Mars May Have Been Filled With Microscopic Life, Study Finds

by Sean Griffin
(Photo by NASA/Arizona State University via Getty Images)

According to French scientists, Mars may have had an underground world filled with microscopic organisms, French scientists reported Monday.

However, if they did in fact exist, these organisms would have altered the atmosphere in a way that they caused a Martian Ice Age. This Ice Age would have killed all the organisms, the researchers concluded.

The study displays how life “actually commonly cause[s] its own demise,” said the study’s lead author, Boris Sauterey. Sauterey now serves as a post-doctoral researcher at Sorbonne University.

The findings “are a bit gloomy, but I think they are also very stimulating.,” he said in an email. “They challenge us to rethink the way a biosphere and its planet interact.”

In a study in Nature Astronomy, Sauterey and his team said they used climate and terrain models to evaluate the habitability of the Martian crust. The models evaluate the viability of life some 4 billion years ago. This is when Mars may have been teeming with water and more hospitable than today.

They proposed that hydrogen-gobbling, methane-producing microbes might have flourished just beneath the surface back then. Apparently, several inches of dirt served enough to protect them against harsh incoming radiation.

Anywhere free of ice on Mars could have been filled with these organisms, according to Sauterey. He says it would have been just as they did on early Earth.

Early Mars’ presumably moist, warm climate wold have been in trouble. According to Sauterey, however, hydrogen sucked out of the thin, carbon dioxide-rich atmosphere would damage the life there. While temperatures plunged by nearly minus 400 degrees Fahrenheit, any organisms near the surface likely would have buried deeper in hopes of survival.

French Scientists Talk Weigh In On New Mars Study

On the other hand, microbes on Earth may have helped maintain temperate conditions. Our nitrogen-dominated atmosphere helps survival, the researchers said.

The SETI Institute’s Kaveh Pahlevan said that future models of Mars’ climate need to consider the French research.

Pahlevan led a separate recent study concerning Mars. It claims the planet may have been born wet with warm oceans lasting millions of years. The atmosphere would have been dense and mostly hydrogen back then. That would serve as a heat-trapping greenhouse gas. Eventually that gas was transported to higher altitudes and lost in space, his team put forth.

“What their study makes clear, however, is that if (this) life were present on Mars” during this earlier period, “they would have had a major influence on the prevailing climate,” he said in an email.

The French researchers suggest the unexplored Hellas Planita, or plain, may possess the best clues of past life. They also suggested the Jezero Crater on the northwestern edge of Isidis Planita, where NASA’s Perseverance rover currently is collecting rocks for return to Earth in a decade.

Next, Sauterey wants to look into the possibility that microbial life could still exist deep within Mars.

“Could Mars still be inhabited today by micro-organisms descending from this primitive biosphere?” he said. “If so, where?”