An artist’s impression of what Mars might have looked like with water, when any potential Martian microbes would have evolved.
Image credit: ESO/M. Kornmesser.

Microbes that rank among the simplest and most ancient organisms on Earth could survive the extremely thin air of Mars, a new study finds.

The martian surface is presently cold and dry, but there is plenty of evidence suggesting that rivers, lakes and seas covered the Red Planet billions of years ago. Since there is life virtually wherever there is liquid water on Earth, scientists have suggested that life might have evolved on Mars when it was wet, and life could be there even now.

“In all the environments we find here on Earth, there is some sort of microorganism in almost all of them,” said Rebecca Mickol, an astrobiologist at the Arkansas Center for Space and Planetary Sciences at the University of Arkansas in Fayetteville, and the lead author of the study. “It’s hard to believe there aren’t other organisms out there on other planets or moons as well.”

Mickol and her team detailed their findings in the paper, “Low Pressure Tolerance by Methanogens in an Aqueous Environment: Implications for Subsurface Life on Mars,” which was published in the journal Origins of Life and Evolution of Biospheres.