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What exactly are 2D shapes? In this guide, we look at the different types of 2D shape, their names and their properties!

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Regular Polygons

A polygon is a plane (2D) shape with straight sides.
To be a regular polygon all the sides and angles must be the same:

Heptagon - 7 Sides

Nonagon - 9 Sides

Decagon - 10 Sides

More ...

Other Common Polygons

These are 2D shapes, and they are polygons, but not regular polygons:

Curved Shapes

These are also 2D shapes, but are not polygons because they have curves:

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Regular Polygons A polygon is a plane (2D) shape with straight sides. To be a regular polygon all the sides and angles must be the same: Heptagon - 7 Sides Nonagon - 9 Sides Decagon - 10 Sides More ...

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What Are Two Dimensional Shapes?

A two-dimensional (2D) shape can be defined as a flat figure or a shape that has two dimensions - length and width. Two dimensional or 2D shapes do not have any thickness.

2D figures can be classified on the basis of the dimensions they have.

Begin here

Examples of 2D Geometric Shapes

A circle, triangle, square, rectangle, and pentagon are all examples of two-dimensional shapes.

Properties of 2D Shapes

Let's learn 2D shapes names and 2D shapes attributes and properties:

Triangle:

It has three straight sides, three angles, and three vertices.

Square:

It has four sides, four equal angles each measuring 90°. It has four vertices.

Rectangle:

It has four sides, four vertices, and four angles each measuring 90°. The opposite sides of the rectangle are equal in length and they are parallel.

Parallelogram:

It has two pairs of parallel sides. The opposite sides of the rectangle are equal in length. The opposite angles are of equal measure.

Rhombus:

It is a special type of quadrilateral whose all sides are equal in length.

Trapezoid:

It has four straight sides with one pair of opposite sides parallel to each other and the other two sides of it are non-parallel.

Kite:

It has four sides. Sides are grouped into two pairs of equal sides that are adjacent to each other.

Circle:

It is made up of a curved line. It has no corners or edges. It is the set of all those points in a plane whose distance from a fixed point remains constant.

Semi-Circle:

A diameter of a circle divides the circle into two equal parts. Each part is called a semi-circle.

Formula of 2D Shapes

Difference Between 2D Shapes and 3-D Shapes

Fun Fact!
A point is zero-dimensional, while a line is one-dimensional for we can only measure its length.

Solved Examples on Two Dimensional Shapes
Example 1: Which of the following are 2D shapes?
Circle Sphere Cylinder Pentagon Kite Rhombus
Solution:
Circle Pentagon Kite Rhombus

1. A 2D shape has one dimension.

2. A 2D shape has no thickness.

3. The circle is an example of a 2D shape.

4. We can find the volume of a 2D shape.

Solution:

1. False. A 2D shape has two dimensions: length and width.

2. True

3. True

4. False. A 2D shape has no thickness or depth.

Example 3: Match the 2D shape with its property.

(a) Triangle

(i) It has no corners and edges.

(b) Square

(ii) It has one pair of opposite sides parallel to each other while the other two sides are non-parallel.

(c) Circle

(iii) It is a closed figure with three straight sides.

(d) Trapezium

(iv) Each of its angles measures 90°.

Solution: Example 4: Write the number of sides and vertices (corners) each figure has. Solution:

1. A triangle has 3 sides and 3 vertices.

2. A kite has 4 sides and 4 vertices.

3. A circle has 0 sides and 0 vertices.

Practice Problems on Two Dimensional Shapes

Frequently Asked Questions on Two Dimensional Shapes
Is oval a 2D shape? What is a zero-dimensional object?

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What are 2D Shapes? Definition, Names, Properties, Examples

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A 2D shape or two-dimensional shape is a flat figure that has two dimensions-length and width. Learn examples, formulas, properties of 2D shapes and much more!

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Math Antics - Circles, Circumference And Area

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From lighting up our skies to maintaining a geological record of our solar system's history, Earth's closest celestial neighbor plays a pivotal role in the studies of our planet and our solar system.

