One of the biggest questions in Mars science may have been answered by the Curiosity rover
Mystery of where all the carbon dioxide went that once made the red planet far more hospitable has puzzled scientists for years
Nasa’s rover Curiosity has discovered elusive pure carbonates on Mars, helping to solve the conundrum of how the planet was once warm enough to enable rivers to flow.1 What’s more, it also provides the first evidence of an ancient carbon cycle similar to that which makes Earth habitable but that it was likely out of balance causing it to ultimately peter out.
Evidence shows that water once flowed on Mars, meaning it must have had a much a thicker atmosphere to create a warmer climate than the planet has today. Scientists have long thought that large amounts of carbon dioxide likely warmed Mars via the greenhouse effect for liquid water to become stable. However, this presented a mystery: where did all of the carbon dioxide go?