A small body that orbits the sun. Most asteroids are thought to be the result of debris left over from the formation of the solar system.
Most asteroids occur in the region between Mars and Jupiter.
Collisions among the bodies in the asteroid belt and adjacent planets displace fragments and place them on a collision course with Earth. The asteroid belt is thought to be the source of most meteorites. Energy which travels through space in the form of waves. All electromagnetic radiation travels at light speed - 300,000 kilometres per second in a vacuum. An instrument that uses electrons, instead of light, to produce a magnified image of an object.