Earth's Moon is the brightest and largest object in our night sky. The Moon makes Earth a more livable planet by moderating our home planet's wobble on its axis, leading to a relatively stable climate. It also causes tides, creating a rhythm that has guided humans for thousands of years.

The Moon was likely formed after a Mars-sized body collided with Earth several billion years ago.

Earth's only natural satellite is simply called "the Moon" because people didn't know other moons existed until Galileo Galilei discovered four moons orbiting Jupiter in 1610. In Latin, the Moon was called Luna, which is the main adjective for all things Moon-related: lunar.

On April 8, 2024, the Moon's shadow swept across North America, treating millions to a breathtaking view of a total...
Read the Story

Discover More Topics From NASA

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Earth's Moon is the brightest and largest object in our night sky. The Moon makes Earth a more livable planet by moderating our home planet's wobble on its axis, leading to a relatively stable climate. It also causes tides, creating a rhythm that has guided humans for thousands of years.

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Everything you’ve ever wanted to know about the Moon

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The Moon is Earth’s most familiar companion, the closest astronomical object to the Earth. No other planet has a satellite as large in comparison to its own size.

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(Image credit: NASA/GSFC/Arizona State University)

The moon is Earth's most constant companion and the easiest celestial object to find in the night sky.

The rhythm of the phases of the moon has guided humanity for millennia; for instance, calendar months are roughly equal to the time it takes to go from one full moon to the next. But the moon's orbit and phases can seem mysterious. for example, the moon always shows us the same face, but it's always changing size as how much of it we see depends on the moon's position in relation to Earth and the sun.

While it's a satellite of Earth, the moon, with a diameter of about 2,159 miles (3,475 kilometers), is bigger than Pluto. (And there are four other moons in our solar system even bigger than ours.)

The moon is a bit more than one-fourth (27%) the size of Earth, a much larger ratio (1:4) than any other moons to their planets. This means the moon has a great effect on our planet and may even be a major factor in making life on Earth possible.

How did the moon form?

There are various theories about how the moon was created, but recent evidence indicates it formed when a huge collision tore off a chunk of the primitive molten Earth, sending the raw ingredients for the moon into orbit.

Scientists have suggested the impacting object was likely about 10% the mass of Earth and about the size of Mars. Because Earth and the moon are so similar in composition, researchers have concluded that the impact must have occurred about 95 million years after the formation of the solar system, give or take 32 million years. (The solar system is roughly 4.6 billion years old.)

In 2015, new research gave further weight to this theory, using simulations of planetary orbits in the early solar system as well as newly uncovered differences in the abundance of the element tungsten-182 detected in the Earth and the moon.

While this theory, most commonly known as the large impact theory, is the dominant theory in the scientific community, there are several other ideas for the moon's formation. These include the concept that the Earth captured the moon, that the moon fissioned out of the Earth or even that Earth may even have stolen the moon from Venus.

What is the moon made of?

The moon very likely has a very small core, just 1% to 2% of the moon's mass and roughly 420 miles (680 km) wide. It likely consists mostly of iron, but may also contain large amounts of sulfur and other elements.

The moon's rocky mantle is about 825 miles (1,330 km) thick and made up of dense rocks rich in iron and magnesium. Magma in the mantle made its way to the surface in the past and erupted volcanically for more than a billion years - from at least four billion years ago to fewer than three billion years ago.

The crust that includes the lunar surface averages some 42 miles (70 km) deep. The outermost part of the crust is broken and jumbled due to all the large impacts the moon has endured , with the shattered zone giving way to intact material below a depth of about 6 miles (9.6 km).

Like our solar system's four innermost planets, the moon is rocky. It's pockmarked with craters created by asteroid impacts millions of years ago and, because there is no weather, the craters have not eroded.

The average composition of the lunar surface by weight is roughly 43% oxygen, 20% silicon, 19% magnesium, 10% iron, 3% calcium, 3% aluminum, 0.42% chromium, 0.18% titanium and 0.12% manganese.

Orbiting spacecraft have found traces of water on the lunar surface that may have originated from deep underground. They have also located hundreds of pits that could one day house explorers living on the moon long-term.

