The site where NASA's Mars rover Curiosity landed last year contains at least one lake that would have been perfectly suited for colonies of simple, rock-eating microbes found in caves and hydrothermal vents on Earth.
Analysis of mudstones in an area known as Yellowknife Bay, located inside the rover's Gale Crater landing site, show that fresh water pooled on the surface for tens of thousands -- or even hundreds of thousands -- of years.
PHOTOS: Curiosity Drills Hole Into Mars Rock
"The results show that the lake was definitely a habitable environment," Curiosity lead scientist John Grotzinger, with the California Institute of Technology, told Discovery News.
The really big surprise, however, was that clays drilled out from inside two mudstones and analyzed by the rover are much younger than scientists expected, a finding that extends the window of time for when Mars may have been suitable for life.
"These numbers now overlap with the oldest rocks on Earth that contain evidence of a former biosphere on Earth," Grotzinger said.