NASA's Curiosity rover discovered siderite (iron carbonate) on Mars, showing the planet once had a carbon cycle. It formed in watery conditions, trapping CO₂.. Some later broke down, releasing CO₂ back—proving Mars' carbon cycle was active but unbalanced. Similar deposits may exist worldwide. - discu.eu

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NASA's Curiosity rover discovered siderite (iron carbonate) on Mars, showing the planet once had a carbon cycle. It formed in watery conditions, trapping CO₂.. Some later broke down, releasing CO₂ back—proving Mars' carbon cycle was active but unbalanced. Similar deposits may exist worldwide. https://www.science.org/doi/10.1126/science.ado9966 4 comments 19/4/2025 science