"A fundamental question for this mission is whether Mars could have supported a habitable environment," writes Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "From what we know now, the answer is yes."
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In September, Curiosity spotted what NASA now claims is evidence of an ancient river on Mars.
The existence of water on Mars is widely accepted, but what NASA's scientists hoped to find was the time at which water was around and how it existed in the environment. Analysis of a rock sample collected by the rover identified carbon, nitrogen, sulfur, hydrogen, oxygen, and phosphorus, which are necessary ingredients for life.
The sample was collected from a rock near the stream bed in Gale Crater last month.
"We have characterized a very ancient, but strangely new 'gray Mars' where conditions once were favorable for life," writes John Grotzinger, Mars Science Laboratory project scientist at the California Institute of Technology in Pasadena, California. "Curiosity is on a mission of discovery and exploration, and as a team, we feel there are many more exciting discoveries ahead of us in the months and years to come."
Nasa's Mars rover will now head to the Yellowknife Bay area on Mars before heading to Gale Crater's central mound, Mount Sharp, according to NASA. Scientists note that more samples will be taken and analyzed at Mount Sharp, and that they hope data from these samples might be able to narrow the "duration and diversity" of habitable conditions.
For more info, check out NASA's Mars mission page.