Lunar Meteorite NWA 13974

Lunar meteorites are fragments of the moon that landed on Earth. Meteors or comets strike the Moon every day, since the moon has no atmosphere protecting it. However, typically the force is not strong enough to actually loosen a fragment of the moon's surface out of its gravitational influence. Once in a while, the impact is strong enough to strike a rock from the moon into the gravitational field of the earth or sun. Eventually the lunar meteorite makes its way out of orbit and on to Earth. Some of the lunar meteorites that have been orbiting around the sun have been in orbit for several millions of years!