Ongoing observations from the Lunar Reconnaissance Orbiter (LRO) have shown that water is more abundant on slopes facing the lunar south pole, although scientists do caution that the water quantity is comparable to an extremely dry desert. Meanwhile, a 2017 study suggested the moon's interior could be abundant in water too.

Does the moon have an atmosphere?

The moon has only a very thin atmosphere, so a layer of dust - or a footprint - can sit undisturbed for centuries. And without much of an atmosphere, heat is not held near the surface, so temperatures vary wildly. Daytime temperatures on the sunny side of the moon reach 273 degrees F (134 Celsius); on the night side, it gets as cold as minus 243 F (minus 153 C).

How does the moon's orbit Earth and cause tides?

Here are some statistics from NASA:

Average distance from Earth: 238,855 miles (384,400 km)

Perigee (closest approach to Earth): 225,700 miles (363,300 km)

Apogee (farthest distance from Earth): 252,000 miles (405,500 km)

Orbit circumference: 1,499,618.58 miles (2,413,402 km)

Mean orbit velocity: 2,287 mph (3,680.5 kph)

The moon's gravity pulls at the Earth, causing predictable rises and falls in sea levels known as tides. To a much smaller extent, tides also occur in lakes, the atmosphere and within Earth's crust.

High tides refer to water bulging up from Earth's surface, and low tides when water levels drop. High tide occurs on the side of the Earth nearest the moon due to gravity, and on the side farthest from the moon due to the inertia of water. Low tides occur between these two humps.

The pull of the moon is also slowing the Earth's rotation, an effect known as tidal braking, which increases the length of our day by 2.3 milliseconds per century. The energy that Earth loses is picked up by the moon, increasing its distance from the Earth, which means the moon gets farther away by 1.5 inches (3.8 centimeters) annually.

The moon's gravitational pull may have been key to making Earth a livable planet by moderating the degree of wobble in Earth's axial tilt, which led to a relatively stable climate over billions of years in which life could flourish.

The moon doesn't escape from this interplay unscathed. A new study suggests that Earth's gravity stretched the moon into its oddly distorted shape early in its lifetime.

What is an eclipse?

During eclipses, the moon, Earth and sun are in a straight line, or nearly so. A lunar eclipse takes place when Earth is directly between the sun and the moon, casting Earth's shadow onto the moon's face. A lunar eclipse can occur only during a full moon.

During a full lunar eclipse, because the moon is in shadow, it can appear blood red in the night sky.

Photos:'Ring of fire' solar eclipse 2021: See amazing photos from stargazers

A solar eclipse occurs when the moon passes between the sun and the Earth, casting the moon's shadow onto Earth. A solar eclipse can occur only during a new moon.

Depending on the degree to which the moon blocks the sun as seen from a particular location on Earth, a solar eclipse can be total, annular or partial. Total solar eclipses are rare in a given location because the shadow of the moon is so small on the Earth's surface.

The last total solar eclipse visible from the United States happened in August 2017; the next one will take place in April 2024.

Does the moon have seasons?

The Earth's axis of rotation is tilted about 23.5 degrees in relation to the ecliptic plane, an imaginary disk through Earth's orbit around the sun. This means the Northern and Southern hemispheres point somewhat toward or away from the sun depending on the time of year, varying the amount of solar radiation they receive and causing the seasons.

But the moon's axis is tilted by only about 1.5 degrees, so the moon doesn't experience noticeable seasons. This means that some areas are always lit by sunlight, and other places are perpetually draped in shadow.

Exploring the moon

Early observations from Earth

Some ancient communities believed the moon was a bowl of fire, while others thought it was a mirror that reflected Earth's lands and seas, but ancient Greek philosophers knew the moon was a sphere orbiting the Earth whose moonlight reflected sunlight.

The ancient Greeks also believed the dark areas of the moon were seas while the bright regions were land, which influenced the current names for those places - "maria" and "terrae," Latin for seas and lands, respectively.

