Earth is constantly getting pummeled by meteorites. We are unaware of most of them, as they burn up in our atmosphere before they hit the ground. Every now and again, though, something larger gets drawn into Earth's gravitational field — and when this happens, it usually spells bad news for any life living on our planet's surface.
Scientists know that the vast majority of meteorites that come crashing down to Earth originate from the solar system's main asteroid belt: a region between Mars and Jupiter where irregularly shaped rocks left over from the formation of the solar system crash into and bounce off each other during their journeys around the sun.
