Martians Invaded Earth 13 000 Years Ago—Maybe

SEP 01, 1996

Ray Ladbury

Okay, never mind that what may have been humankind’s first encounter with extraterrestrial life didn’t have the drama of The War of the Worlds, independence Day or even My Favorite Martian. Never mind that toy companies are now trying to figure out how to bid for the rights to and then market toys patterned after submicrometer‐long extraterrestrial bacteria. What is important is for us to understand the chain of scientific reasoning that has led to the claim that the Allan Hills (ALH) 84001 meteorite may contain fossil evidence of life from Mars.

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