Is Mars still volcanically active? A new study says it might be. Using a spacecraft orbiting the Red Planet, scientists have detected a strong-smelling gas called hydrogen chloride in the atmosphere above cracks in the ground near a giant volcano. On Earth, this gas is often released during volcanic activity. The study, published on November 4, 2026, in the journal Science Advances, does not prove that a volcano is currently erupting on Mars. However, it gives scientists a big new clue in their research of recent volcanic activity on the planet. Let’s walk through what was found, what it means, and what we still don’t know.
Scientists Just Found a Vast Magma System on Mars
Is Mars Still Volcanically Active? The Short Answer
Possibly, but scientists have never actually seen a Martian volcano erupt. According to the researchers, the newly detected gas could be linked to magma, or melted rock, moving deep beneath the planet’s surface. However, they are not claiming that lava is flowing on Mars today. So far, no new lava flow or volcanic eruption has been observed on the Red Planet.
So, if you ask a scientist, “Is Mars still volcanically active?” the careful answer is that it might be, and the evidence is becoming stronger. Mars is home to some of the largest volcanoes in the Solar System, including Olympus Mons, the tallest known volcano. But only a few worlds have confirmed ongoing volcanic activity: Earth, Venus and Jupiter’s moon Io. Mars is not yet on that list. If the new findings are confirmed, they could mean that Mars is not completely inactive inside. Instead, the planet may be in a period of relative dormancy. In simple terms, its volcanic activity may have slowed down, but it has not necessarily stopped forever.
What Did the Spacecraft Find at Alba Mons?
The spacecraft behind this discovery is the ExoMars Trace Gas Orbiter, a joint mission run by the European Space Agency and Russia’s space agency, Roscosmos. It studies the Martian atmosphere from orbit and first detected hydrogen chloride back in 2021. In the latest study, researchers found the gas low in the Martian atmosphere above Alba Mons, a large volcano in the planet’s northern hemisphere.
Alba Mons is the largest volcano on Mars by surface area. It is a shield volcano, which means it is wide and gently sloping, almost like a warrior’s shield lying on the ground. Scientists found large groups of surface cracks, known as fissures, along its slopes. Interestingly, hydrogen chloride was detected in the atmosphere directly above these cracks.
The research team believes the gas may be escaping through these openings. Lead scientist Alexander Trokhimovskiy, from the Space Research Institute of the Russian Academy of Sciences, explained that a similar process happens on Earth. Hydrogen chloride can form when chlorine compounds dissolve in magma. As the magma rises toward the surface, the pressure around it decreases, allowing the gas to escape. It works much like the bubbles that rise and escape when you open a bottle of soda. For anyone asking “Is Mars still volcanically active?”, this is exactly the right place to look.
Why Did It Take So Long to Connect the Gas to Volcanoes?
This is a good question because scientists first detected hydrogen chloride on Mars several years ago. However, they were cautious about linking it to volcanic activity. The gas appeared in a seasonal pattern, was not connected to one specific volcanic location, and scientists were not detecting other volcanic gases, such as sulfur dioxide, at the same time.
The new findings give scientists a clearer picture. Hydrogen chloride now appears in yearly bursts above Alba Mons, particularly over areas with surface cracks. Researchers suspect that ice may block some of these cracks during parts of the year, possibly affecting when the gas can escape. However, this is still an idea that needs further testing, not a confirmed explanation.
There is another interesting difference between Earth and Mars. On Earth, volcanoes usually release much more sulfur dioxide than hydrogen chloride. Mars may behave differently because its rocks and volcanic materials have a slightly different chemical composition. This could help explain why scientists did not detect a strong sulfur signal alongside the hydrogen chloride. These findings are one reason the answer to “Is Mars still volcanically active?” is becoming more interesting. What once looked like no clear evidence of volcanic activity may now point to a possible sign of activity beneath the Martian surface.
Is Mars Still Volcanically Active? Other Clues From Marsquakes and Young Lava
Hydrogen chloride is not the only clue scientists have found. Images taken by spacecraft orbiting Mars show that some volcanoes may have been active within the last few million years. One earlier study even identified a volcanic deposit that could be as young as 50,000 years old. If confirmed, it would be one of the youngest volcanic deposits ever discovered on Mars.
There is another important clue: marsquakes. NASA’s InSight lander recorded several earthquakes on the Red Planet, many of them coming from a region called Cerberus Fossae. In a separate study, researchers from Australia and China identified 47 additional marsquakes that had gone unnoticed before. They suggested that these quakes could be caused by magma moving through the Martian mantle, the layer of rock beneath the planet’s crust.
Each of these findings provides only a small piece of evidence. But when scientists look at them together, an interesting picture begins to emerge. So, is Mars still volcanically active? These combined clues make the possibility more convincing than it once seemed, although scientists still need stronger evidence to confirm it.
What We Still Don’t Know
Let’s be clear about what scientists still don’t know. Detecting a gas does not mean a volcanic eruption is happening. No fresh lava flow has been observed on Mars, and the researchers say more evidence is needed before they can reach a firm conclusion. The team considers volcanic gas escaping through cracks the most likely explanation, but other possible causes have not been completely ruled out.
Until scientists collect more data, the honest answer to “Is Mars still volcanically active?” remains “maybe.” But that is not a disappointing result. It is simply how science works. One discovery gives researchers a new clue, and future observations help them understand what is really happening beneath the Martian surface.
What Could This Mean for Life on Mars?
This is the part many readers may find most interesting, so let’s look at it carefully. Scientists have not found any life on Mars, and this new study does not change that. However, volcanic heat could make a difference. If magma still exists beneath the Martian crust, it could warm certain areas underground. Scientists already know that water is trapped below the Martian surface. On Earth, life is believed to have first appeared billions of years ago in warm, water-rich environments known as hydrothermal systems.
Trokhimovskiy explained that rising magma could melt and heat underground water, creating warm places protected from the harsh conditions on the surface. He described these underground environments as some of the most promising places to search for life on Mars. So, if the answer to “Is Mars still volcanically active?” turns out to be yes, it could give scientists a new place to investigate in the search for life. However, this possibility is still based on an idea, not confirmed evidence. Much more research is needed before scientists can know whether such environments actually exist on Mars.
Final Thoughts
So, is Mars still volcanically active? Scientists cannot say yes just yet, but they cannot rule it out either. A strange gas detected above surface cracks, some surprisingly young volcanic deposits, and a series of marsquakes all suggest that the Red Planet may not be completely inactive beneath its surface.
The next time someone asks you, “Is Mars still volcanically active?” you can say: possibly, and a strong-smelling gas is the latest clue. Scientists now have another reason to look more closely at what is happening deep beneath the surface of Mars.