June 18, 2009—The first-ever shoreline discovered on Mars would be a prime place to try and dig up proof of past microbial life on the red planet, researchers have announced.
The newfound shore (seen above as it would have looked filled with water in an artist's rendering) lies along what was once a body of water about the size of North America's Lake Champlain (see map), said the University of Colorado at Boulder team that spotted the feature.
Although most ancient deltas on Mars have been badly eroded by winds, the new lakeshores have been sheltered within a valley just north of the equator called Shalbatana Vallis.
Planetary geologist and lead author Gaetano Di Achille said he and his colleagues first spotted hints of the ancient lake in 2007 in sediment data from European Space Agency's Infrared Imaging Surveyor.
Now the scientists say they have "unambiguous evidence" of the well-maintained shoreline, thanks to high-resolution pictures of the region from NASA's Mars Reconnaissance Orbiter.
The now dry lake is thought to be just three billion years old—which would mean the region was watery 300 million years after Mars's warm, wet period is thought to have ended, the team says.
(Related: "NASA Images Add a Billion Years to Mars's Wet Period?")
Despite the lake's scientific attractiveness, it might be a while before robotic probes can make the trek.
"It wouldn't be that easy to land in the lake," Di Achille said. But "in the future, it will definitely be one of the best places for looking at the presence of life."
Findings appear online in the journal Geophysical Research Letters.