Martian Fossils On Earth: The Story of Meteorite ALH 84001

Martian Fossils On Earth: The Story of Meteorite ALH 84001 — page 5
materials These burn up entirely when they enter the atmosphere leaving only vapor and bits of dust A few meteor causing bodies are large and fall to the ground as meteorites How do scientists recognize a meteorite First the outside of a meteorite shows signs of its fiery trip through the atmosphere It is often oddly shaped and its surface is smooth or glassy Second the rock is out of place It is made of minerals unlike the other rocks around it Sometimes the original meteorite is so huge that it leaves a visible crater on Earth About 10,000 years ago a large rock composed mainly of iron and nickel struck the ground about 50 kilometers 30 miles east