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Scientists may have discovered a huge, strangely shaped volcano bigger than Mount Everest on the surface of Mars – and it’s been hiding in plain sight for decades, according to new research.
The possible identification of a previously unknown volcano on Mars has caused a stir in the planetary science community since Mars Institute President Dr. Pascal Lee, lead author of an abstract on the formation, presented the findings on March 13 at the 55th Lunar and Planetary Science Conference in The Woods, Texas.
The research has caused excitement – and attracted some skeptics.
Lee said he and Sourabh Shubham, a doctoral student in geology at the University of Maryland, College Park, have identified a volcano in the Noctis Labyrinthus region of Mars — a gnarled patch of terrain near the equator with a web of canyons. The volcano in the “Labyrinth of Night” may have eluded scientists despite years of satellite observation because it does not rise above the surrounding landscape, Lee said.
“It has also been deeply eroded, eaten up and collapsed by erosion to the point that unless you are really looking for a volcano, you would have a very difficult time discovering it very quickly,” he told CNN.
If the team is right, the revelation could have broad implications for scientists’ understanding of Martian geology. And, Lee said, he hopes the discovery can attract future exploration missions to the area to search for water ice or even signs of life.
The smoking gun
Initially, the research team’s efforts led to a study presented in March 2023 that suggested the Noctis Labyrinthus region may be home to a massive glacier covered in salt deposits.
Since then, Lee and Shubham have been studying data collected by NASA’s Mars Reconnaissance Orbiter, trying to determine whether the water might still be frozen beneath the salt.
The hunt for water ice is crucial: it’s a resource that could be used to power human exploration on Mars or even turned into rocket fuel. However, as he roamed the landscape, Lee said he was struck by “this little lava flow next to the glacier.”
The lava had not yet fully oxidized, a process that would give it the same muddy orange hue as the surrounding surface, Lee said.
That indicated the lava could be relatively fresh — the first indication that an undetected volcano may be lurking nearby.
“We started looking carefully at the landscape,” Lee said. “And indeed, when we examined the high points of this region, we noticed that they formed an arc.”
That arc is reminiscent of a shield volcano, Lee added, a type of volcano also found on Earth. Shield volcanoes are characterized by their wide, gently sloping sides, which appear wider than they are high.
That finding led Lee and Shubham to gather more evidence and ultimately determine that a 30,000-foot (9,022-meter) peak was actually the tip of a volcano on Mars.
That is a few hundred meters higher than Mount Everest, which rises 8,848 meters above sea level.
Mapping Mars
Scientists have already cataloged and named more than a dozen volcanoes on Mars, including Olympus Mons, the highest known volcano in our solar system.
Lee said he and Shubham are working to detail the findings in a peer-reviewed paper, a more detailed work that could lend more credibility to the idea in the scientific community.
But the hypothesis of the existence of the volcano is already attracting attention.
“It’s a big thing,” says Dr. Adrien Broquet, a Humboldt Research Fellow at the German Aerospace Center who has studied volcanoes on Mars. “It’s as high as the highest mountain we have on earth. So it is not a small phenomenon on Mars for which we had a question mark. And we have a lot of question marks (about the surface of Mars).”
A search for life in the Labyrinth of the Night
The journey to identifying this volcano — which the team has tentatively named “Noctis Volcano” — began in 2015, Lee said, when NASA asked the planetary science community to suggest intriguing locations on Mars where the U.S. space agency could host future human exploration missions could land.
Lee proposed a location just east of Noctis Labyrinthus, which was called the ‘Noctis Landing’.
The location could be an ideal place to look for extraterrestrial life on Mars, says Lee, who is also a planetary scientist at the SETI Institute, a nonprofit organization dedicated to looking for evidence of extraterrestrial life.
“Of course we’re not looking for a little green guy with antennas,” Lee said. “But we are looking for microbes that do not fit into the tree of life on Earth.”
Noctis Labyrinthus could be an ideal location for this hunt, according to Lee.
“If you want to look for ancient life, drive east (from Noctis Labyrinthus) into the canyons,” Lee said, referring to Valles Marineris, the largest canyon in our solar system.
There, explorers could “search through the rock layers” to look for fossils, he said.
Or, Lee suggested, a mission could head west to a volcanic region called the Tharsis Plateau, where warm caves could harbor living microbes.
With such tantalizing potential, Lee has committed to studying Noctis Labyrinthus to build a case for sending exploration missions there.
A volcano, a glacier and the history of Mars
The existence of a volcano in Noctis Labyrinthus could also help explain the origins of this bizarre landscape.
Scientists suspect that magma bubbling up from Mars’ interior formed the labyrinthine valleys, but the details are up for debate.
One theory is that as the magma pushed up Mars’ crust, it cracked and splintered, leaving a maze of branching fissures.
Lee favors an alternative theory: this model suggests that the Martian crust in Noctis Labyrinthus is full of ice. And as magma seeped in, the ice and rock beneath the surface melted or evaporated, causing parts of the terrain to collapse.
The existence of a volcano in the region could provide more support for the latter theory, according to Lee.
The science of certainty
Three scientists not involved in the study told CNN they wouldn’t be surprised if a volcano was hidden near Noctis Labyrinthus.
Volcanoes of all shapes and sizes cover the surface of the wider region, including the Tharsis Plateau west of Noctis Labyrinthus.
Dr. However, Ernst Hauber, a staff scientist at the German Aerospace Center’s Institute of Planetary Research, is a geologist in the community who would like to see a peer-reviewed paper before accepting Lee and Shubham’s version of events.
“They are very vague about the chronology, about the timing of the events,” Hauber told CNN, referring to the brief summary that Lee and Shubham published.
One of Hauber’s questions: If the volcano could still be active, as Lee suggests, why hasn’t it poured lava into the surrounding canyons? Why aren’t there more visible signs of lava near the summit? Could this actually be an impact crater that Lee is looking at?
“I’m a little skeptical for a number of reasons,” Hauber said.
Broquet from the German Aerospace Center and Dr. David Horvath – a researcher at the nonprofit Planetary Science Institute in Tucson, Arizona – both said in separate interviews that they would like to see additional data supporting the ideas Lee and Shubham presented.
But Broquet and Horvath said they find the abstract intriguing.
“This seems like a very good candidate (for a volcano),” Horvath said.
Lee said he welcomes input from other scientists as he is eager to see additional evidence to support his research. But he also expresses confidence.
“In this case, I feel like there’s really no room for plausible alternative hypotheses,” Lee said, adding that he is 85% to 90% confident he has located a new volcano on Mars.
“But extraordinary claims require extraordinary evidence,” Lee added, quoting the late astronomer Carl Sagan, for whom he once worked as a teaching assistant.
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