Meteorites are naturally occurring objects that originate in space and survive a fall to the ground through Earth's atmosphere. Most are remnants of asteroids or possibly comets. However, a few have been shown to be pieces of Moon or Mars that were launched into space by an impact event. While moving through space these objects are known as meteoroids. The bright streaks that they produce while moving through Earth's atmosphere are known as a meteors.
The term meteorite is also used for a meteoroid that has landed on the surface of a celestial body other than earth.
There are three main types of meteorites. The most abundant are stone meteorites which are primarily made up of silicate minerals such as olivine, pyroxene and feldspar. As their name implies, iron meteorites are mainly composed of iron but also contain a significant amount of nickel. The rarest of the three are the stony-iron meteorites. They are a mixture of stony and metallic materials.