The Renaissance astronomer Galileo Galilei was the first to use a telescope to make scientific observations of the moon, describing in 1609 a rough, mountainous surface that was quite different from the popular beliefs of his day that the moon was smooth.

Race to the moon

In 1959, the Soviet Union sent the first spacecraft to impact the moon's surface and returned the first photographs of its far side. This spurred a series of Cold War-era uncrewed missions launched by both the Soviet Union and the United States to observe the moon's surface.

Many of these early moon probes were failures or only partially successful. However, over time, these missions began to return information about the moon's surface and geological history. The United States launched a series of missions dubbed Pioneer, Ranger and Surveyor, while the Soviet Union sent probes under the names Luna and Zond.

The United States sent astronauts to the moon's orbit and surface in the 1960s and 1970s. The first crewed mission to the moon was in 1968, when the Apollo 8 astronauts orbited it.

In 1969, Apollo 11 landed the first astronauts on the moon, followed by five more successful surface missions (and one, Apollo 13, that didn't make to the moon but returned home safely). The moon remains the only extraterrestrial body that humans have ever visited.

The Apollo program's efforts returned 842 lbs. (382 kg) of rocks and soil to Earth for study. Scientists continue to study the rocks, and have made new discoveries as technology has improved. For example, in 2013, water was found in samples from Apollo 15, 16 and 17 - an interesting find given that previous analyses showed these rocks were quite dry.

The Soviet Union remained active in robotic lunar exploration through the 1960s and 1970s. The first robotic lunar sample return mission took place with Luna 16 in September 1970, after multiple failed attempts with other missions.

The Soviets also deployed the first robotic lunar rover, called Lunokhod 1, just two months later. Lunokhod 2, which deployed in 1973, set an off-world distance driving record for more than 40 years, until NASA's long-running but now-defunct Mars Opportunity rover mission surpassed it in 2014 after several years of driving.

Modern missions

After NASA's Apollo program ended and following an interlude of more than a decade, lunar exploration by U.S. spacecraft resumed in the 1990s.

Since then, a host of other government space agencies have also joined the moon rush, including Japan, the European Space Agency, China, India and Israel. China is the only one of those countries to successfully operate on the surface of the moon; landers sent by the latter two nations crash-landed.

Among other countries, Russia, Japan and the United Arab Emirates are discussing future moon missions.

Meanwhile, in 2019, the administration led by President Donald Trump announced that it was directing NASA to work on returning humans to the moon by 2024. The initiative, dubbed the Artemis program, would rely on commercial and international partners to support a sustainable crewed exploration program powered by NASA's heavy-lift rocket, the Space Launch System.
This article was updated on June 10, 2021 by Space.com senior writer Meghan Bartels and again on Dec. 9 by Space.com senior writer Chelsea Gohd.

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Moon Facts: Fun Information About the Earth's Moon

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(Image credit: NASA/GSFC/Arizona State University) The moon is Earth's most constant companion and the easiest celestial object to find in the night sky. The rhythm of the phases of the moon has guided humanity for millennia; for instance, calendar months are roughly equal to the time it takes to go from one full moon to the next.

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A fun activities and games site covering subjects such as sports, animals, history, science, geography, jokes, math, and biographies. Pages are written to be easy to read and understand.

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A Blocks / JavaScript code editor for the micro:bit powered by Microsoft MakeCode.

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In general the Atlantic low-pressure systems are well established by December, and depressions move rapidly eastward in December and January, bringing strong winds with appreciable frontal rainfall to Ireland. Occasionally the cold anticyclone over Europe extends its influence westwards to Ireland, giving dry cold periods lasting several days.

This image details the simulated tracks of storms with a mean sea level pressure value of less than 940 hPa for the period 1981-2000, with a lifetime of at least 12 hours. These results were obtained using an ensemble of regional climate models with a resolution of 18-km. This image is re-produced from the published paper; Ensemble of regional climate model projections for Ireland, Paul Nolan, ICHEC. Future simulations predict that the tracks of these intense storms are expected to extend further south in the period of 2041 -2060, than those in the reference period of 1981-2000.
Nolan (2008) Ensemble of regional climate model projects for Ireland. EPA. Report No. 159
Between February and June, the influence of continental and Greenland anticyclones make these the months of least rainfall. The sea near Ireland is at its coldest in February and March and consequently the rise of mean air temperature is slow in spring. However, on clear days with light winds, afternoon temperatures can reach summer values even in March. In such situations the nights are cold. Air frost is not infrequent at inland locations, even in May. Continental anticyclones blocking Atlantic depressions are usually responsible for dry periods in late spring.

