Asteroid

Any of the thousands of small rocky objects that orbit around the Sun, most of them between the orbits of Mars and Jupiter (although some pass closer to the Sun that Earth does and others have orbits that take them well beyond Jupiter). The largest asteroid is one called Ceres; it's about as wide as the state of Texas.


 * Asteroid Introduction]
 * Near Asteroid Rendezvous Mission
 * Asteroid and Comet Impact Hazards