It has been called a crackpot idea, but the evidence is building: life on Earth came from Mars, and it was delivered by a meteorite. This rock brought us the element molybdenum, which then could have served as the catalyst for the development of organic molecules, which became the first living things on the planet.

So claims Professor Steven Benner, among others. Benner was speaking at a recent conference in Italy. He said:

This form of molybdenum couldn't have been available on Earth at the time life first began, because three billion years ago the surface of the Earth had very little oxygen, but Mars did. It's yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite, rather than starting on this planet.

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