What is an asteroid facts for kids? (2023)

What is an asteroid facts for kids?

An asteroid is a chunk of rock and metal in outer space that is in orbit around the Sun. Asteroids vary in size from just a few feet across to hundreds of miles in diameter. Most asteroids are not round, but are lumpy and shaped like a potato. As they orbit the Sun, they tumble and spin.

The Short Answer:

Asteroids are small, rocky objects that orbit the Sun. Although asteroids orbit the Sun like planets, they are much smaller than planets. Asteroids are small, rocky objects that orbit the sun. Although asteroids orbit the sun like planets, they are much smaller than planets.

Asteroids are rocky objects revolving around the sun that are too small to be called planets. They are also known as planetoids or minor planets. There are millions of asteroids, ranging in size from hundreds of miles to several feet across. In total, the mass of all the asteroids is less than that of Earth's moon.

Asteroids, sometimes called minor planets, are rocky remnants left over from the early formation of our solar system about 4.6 billion years ago. Most of this ancient space rubble can be found orbiting our Sun between Mars and Jupiter within the main asteroid belt.

Asteroids are made of rock, metals and other elements. Some even contain water, astronomers say. Asteroids that are mostly stone sometimes are more like loose piles of rubble. Asteroids that are mostly iron are more, well, rock-solid.

Herschel has long been credited with coining the term asteroids, derived from a Greek word meaning "starlike," because he introduced the term at a meeting of London's Royal Society in May 1802 and later published it in the Society's Philosophical Transactions.

Asteroids range in size from Vesta—the largest at about 329 miles (530 kilometers) in diameter – to bodies that are less than 33 feet (10 meters) across. The total mass of all the asteroids combined is less than that of Earth's Moon.

Asteroids zip through space at astonishing velocities. The speed at which asteroids move depends on their distance to the Sun. The closer they are, the greater the speed. That said, even Earth-crossing asteroids, or NEOs, travel around 25 kilometers per second — yep, per second!

There are three general types of asteroids: carbonaceous, stony, and metallic. They are called C-type, S-type, and M-type asteroids. The names are based on the type of material believed to make up most of the surface material: carbon-rich minerals, stony rocks, or metal.

How strong is an asteroid?

Asteroids with a diameter of 7 meters enter the atmosphere about every 5 years with as much kinetic energy as the atomic bomb dropped on Hiroshima (approximately 16 kilotons of TNT), but the air burst is reduced to just 5 kilotons.

No asteroids have ever been observed to hit the Sun, but that doesn't mean that they don't! Asteroids are normally content to stay in the asteroid belt between Mars and Jupiter, but occasionally something nudges them out of their original orbits, and they come careening into the inner solar system.

Get this—they're essentially space debris left over from when the solar system formed. The word asteroid comes from the Greek asteroeidḗs, meaning “starry” or “starlike” (to be clear, asteroids orbit stars, which makes them more like tiny planets).

Asteroids hit Earth typically at high speeds of 16 to 32 km/sec (10-20 miles/sec).

Asteroids are small, rocky, debris left over from the formation of our solar system around 4.6 billion years ago. There are currently over 822,000 known asteroids.

Some asteroids are known to have contained ice within their rocky structure. This has been hinted at by observed changes in the minerals that make up the asteroids caused by this water - changes known as aqueous alterations.

Short answer: Mostly grey. Long answer: Asteroids are rocky objects that orbit the Sun. They're made of similar materials to rocks on Earth, such as the metals nickel and iron. Just like rocks on Earth, asteroids are generally grey in colour.

While space rocks of this magnitude are likely to hit Earth only every hundred million years or so, NEOs 50 to 100 meters (164 to 328 feet) across can strike much faster, roughly every thousand years, and can destroy a large city or level similarly large areas, and also lead to ecological destruction.

It is FALSE. The average temperature of the surface of an asteroid is -73 degrees Celsius (-100 degrees Fahrenheit).

Do asteroids have oxygen?

The asteroids that are nearest the sun are mostly made of carbon, with smaller amounts of nitrogen, hydrogen and oxygen, while the ones further away are made up of silicate rock.

Most of them are located in the main asteroid belt – a region between the orbits of Mars and Jupiter. Some asteroids go in front of and behind Jupiter. These are called Trojan asteroids. Asteroids that come close to Earth are called Near Earth Objects, NEOs for short.

Asteroids

Discovery of Asteroids

In 1801, while making a star map, Giuseppe Piazzi accidentally discovered a small object 1000 kilometers (600 miles) in diameter between the orbits of Mars and Jupiter. Piazzi named the object Ceres. It was the first asteroid to be discovered. In 1802, two more were discovered.

The impact that ended the age of dinosaurs some 66 million years ago was the worst single day that life on Earth has ever endured. A six-mile-wide asteroid called Chicxulub slammed into the waters off what is now Mexico, triggering a mass extinction that killed off more than 75 percent of Earth's species.