NASA's Curiosity rover has taken a large step toward fulfilling its objective of finding evidence of past habitability on the Red Planet. It has discovered evidence of conditions conducive to ancient life in a rock.
Last month, Curiosity drilled into a rock named John Klein, after a member of the mission team who died in 2011. The results were announced Tuesday, Mar. 12. The powder contained sulfur, hydrogen, oxygen, phosphorus, and carbon. These elements are believed to be crucial to the formation of life. Also, 20 percent of the sample was composed of clay. This type of clay forms in fresh water on Earth. Calcium sulfate was also present, which suggests that the water responsible for the formation had a neutral or slightly basic pH.
This new evidence does not yet prove beyond a shadow of a doubt that life once existed on Mars, but it does lend credence to the idea since it proves that habitable environments did exist in the past. The next focus will be a search for organic carbon.