Do you know Mars had an oasis environment around 3.5 billion years ago? The answer would be obviously NO. Well, NASA's Curiosity rover has found an ancient oasis on Mars. Yes, you read it right. Evidence of ponds scattered across a 100-mile-wide basin called the Gale Crater was found by the Curiosity rover, which discovered mineral salts mixed with sediment in rocks.
It is to be noted that Gale Crater is the leftover geological formation from an impact that changed the surface of Mars. Eventually water and wind filled in the crater and the hardening sediment, carved by wind, created the Mount Sharp geological formation that the Curiosity Rover is scaling right now.
The Rover is taking samples of each layer as it climbs and sending that data back to reveal new information about the environment on Mars over time, NASA said.
On Monday, NASA said, "Streams might have laced the crater's walls," adding that climate fluctuations changed the environment from wet to desert. Importantly, NASA's Curiosity rover had previously found evidence of freshwater lakes on Mars, too.
"We went to Gale Crater because it preserves this unique record of a changing Mars," said William Rapin of Caltech. "When and how long was Mars capable of supporting microbial life at the surface?"
Rapin and his co-authors found salts across a 500-foot-tall section of sedimentary rocks that Curiosity first visited in 2017. The Sutton Island salts suggest that water had collected in pools across the formation in addition to the intermittent very dry periods that the scientists had already discovered.
Rapin speculated that Sutton Island might have resembled saline lakes on South America's Altiplano. Streams and rivers flowing from mountain ranges into this arid, high-altitude plateau lead to closed basins similar to Mars' ancient Gale Crater. Lakes on the Altiplano are heavily influenced by climate in the same way as Gale.
"During drier periods, the Altiplano lakes become shallower, and some can dry out completely. The fact that they're vegetation-free even makes them look a little like Mars," Rapin said.
Importantly, future missions will see NASA’s Curiosity rover driving toward more inclined layers to investigate rock structures.