Ais forAsteroid
An asteroid is very similar to a comet - it is a large rock that orbits the sun. Comets have a tail, while asteroids do not.
Smaller rocks, from the size of a grain of sand to a large bounder are called meteoroids. When they enter the Earth's atmosphere, they are called meteors. If they hit the ground, they are called meteorites. The photo is of a meteorite.