Most asteroids are located in the asteroid belt between Mars and Jupiter.
Asteroids are much smaller than the Earth or the Moon.
The largest one is called Ceres and it is about 933 kilometers across. All other known asteroids are less than 340 km in diameter. The Yukon meteorites are thought to be fragments of a C-type asteroid. In addition, carbonaceous chondrites contain mineral grains even older than the solar system - pieces of dust that formed long ago around far distant stars. When comets approach the sun, they begin to warm and melt.