Scientists have used a number of lines of evidence to determine that 114 meteorites found on Earth originated from Mars. Collectively, the martian meteorites are often referred to as the SNC meteorites; the letters stand for Shergotty, Nakhla, and Chassigny, three of the primary types of Mars meteorites (named after fall locations). These objects are all relatively young “igneous” rocks, which means they must have come from a planetary body large enough to form different layers and to produce melted rocks or lava (like Earth).
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