~ Asteroids are chunks of rock and metal that orbit around the Sun. Scientists think that they are loose material that never formed into planets.
~ The Main Asteroid Belt is located between Mars and Jupiter.
~ The total mass of all the asteroids is less than that of the Moon.
~ There are 26 known asteroids larger than 200 km across. We probably know 99% of the asteroids larger than 100 km across. We've cataloged about half of the asteroids in the 10 km to 100 km size range. Scientists still don't know much about the smaller ones. It's thought there may be as many as a million 1 km sized asteroids may exist.