Mars could be full of microbes

Mars could be full of microbes

Cape Canaveral, Florida.— Ancient Mars may have had an environment capable of hosting an underground world full of microscopic organisms, French scientists reported yesterday Monday.

But if they came into existence, these simple life forms would have altered the atmosphere to such an extent that they caused a Martian glaciation that led to their extinction, according to the scientists’ conclusions.

The findings offer a bleak picture of the cosmos. Life, even in its simplest form as microbes, “could actually cause its own demise,” said study lead author Boris Sauterey, a postdoctoral researcher at Sorbonne University.

The results “are a bit grim, but I think they are also very encouraging,” he said in an email. “They challenge us to rethink the way the biosphere and your planet interact.”

In a study published in the journal Nature Astronomy, Sauterey and his team say they used weather and terrain models to assess the habitability of the Martian crust about 4 billion years ago, when the Red Planet was believed to be filled with water and it was much more hospitable than now.

They surmised that the methane-producing, hydrogen-consuming microbes may have thrived tens of inches (centimeters) below the surface back then, enough to shield them from harsh radiation. Any ice-free sector on Mars could have been teeming with these organisms, Sauterey said, just as it was on Earth.

However, the presumed hot, humid climate of ancient Mars would have been at risk from the huge amount of hydrogen sucked out of the thin, carbon dioxide-rich atmosphere, Sauterey noted. As temperatures plummeted by nearly -400 Fahrenheit (-200 Celsius), any organisms living near the surface would have burrowed deeper in an attempt to survive.