Depression that results from the impact of a meteorite with a solid object in space.
Impact craters have been discovered on Earth, the Moon, Mars, other planets and satellites, and asteroids; they probably occur on unprotected surfaces of similar bodies throughout the universe. Impact craters are much less common on Earth than on the Moon, partly because friction burns up most of the smaller bodies that enter Earth's atmosphere. Thus, any craters formed on Earth's surface tend to be larger than the average size of all entering meteorites.
Meteorite craters on the surface of the Moon, photographed by Lunar Orbiter IV
By courtesy of National Aeronautics and Space Administration