We distinguish between meteorites, meteors, and meteoroids. A meteorite is usually a stone or rock that has fallen on Earth from outer space. A meteor is the transient luminous phenomenon when an object passes trough the Earth's atmosphere at high speed. The atmosphere's friction causes it to heat up and glow. A meteoroid is an extraterrestrial object, usually a remnant of a comet (micrometeoroid), an asteroid, or a rock from the Moon or from Mars that was ejected by a violent collision with an asteroid.

Structurally and compositionally meteoroids are related to asteroids although the relationship is often not clear or simple.

Southwest Research Institute: Space Instrumentation Division To report any problems, email: Walter Huebner
Last Updated: 3/12/2009