NASA scientists announced Monday that the mountain explored by the Curiosity Rover may have once been a lake.
The rover landed on Mars in 2012 in the Gale Crater, which is 96 miles in diameter and was formed by an asteroid impact. Scientists have used the rover to investigate Mars and Mount Sharp, a three-mile-high mountain of debris in the middle of the Gale Crater. They believe the layered mountain formed billions of years ago.
Scientists have long wondered about the environment of ancient Mars and why a mountain was in the center of a barren crater. Now, rock images suggest that Mount Sharp formed in a lake bed over millions of years, and the mountain was shaped by sediment deposits. The rover found evidence of lake deposits in the crater, which could mean that Mars' warm, wet period was more recent than scientists previously thought.
"During wet periods, water pooled in lakes where sediments settled out in the center of crater," NASA told Discovery News. "Even during dry periods in the crater center, groundwater would have existed beneath the surface. Then, during the next wet period it would resurface to form the next lake. This alternation of lakes, rivers and deserts could have represented a long-lasting habitable environment."
The scientists are unsure whether microbial life was present in the lake, but Michael Meyer, the lead scientist behind NASA's Mars exploration program, told The Associated Press that the lake had "sufficient time for life to get started and thrive."