography.com website

URL

Access Date

{{$root.currentTime | date:'MMMM d, yyyy'}}

Publisher

Last Updated

Original Published Date

# data[].attributes.attachment_link.description
Nicolaus Copernicus was born on February 19, 1473 in Torun, Poland. Circa 1508, Copernicus developed his own celestial model of a heliocentric planetary system. Around 1514, he shared his findings inthe Commentariolus. His second book on the topic, De revolutionibus orbium coelestium, was banned by the Roman Catholic Church decades after his May 24, 1543 death in Frombork.

# data[].attributes.body
Copernicus lived Royal Prussia, a region os the Kingdom of Poland.

He replaced the earth and sun and said that we and other celestial bodies revolve around sun.

# data[].attributes.attachment_link.title
Who is Claudius Ptolemy? Everything You Need to Know

# data[].attributes.attachment_link.description
Ptolemy was a prominent Greek astronomer and geographer. Read through the article to know more about Ptolemy's profile, childhood and life.

# data[].attributes.body
Ptolemy was from 100-170 AD.

He lived in the city of Alexandria in the Roman province of Egypt.

He said that the other celestial bodies revolve around Earth.