Gale crater on Mars was once home to a massive lake, according to a new finding from the Curiosity rover on the Red Planet. The mobile observatory also discovered that Mount Sharp, the central peak of the crater, was formed by sediment, slowly collected by water flowing into the region, over the course of tens of millions of years.
Analysis of data from instruments on-board Curiosity suggests ancient Mars may have possessed conditions capable of sustaining liquid water in multiple locations around the Red Planet.
"If our hypothesis for Mount Sharp holds up, it challenges the notion that warm and wet conditions were transient, local, or only underground on Mars. A more radical explanation is that Mars' ancient, thicker atmosphere raised temperatures above freezing globally, but so far we don't know how the atmosphere did that," Ashwin Vasavada, deputy project scientist for Curiosity at Jet Propulsion Laboratory, said.
Aeolis Mons, commonly known as Mount Sharp, is three miles tall, and located near the center of the massive Gale Crater. The lower regions of the geological feature exhibit hundreds of layers of rock, which appear to be shaped by the actions of wind, river and lake conditions.
Astronomers have been curious how a layered mountain like Aeolis Mons could have formed inside a large crater.
Curiosity is now studying the Murray formation, a section of rock, 500 feet high, that represents the lowest sedimentary layers of the alien mountain. Researchers now believe rivers on the ancient Martian surface may have carried sediment into the lake, depositing material in a manner similar to that seen in terrestrial river deltas. Water in the lake moved from the north of the water body to the center, carrying the raw material for the future mountain along with it.
"We are making headway in solving the mystery of Mount Sharp. Where there's now a mountain, there may have once been a series of lakes," John Grotzinger of the California Institute of Technology in Pasadena and project scientist for Curiosity, stated in a press release.
The lake that is now Gale Crater changed radically over time, and may have been just a few yards deep at several points during its history. As climate and water supply changed over millions of years, conditions constantly altered, and returned.
"Knowledge we're gaining about Mars' environmental evolution by deciphering how Mount Sharp formed will also help guide plans for future missions to seek signs of Martian life," Michael Meyer, lead scientist for Mars Exploration Program, managed by NASA, told the press.
A video showing a graphic demonstration of the proposed processes behind the formation of Mount Sharp within Gale Crater is available on the Jet Propulsion Laboratory YouTube channel.