Small pieces of rock travelling through space are called meteoroids. They are smaller than asteroids but bigger than dust. Meteoroids are called meteors or shooting stars if they burn up and create a trail of light as they fall through the Earth's atmosphere.
If it is not completely burnt up by the atmosphere, and it hits the ground, it is then called a meteorite.
Some meteoroids reach the Earth's surface before they burn up entirely, and the rocky meteoroids that create huge craters on impact are called meteorites.
Meteoroids are very small rocky bodies, often no more than a few centimetres across. Unlike asteroids, they do not orbit the Sun but seem to be scattered randomly in space. Many are made of mixtures of rock, carbon and water. They cross the orbit of the Earth all the time and can be seen burning up in the Earth's atmosphere at night, making the faint flashes of light called shooting stars. The larger meteoroids can reach the Earth before they burn up completely. The most famous of these formed Meteor Crater in Arizona, USA.
