NASA’s Curiosity rover has made a groundbreaking discovery on Mars, finding large carbon deposits in the Gale Crater that suggest ancient life may have thrived on the planet. The rover’s findings, published in the journal Science, indicate that the Martian atmosphere contained enough carbon dioxide to support liquid water and potentially life.
The discovery was made at three drill sites within sulfate-rich layers of Mount Sharp in Gale Crater, where scientists found siderite, an iron carbonate material. This finding is significant because it shows that a carbon cycle operated on ancient Mars, bringing scientists closer to understanding whether the red planet was ever capable of supporting life.
Lead author Dr. Ben Tutolo, an associate professor at the University of Calgary, said the discovery represents a “surprising and important breakthrough” in understanding Martian geology and atmosphere. The rover’s mission aimed to explore climate transitions and habitability on ancient Mars, and this finding is a major achievement towards that goal.
The presence of highly soluble salts in the rocks suggests that the Martian atmosphere underwent a dramatic shift from warm and wet to cold and dry conditions. This shift may have impacted Mars’ ability to support life, with the carbon dioxide transforming into rock form as the atmosphere thinned.
Future missions and analysis of other sulfate-rich areas on Mars could confirm the findings and provide more insights into the planet’s early history. The discovery also raises questions about how much of the CO2 from the atmosphere was sequestered and whether this may have contributed to the loss of habitability on Mars.
Dr. Tutolo believes that studying the mechanisms of forming carbonates on Mars can help us understand how to mitigate climate change on Earth. He notes that learning about the collapse of Mars’ warm and wet early days also tells us that habitability is a fragile thing, emphasizing the importance of protecting life-friendly conditions.
The findings are significant because they show that small changes in atmospheric CO2 can lead to huge changes in the planet’s ability to harbor life. Dr. Tutolo highlights that Earth’s uniqueness lies in its ability to sustain life for at least four billion years, while Mars’ early habitability is now uncertain due to a series of environmental changes.
Source: https://phys.org/news/2025-04-curiosity-rover-large-carbon-deposits.html