This is incredible. Apparently, that Mars meteorite that hit us some 13,000 years ago contains biogenic magnetite crystals, which are almost certainly due to ancient bacterial life forms.

The team says that microscopic crystals found in the rock are almost certainly fossilised bacteria that have many characteristics in common with bacteria found on Earth.

“The evidence supporting the possibility of past life on Mars has been slowly building up during the past decade,” said David McKay, Nasa chief scientist for exploration and astrobiology.

“This evidence includes signs of past surface water including remains of rivers, lakes and possibly oceans and signs of current water near or at the surface.”

Studies in 1996 originally suggested this, but the debate was pretty hot at the time — new evidence coming from the most recent round of studies refute critics’ claims that this form of crystal could form due to thermal decomposition.

So, now the question is, did life from Earth get seeded up to Mars, vice versa, or did abiogenesis happen on two planets in our solar system? If the third option, then there goes the egocentrism around which most personal-god theism is based — that some divine creator created life on Earth uniquely and life is some kind of rarity that could never happen by itself (no matter how long it was given or how favorable conditions were to such an event). This won’t stop deists and people who worship nature itself but call it “God”, mind you — but such people are far less of a threat to rationality than those that believe in the supernatural.