News Space A NASA rover finally found Mars’ missing carbon The finding could help explain why Mars lost its habitable climate NASA’s Curiosity rover drilled into different rocks along an 89-meter stretch of terrain on its route up a mountain in an ancient lakebed. Samples from the rocks had carbon-bearing minerals that hint at a long lost carbon cycle and life-friendly climate. NASA By Lisa Grossman 7 seconds ago The carbon that once warmed Mars’ atmosphere has been locked in its rusty rocks for millennia.  That’s the story revealed by a hidden cache of carbon-bearing minerals unearthed by NASA’s Curiosity rover along its route up a Martian mountain. The finding is the first evidence of a carbon cycle on the Red Planet, but also suggests that Mars lost its life-friendly climate because that carbon cycle was slow, researchers report in the April 18 Science. Sign up for our newsletter We summarize the week's scientific breakthroughs every Thursday.