Proof Of Ancient Freshwater Lake On Mars
The Mars Curiosity Rover has been hard at work over the holidays. This week brings exciting news from its journey to Mount Sharp. According to planetary geologist John Grotzinger, who leads the Curiosity team, it's discovered proof of an ancient freshwater lake that could have sustained life for millions of years.
Mount Sharp is located within Gale Crater, a landmark about the size of the Big Island of Hawaii. Curiosity has been living by a cliff near a break in sand dunes, which are too dangerous for the rover to navigate safely.
More important than the presence of water on Mars, scientists say, is how long it lasts. Curiosity has found proof that this area saw fresh water coming and going for long enough for organisms to evolve. In contrast with the rocks that the Opportunity rover found, full of sulfuric acid, the new mudstones are made of clay, which needs a more neutral pH to form.
Researchers announced early evidence of this lake this year, but new data has offered up details about the rock's composition and age. Grotzinger's study, published this week, suggests that microbes from today's Earth could have survived in the friendly waters of the lake. The New York Times points out that the lake was fertile around the same time that life originated on Earth - about 3.5 billion years ago.