Carbonates identified by the Curiosity rover indicate a carbon cycle operated on ancient Mars
ScienceMAY 1
NASA's Curiosity Rover Finds Key Mineral on Mars
Above: Curiosity Mars rover. Mobility City Technology Museum in Zaha Hadid’s Bridge (Bridge Pavilion), Zaragoza, Spain. Image copyright: Nano Calvo/VWPics/Universal Images Group via Getty Images
The Spin
Narrative A
This groundbreaking find validates climate models that predicted Mars' ancient warm period, and confirms the planet's historic habitability. The presence of siderite proves that Mars once had an active carbon cycle and the necessary atmospheric conditions to support liquid water. This finding opens new possibilities for understanding how Mars transformed from a warm, wet world to today's cold desert planet.
Narrative B
The imbalanced carbon cycle revealed by this discovery suggests a more complex and potentially challenging scenario for the theory of ancient Mars' habitability, as carbon being permanently trapped in rocks rather than released back into the atmosphere may have contributed to the planet's loss of habitability. This geological carbon sequestration could have accelerated Mars' transition to its inhospitable state.