Towards late June or early July the rise in pressure over the ocean and a corresponding fall in pressure over Europe results in the general wind flow at the surface becoming westerly, bringing air with a long ocean track over Ireland, so that cloud cover, humidity and rainfall increase. From mid-July, clear nights tend to be accompanied by heavy dew. Warm air masses of high humidity and daytime heating sufficient to cause thunderstorms are a feature of mid to late summer weather.

With the advance of August there are occasional incursions into the Atlantic of cold northerly air masses and these produce active depressions in late August and September. In September the humid air is exposed to increasing periods of cooling by night and fog is frequent around dawn in low-lying districts.

In October and November westerly winds from the Atlantic pass over relatively warm seas, and frontal rain and post-cold frontal showers tend to be moderate to heavy. The development of anticyclones extending over Ireland in these months can produce very pleasant weather by day. However, fog in these situations is slow to clear in the morning, particularly in November when solar radiation income is low.

From late summer through Autumn there is a risk of former tropical depressions mixing in with the North Atlantic weather pattern depressions to produce severe storms. These are quite rare but are very significant weather events.

The broad sequence described above does not recur regularly each year. In an oceanic climate at the latitude of Ireland, variability of weather in some of the features referred to above may be completely missing over several months in an individual year.

Meteorological Seasons

The change from winter to spring or from summer to autumn is gradual and the general trend is subject to reversals which may last for a week or more. For climatological and meteorological purposes, on the basis of air temperature, seasons are regarded as three - month periods as follows: December to February - winter, March to May - spring, June to August - summer and September to November - autumn. This is a common grouping in the meteorological practice of many countries in the middle and northern latitudes.

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Climate of Ireland - Met Éireann - The Irish Meteorological Service

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In general the Atlantic low-pressure systems are well established by December, and depressions move rapidly eastward in December and January, bringing strong winds with appreciable frontal rainfall to Ireland. Occasionally the cold anticyclone over Europe extends its influence westwards to Ireland, giving dry cold periods lasting several days.

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Categorising the world’s climate into zones helps us understand the conditions in different regions and track how they change.

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Current local times around the world, including (DST) changes.

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What are the different time zones? - BBC Bitesize

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Learn about the different time zones and what time zone the UK falls into. Learn what the Prime Meridian is and how it splits the two hemispheres.

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Build your own system of heavenly bodies and watch the gravitational ballet. With this orbit simulator, you can set initial positions, velocities, and masses of 2, 3, or 4 bodies, and then see them orbit each other.

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The Artemis missions will build a community on the Moon, driving a new lunar economy and inspiring a new generation. Narrator Drew Barrymore and NASA team me…

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How Clouds Are Actually Made (It's Not What You Think) ☁️

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Matt Green

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The Advanced Colors Song | Art Songs | Scratch Garden

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Types Of Clouds - The Dr. Binocs Show | Best Learning Videos For Kids | Peekaboo Kidz

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We see clouds nearly everyday. They float in the sky above us and block out the Sun. Sometimes clouds are white and puffy. Sometimes they are dark and cover the entire sky. Different kinds of clouds can mean different kinds of weather. Meteorologists study the formation and make up of clouds to understand the weather better.

What are clouds made of?

Clouds are made up of tiny droplets or frozen crystals of water.

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Kids learn about clouds including how they form, levels, fun facts, and types of clouds such as cirrus, cumulus, and stratus.

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Interpret data with interactive bar graphs in this activity.

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BrainPOP Jr. - Animated Educational Site for Kids - Science, Social Studies, English, Math, Arts & Music, Health, and Technology