Mars’s heavily cratered southern hemisphere attests to its bombardment by asteroids and the relatively low surface gravity of the red planet (only 38 per cent as strong as the Earth’s) suggests that it would be feasible to launch rocks during a giant impact.īut there was no proof that Martian meteorites had actually landed on Earth until 1983, when NASA scientists analysed the gas bubbles trapped inside impact-melted glass within a basaltic meteorite found in Antarctica. Some stones may have brought water and organic compounds to the Earth, facilitating the origin of life. Some were melted in their parent bodies in others one can discern the raw ingredients of the planets. Stones (95 per cent of meteorite falls): these are silicate rocks (some resembling terrestrial volcanic rocks) derived from melted and unmelted asteroids, the Moon and Mars. A few hundred meteorites come from the Moon and Mars they were ejected by collisions into interplanetary space where they eventually assumed Earth-crossing orbits.Īsteroid meteorites are the oldest rocks around - a few hundred million years older than the oldest existing Earth rocks, and approximately 60 million years older than the Moon itself. The vast majority originate from the asteroid belt and hail from 100 to 150 different asteroids.
They are exceedingly rare: the collective weight of every meteorite known to exist is less than the world’s annual output of gold. Meteorites are small rocks from space that impact the Earth.
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