Europe's ExoMars Trace Gas Orbiter has detected a possible signal of hydrogen chloride gas seeping from rifts in the Alba Mons region of Mars, which scientists interpret as emissions from hot magma below the surface, according to a study published Wednesday in Science Advances. The team suggests Alba Mons may host an environment similar to hydrothermal vents on Earth, where life likely arose and continues to thrive, though more research is needed to confirm the emissions.
The study is not the first to suggest magma may be flowing on Mars: NASA's InSight lander interpreted its presence through seismic observations and modelling earlier this year. But first author Alexander Trokhimovskiy, at Russia's Space Research Institute, told Live Science the new findings are the strongest evidence yet of gases being released by dormant volcanoes on Mars.
"Our study offers a complementary and potentially independent line of evidence [of Martian magma]: Atmospheric observations that reveal a possible signature of gas release from a subsurface magmatic system," Trokhimovskiy wrote in an email.
Further work suggested the gas was not just appearing in the warmer spring and summer in Mars' southern hemisphere but also in the winter in the northern hemisphere, Olson noted.
A campaign of special, targeted measurements at that time and place lasted two Mars years, roughly four Earth years, Olson said, increasing the likelihood that scientists are seeing an injection of hydrogen chloride into the atmosphere from volcano-adjacent vents. The scientists confirmed the unseasonal observations in the northern hemisphere, finding a distinct and pronounced signal that then diminishes and falls below the spacecraft's detection threshold, Olson said.
“This inconsistency is more suggestive of a puff of gas entering the atmosphere than of regular atmospheric chemistry,” Olson said. “While the link remains a hypothesis, we have now seen this gas appear locally, and nowhere else, over four Mars years of observations.”
Daniel Mège, a co-author and professor who studies planetary geology at the Polish Academy of Sciences, identified the fissures where the gas may be emerging. He said the complementary evidence from InSight on the ground and TGO circling above helps give the study weight: InSight spotted activity in the crust, while TGO detected the emissions in the atmosphere.
Magma activity is not in itself a sign of life, Mège noted, but Earth's first life-forms came from sites like hydrothermal zones, which have a similar confluence of materials and energy as the potential vents on Mars. Conditions would need to be favorable in that area for at least millions of years to allow life to form, he cautioned.
"If these requirements are met at local scale, at the scale of the seepage structures, then living organisms might wait for us to discover them," Mège told Live Science in an email. "But maintaining stable conditions over such a long period at a very local scale is not obvious."
Analysis
Why This Matters
- The finding, if confirmed, would add to evidence that magma is active beneath the Martian surface, with implications for the planet's internal heat and habitability.
- Alba Mons could become a target for future missions searching for signs of past or present life, given its possible hydrothermal environment.
- The result relies on atmospheric observations and remains a hypothesis, so follow-up measurements will be needed to test it.
Background
Mars is a cold desert planet today, but its volcanoes, including the vast Alba Mons, record a history of extensive volcanism. Hydrothermal vents on Earth, where hot water and dissolved minerals interact with rock, are considered prime candidates for the origin of life. Scientists have long wondered whether similar environments existed, or persist, on Mars.
Key Perspectives
Alexander Trokhimovskiy, Space Research Institute: says the study offers complementary and potentially independent evidence of Martian magma, and that the gas appears locally and nowhere else over four Mars years of observations, though the link remains a hypothesis.
Daniel Mège, Polish Academy of Sciences: says the complementary evidence from InSight and TGO gives the study weight, and that if conditions at the seepage structures were stable for millions of years, living organisms might await discovery, though maintaining such stability at a local scale is not obvious.
What to Watch
- Further analysis of TGO data and independent observations to confirm or refute the hydrogen chloride signal.
- Whether the team's targeted measurement campaign is extended or repeated to test the vent hypothesis.
- Any future mission proposals or orbital observations aimed at Alba Mons and its rifts.
Checked
12 claims in this story checked against 1 source: 11 supported.
Show each claim
- SupportedThe headline says the spacecraft spotted a possible gas signal near Alba Mons that hints at magma below.Latest from Live Science: “Europe's ExoMars Trace Gas Orbiter (TGO) spacecraft spotted a possible signal of hydrogen chloride gas leaking from rifts in the region of Alba Mons”
- SupportedThe summary says researchers need to confirm the hydrogen chloride signal, which may point to conditions like those where life arose on Earth.Latest from Live Science: “Although more research is required to confirm the emissions, the team suggested that Alba Mons may host an environment similar to hydrothermal vents on Earth, where life once likely arose and continues to thrive today.”
- SupportedTGO detected a possible hydrogen chloride signal seeping from rifts in the Alba Mons region.Latest from Live Science: “Europe's ExoMars Trace Gas Orbiter (TGO) spacecraft spotted a possible signal of hydrogen chloride gas leaking from rifts in the region of Alba Mons”
- SupportedScientists interpret the gas as emissions from hot magma below Mars' surface.Latest from Live Science: “Scientists interpret this gas as emissions from hot magma below the regolith of Mars.”
- SupportedThe study was published Wednesday in Science Advances.Latest from Live Science: “The study, published in the journal Science Advances Wednesday (Nov. 4)”
- SupportedInSight interpreted magma's presence through seismic observations and modelling earlier this year.Latest from Live Science: “NASA 's InSight lander interpreted its presence through seismic observations and modeling earlier this year .”
- SupportedTrokhimovskiy told Live Science the findings are the strongest evidence yet of gases being released by dormant Martian volcanoes.Latest from Live Science: “But the new findings are the strongest evidence yet of gases being released by dormant volcanoes on Mars, first study author Alexander Trokhimovskiy , at Russia's Space Research Institute, told Live Science.”
- SupportedTrokhimovskiy said: “Our study offers a complementary and potentially independent line of evidence [of Martian magma]: Atmospheric observations that reveal a possible signature of gas release from a subsurface magmatic system,”Latest from Live Science: “"Our study offers a complementary and potentially independent line of evidence [of Martian magma]: Atmospheric observations that reveal a possible signature of gas release from a subsurface magmatic system," Trokhimovskiy wrote in an email.”
- Partly supportedOlson noted that the gas appeared in northern-hemisphere winter as well as southern-hemisphere spring and summer.Latest from Live Science: “Further work, however, suggested that the gas wasn't just popping up in the warmer spring and summer in Mars' southern hemisphere; it also appeared in the winter in the northern hemisphere, he noted.”
- SupportedThe targeted measurement campaign lasted two Mars years, roughly four Earth years, and increased the likelihood that scientists were seeing a hydrogen chloride injection from volcano-adjacent vents.Latest from Live Science: “That campaign lasted two Mars years — roughly four Earth years — and increased the likelihood that scientists are seeing "an injection" of hydrogen chloride into the atmosphere from volcano-adjacent vents, Olson said.”
- SupportedOlson said the northern-hemisphere signal was distinct and pronounced, then diminished below TGO's detection threshold.Latest from Live Science: “The scientists confirmed the unseasonal observations in the northern hemisphere, finding a "distinct and pronounced signal" that then diminishes and falls below the spacecraft's detection threshold.”
- SupportedMège said life might await discovery if requirements are met at the seepage structures, but stable local conditions over such a long period are not obvious.Latest from Live Science: “"If these requirements are met at local scale, at the scale of the seepage structures, then living organisms might wait for us to discover them," he told Live Science in an email. "But maintaining stable conditions over such a long period at a very local scale is not obvious."”