Mars once supported lakes of liquid water

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A new study from the team behind NASA's Mars Science Laboratory/Curiosity has confirmed that Mars was once, billions of years ago, capable of storing water in lakes over an extended period of time.

Using data from the Curiosity rover, the team has determined that, long ago, water helped deposit sediment into Gale Crater, where the rover landed more than three years ago. The sediment deposited as layers that formed the foundation for Mount Sharp, the mountain found in the middle of the crater today.

A new study from the team behind NASA's Mars Science Laboratory/Curiosity has confirmed that Mars was once, billions of years ago, capable of storing water in lakes over an extended period of time.

Using data from the Curiosity rover, the team has determined that, long ago, water helped deposit sediment into Gale Crater, where the rover landed more than three years ago. The sediment deposited as layers that formed the foundation for Mount Sharp, the mountain found in the middle of the crater today.

"Observations from the rover suggest that a series of long-lived streams and lakes existed at some point between about 3.8 to 3.3 billion years ago, delivering sediment that slowly built up the lower layers of Mount Sharp," said Ashwin Vasavada, Mars Science Laboratory project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, and co-author of the new Science article to be published Friday, Oct. 9.

The findings build upon previous work that suggested there were ancient lakes on Mars, and add to the unfolding story of a wet Mars, both past and present. Last month, NASA scientists confirmed current water flows on Mars.

"What we thought we knew about water on Mars is constantly being put to the test," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at NASA Headquarters in Washington. "It's clear that the Mars of billions of years ago more closely resembled Earth than it does today. Our challenge is to figure out how this more clement Mars was even possible, and what happened to that wetter Mars."

Before Curiosity landed on Mars in 2012, scientists proposed that Gale Crater had filled with layers of sediments. Some hypotheses were "dry," suggesting that sediment accumulated from wind-blown dust and sand. Others focused on the possibility that sediment layers were deposited in ancient lakes.

The latest results from Curiosity indicate that these wetter scenarios were correct for the lower portions of Mount Sharp. Based on the new analysis, the filling of at least the bottom layers of the mountain occurred mostly by ancient rivers and lakes over a period of less than 500 million years.

Image shows a view from the "Kimberley" formation on Mars taken by NASA's Curiosity rover. The strata in the foreground dip towards the base of Mount Sharp, indicating flow of water toward a basin that existed before the larger bulk of the mountain formed. 

The colors are adjusted so that rocks look approximately as they would if they were on Earth, to help geologists interpret the rocks. This "white balancing" to adjust for the lighting on Mars overly compensates for the absence of blue on Mars, making the sky appear light blue and sometimes giving dark, black rocks a blue cast.  Credit NASA.

Read more at NASA.