NASA’s Curiosity rover has uncovered new evidence that ancient Mars may have been able to support life.
Researchers found large deposits of carbon in rocks inside Gale Crater, a major breakthrough that brings scientists closer to answering one of the biggest space mysteries—was Mars ever habitable?
Dr. Ben Tutolo, a geoscientist at the University of Calgary and a member of the Curiosity rover team, led the new study published in Science.
The rover found a mineral called siderite, which is rich in carbon and iron, in three drilling locations on Mount Sharp, a mountain inside Gale Crater.
This discovery is important because siderite forms in water under certain conditions.
It suggests that ancient Mars once had a thick atmosphere full of carbon dioxide (CO2), which could have kept the planet warm enough for liquid water to exist on the surface.
Scientists have long suspected that Mars started out as a warm, wet planet but eventually lost its atmosphere and became the cold, dry place we see today. The presence of carbonate minerals, like siderite, supports that idea.
These minerals form when CO2 in the air reacts with rocks and becomes locked away underground, reducing the amount of greenhouse gas in the atmosphere and possibly cooling the planet.
Until now, scientists had found only small hints of these carbon-containing rocks on Mars. Finding large deposits is a major step forward. According to Dr. Tutolo, this supports the idea that Mars once had the right conditions to support life.
However, as CO2 was gradually removed from the atmosphere and stored in rocks, the planet’s ability to stay warm—and possibly its habitability—faded.
This Martian discovery also connects with climate work here on Earth. Dr. Tutolo studies how to capture human-made CO2 by turning it into solid carbonates to fight climate change. Understanding how this process happened naturally on Mars could help improve our efforts to do the same on our own planet.
The research offers a deeper look into how Mars changed over time, and how fragile planetary habitability can be. Unlike Earth, which has remained livable for billions of years, something caused Mars to lose that potential. For scientists, that’s both a warning and a call to learn more—not just about Mars, but about how to protect life on Earth.
