text: In March 2013, NASA reported Curiosity found evidence that geochemical conditions in Gale Crater were once suitable for microbial life after analyzing the first drilled sample of Martian rock, "John Klein" rock at Yellowknife Bay in Gale Crater.  The rover detected water, carbon dioxide, oxygen, sulfur dioxide and hydrogen sulfide. Chloromethane and dichloromethane were also detected. Related tests found results consistent with the presence of smectite clay minerals.