There is strong evidence that life existed on Mars 3.6 billion years ago. A NASA funded group of researchers found the first organic molecules of Martian origin; several mineral features characteristic of biological activity and possible microscopic fossils of primitive, bacteria-like organisms on a meteorite from Mars.

There is no doubt that the rock came from Mars. Martian meteorites are younger than most meteorites. However, the conclusive evidence from this meteorite is the measurement of internal gases. The trapped gases match those measured in the Martian atmosphere by the Viking probe.

Still, just as soon as this statement was made the skeptics assembled hotly debating the report. Many criticized the space agency for going public without 100% proof. "You should not go public with evidence that's less than 100% sure. This is much less than 100% sure," said John F. Kerridge, planetary scientist at the University of California," The conclusion is at best premature and more probably wrong." Astronomer Carl Sagan said the facts were, "evocative and very exciting," He concurred with the others though that chemicals alone were no evidence of life.

Why exactly are the skeptics so doubtful and so quick to challenge the findings? Contamination-- the meteorite travel through space for 15 million years. Then settled in Antarctica for 13,000 years until found. The meteorite then sat on a shelf in a lab for 12 years before the findings were made. The organic traces were superficial. The PAH molecules found in the cracks in the meteorite are common in space and could have been trapped in the rock on the journey to earth. Groundwater from Antarctica could also account for the findings.

Maybe yes, maybe no, in any case our search for life out there continues and Mars remains a Fascinating Mystery.