Rover finds hints of an ancient Martian carbon cycle

Mars has not always been a seemingly lifeless red desert. We have evidence that billions of years ago it had a warm, habitable climate with liquid water in lakes and flowing rivers, which is somewhat confusing, given that Mars is much farther from the Sun than the Earth and that the Sun was much less bright back then. “In order for Mars to be warm enough to host liquid water, there must have been a lot of carbon dioxide in the atmosphere,” says Benjamin Tutolo, a researcher at the University of Calgary. “The question we’ve been asking for at least 30 years was where the record of all this carbon is.” Tutolo led a new study of rock samples collected by the Curiosity rover that might have answered this question. The tallest sediment stack The mystery of Mars’ missing carbon stems from two seemingly conflicting results. On the one hand, we have already found dried riverbeds and lakes on the surface of Mars, so we know there must have been liquid water on its surface at some point. To a ... Read full article.