According to NASA, a small portion of the asteroid population may be burned-out comets whose ices have evaporated away and been blown off into space. Most asteroids are made of rock, but as we explore and learn more about them we know that some are composed of metal, mostly nickel and iron. The largest asteroid is asteroid Ceres at about 952 km (592 miles) in diameter, and Ceres is so large that it is also categorized as a dwarf planet. The size of what classifies as an asteroid is not extremely well defined, as an asteroid can range from a few meters wide – like a boulder - to objects that are hundreds of kilometers in diameter. Our Solar System contains millions of asteroids, many of which are thought to be the shattered remnants of planetesimals – bodies within the young Sun’s solar nebula that never grew large enough to become planets. Credit: NASA/JPL-Caltech/UCAL/MPS/DLR/IDAĪsteroids are sometimes referred to as minor planets or planetoids, but in general, they are rocky bodies that do not have an atmosphere. The asteroid Vesta as seen by the Dawn spacecraft. You can read a paper about this concept here, and a good article discussing the topic here. In addition to the asteroid belt, however, there have been recent discussions among astronomers about the potential existence of large number asteroids in the Kuiper Belt and Oort Cloud. Sometimes their orbits get perturbed or altered and some asteroids end up coming closer to the Sun, and therefore closer to Earth. Credit: NASAĪsteroids are found mainly in the asteroid belt, between Mars and Jupiter. This can also be called a fireball.Īn artists impression of an asteroid belt. Galaxy: also known as the solar system a system of planets, stars and moons orbiting around a Sun Scientists believe an asteroid might have caused the extinction of the dinosaurs.Another related term is bolide, which is a very bright meteor that often explodes in the atmosphere.Asteroid: a large body in space made of rock and minerals.Meteor: small pieces of rock or minerals that have broken off a larger asteroid. Comet: a large body in space made of rock, ice and frozen gas.When this happens, thousands of little pieces chip off the asteroids. Sometimes asteroids collide or crash into one another. Luckily for the people of Chelyabinsk the meteor exploded in the air and didn’t hit the ground and explode, if it did it would have wiped out the town. The massive shock wave damaged thousands of buildings and injured over 1500 people. In 2013 in area of Russia called Chelyabinsk a meteor over 20 m wide exploded in the air.Most meteorites are small, but larger ones have landed on cars or houses, causing damage.Most of them burn up, but if they land on Earth, they are called meteorites. Meteors enter the Earth’s atmosphere every day. The meteors travel through space and occasionally become caught by a planet’s gravitational pull. Sometimes asteroids collide or crash into one another.Scientists estimate that a massive asteroid hit earth about 65 million years ago wiping out the dinosaurs.Ceres is the largest asteroid and is about 950 km wide.Asteroids are found in the Asteroid Belt between Mars and Jupiter. Keep reading to find out more all about comets, meteors and asteroids. Comets orbit at the very edge of the galaxy, past Pluto.This tail can be seen in the night sky as a bright, quickly-moving light. This melting process causes bits of dust and debris to trail behind the comet. As comets travel close to the Sun, some of the ice melts off and becomes a gas. Fun Facts about Comets, Meteors and Asteroids for Kids Some are only a few feet in size, while others are a mile or more long. Comets, meteors and asteroids are too small to be planets. First, they’re believed to be remnants of the materials that created the Sun and the planets. Comets, meteors and asteroids have several things in common.
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