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Scientists may have discovered a giant, odd-shaped volcano taller than Mount Everest on the surface of Mars – and it’s been hidden for years, according to new research.
The possible identification of a previously unknown Martian volcano has made waves throughout the planetary science community since Mars Institute Chairman Dr. Pascal Lee, lead author of an abstract about the formation, presented the findings on March 13 at the 55th Lunar and Planetary Science Conference in The Woods, Texas.
The research has raised 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 within Mars’ Noctis Labyrinthus region — a gnarled patch of terrain near the equator with a web canyons. The volcano in the “Labyrinth of Night” may have eluded scientists despite years of satellite observation because it does not extend beyond the surrounding landscape, Lee said.
“It’s also deeply eroded, depleted and eroded to the point that unless you’re really looking for a volcano, you’d be hard-pressed to see it very quickly,” he told CNN.
If the team is correct, the revelation could have broad implications for scientists’ understanding of Martian geology. And, Lee said, he hopes the discovery could help 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 resulted in a study presented in March 2023 that suggested that the Noctis Labyrinthus region may have been covered by a huge glacier covered with salt deposits.
Since then, Lee and Shubham have pored over data collected by NASA’s Mars Exploration Orbiter, trying to determine whether water could still be frozen under the salt.
The search for water ice is crucial – it’s a resource that could be used to fuel human exploration of Mars or even be converted into rocket fuel. However, while scouring the landscape, Lee said he was hit by “this little lava flow near the glacier”.
The lava had not yet fully oxidized, a process that would have given it the same muddy orange color as the surrounding surface, Lee said.
This indicated that the lava could be relatively fresh – the first hint that an undetected volcano might be lurking nearby.
“We started looking at the landscape carefully,” Lee said. “And sure enough, 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 said, a type of volcano that also exists on Earth. Shield volcanoes are characterized by their wide, gently sloping sides – appearing wider than they are tall.
This led Lee and Shubham to gather more evidence, eventually determining that the 29,600-foot (9,022-meter) peak was the top of the Martian volcano.
That’s a few hundred feet higher than Mount Everest, which rises 29,029 feet (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 tallest known volcano in our solar system.
Lee said he and Shubham are working to spell out the findings in a peer-reviewed paper, a more detailed work that could give the idea more credibility throughout the scientific community.
But the hypothesis that the volcano exists is already attracting attention.
“It’s a big deal,” said Dr. Adrien Broquet, Humboldt Research Fellow at the German Aerospace Center who has studied Martian volcanoes. “It is as high as the highest mountain in the world. So, it’s not a small feature on Mars that we had a question mark about. And we have plenty of question marks (under the surface of Mars.)”
Search for life in the Labyrinth of Night
The journey to identify this volcano – which the team has tentatively named “Noctis volcano” – began in 2015, Lee said, when NASA asked the planetary science community to suggest interesting sites on Mars where the agency could US space to land human exploration missions in the future.
Lee suggested a location just east of Noctis Labyrinthus, known as “Noctis landing”.
The site could be an ideal place to search for alien life on Mars, said Lee, who is also a planetary scientist at the SETI Institute, a non-profit dedicated to the search for evidence of extraterrestrial life.
“Of course, there is no little green man with antennae,” Lee said. “But we’re looking for microbes that don’t fit the tree of life on Earth.”
Noctis Labyrinthus could be ideally placed for this hunt, according to Lee.
“If you want to look for ancient life, you drive east (from Noctis Labyrinthus) into the canyons,” Lee said, referring to Valles Marineris, the largest canyon in our solar system.
Explorers could “sift through the rock layers” to scour for fossils, he said.
Or, Lee suggested, a mission could go back to a volcanic region called the Tharsis Plateau, where hot caves could harbor living microbes.
With that exciting potential, Lee commits to studying Noctis Labyrinthus to build a case for sending exploratory missions there.
Volcanoes, glaciers and the history of Mars
The presence of a volcano in Noctis Labyrinthus could also help explain the creation of this strange landscape.
Scientists suspect that the labyrinthian valleys were magma that rose from inside Mars, but the details are up for debate.
One theory is that when the magma pushed up on the Martian crust, it cracked and split, leaving behind a maze of branching canyons.
Lee prefers another theory: This model suggests that the Martian crust in Noctis Labyrinthus is full of ice. And when magma descended, it melted or vaporized ice and rock below the surface, causing the terrain to cave in.
It could lend more support to the latter theory that there is a volcano in the region, Lee said.
The science of certainty
Three scientists not involved in the research told CNN they wouldn’t be surprised if a volcano was hidden near Noctis Labyrinthus.
Volcanoes of all shapes and sizes dot the surface of the wider region, including the Tharsis Plateau west of Noctis Labyrinthus.
However, one geologist in the community who would like to see a peer-reviewed paper before accepting Lee and Shubham’s version of events is Dr. Ernst Hauber, a staff scientist at the German Aerospace Center’s Planetary Research Institute.
“They are very vague about chronology, about the timing of events,” Hauber told CNN, referring to the brief abstract Lee and Shubham published.
Among Hauber’s questions: If the volcano could still be active, as Lee suggests, why didn’t it pour lava into the surrounding canyons? Why aren’t there more visible signs of lava near the peak? Could this be the impact crater Lee is looking at?
“I’m a little skeptical for several reasons,” Hauber said.
Broquet of the German Aerospace Center and Dr. David Horvath – a research scientist at the non-profit Planetary Science Institute in Tucson, Arizona – said in separate interviews that they would like to see additional data supporting the ideas presented by Lee and Shubham.
But Broquet and Horvath said the abstract is interesting.
“This seems like a very good candidate (for a volcano),” Horvath said.
Lee said he welcomes input from other scientists, as he seeks additional evidence to support his research. But it also conveys confidence.
“In this case, my sense is that there is really no room for plausible alternative hypotheses,” Lee said, adding that he is 85% to 90% certain that he has found a new Martian volcano.
“But extraordinary claims require extraordinary evidence,” Lee said, citing the late astronomer Carl Sagan, for whom he once worked as a teaching assistant.
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