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NASA’s Mars Science 'Laboratory – Curiosity Rover — was sent to Mars some 16 months ago. Its main objective is to find evidence that a past environment could have been well suited to supporting microbial (微生物的) life.
Today, a team of mission researchers, writing in a series of papers published in the journal Science, said that they found evidence of what was once an ancient freshwater lake on Mars, which might have been capable of supporting life.
The researchers studied a set of sedimentary rocks (沉积岩) that were found in an area on the floor of Gale Crater (盖尔陨石坑) called Yellowknife Bay. These sedimentary rocks, probably formed from ancient Martian mud, have suggested to researchers that there was at least one lake that welled up with drinkable water inside Gale Crater some 3.6 million years ago, and that the lake could have lasted for tens or even hundreds of thousands of years.
“Shortly after landing, we found evidence that liquid water had flowed across the surface long before in Gale Crater,” said Jim Bell, from Arizona State University. “These new results show that in addition to surface water, there was likely an active groundwater system in Gale Crater that significantly weathered ancient rocks and minerals.”