Scientists discover 'noxious gas' coming out of Mars - The Independent

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Scientists have found gas seeping out of Mars, suggesting that something is happening under its surface.

Fresh cracks have been found in the Martian surface, hinting at the fact that the red planet might once have been geologically alive deep inside – and may still be. Researchers believe that gas from inside the planet is making its way up to the surface.

A new study found evidence that the gas hydrogen chloride, coming from ht magma underneath the Martian surface. That suggests there may be a kind of dormant volcanism happening inside the planet.

The European Space Agency's ExoMars Trace Gas Orbiter found hydrogen chloride gas in the atmosphere of Mars in 2021. On Earth, that is often found coming out of magmatic vents – and so scientists speculated that the same thing could be happening on Mars.

Now, in the new research, space scientists have found evidence that there is enough heat inside Mars to support volcanism underneath surface until recently, and perhaps still.

Researchers have long speculated that Mars could be volcanically active. It has the biggest volcanoes in the solar system, though it is not clear how active they are, and sensors on the surface have found "marsquakes" akin to those that shake Earth.

But there have been no actual lava flows or eruptions actually seen on the planet. The new finding suggests that might be happening under the surface, with the gas seeping out from a magma chamber, which they liken to a kind of volcanic plumbing inside the planet.

Researchers believe that, if Mars was once active in this way, it could have led to the conditions for life. Lava coming through the crust could have mixed with groundwater, for instance, creating small spots where life could flourish in similar ways to on Earth.

“Looking for martian life in the seeping fissures of the Alba Mons region would make a lot of sense," said Daniel Mège, professor at the Space Research Centre of the Polish Academy of Sciences and co-lead author of the new paper. "If hydrothermal systems are active, they could contain the ingredients and energy needed for microorganisms to develop, and shield microorganisms from the hostile and changing environment above the surface."

The work is reported in a new paper, 'Enigmatic HCl detections as a potential signature of igneous activity on Mars', in the journal Science Advances.