University of Colorado/AFP
But according to a scientific research team at the University of Colorado-Boulder, there is finally definitive evidence of a shoreline on the Red Planet. Using images from the Mars Reconnaissance Orbiter, which blasted off from Florida in 2005, UC scientists say they have found traces of a lake some 3.4 billion years old.
Lake Shalbatana appears to have covered as much as 80 square miles, and bottomed out at more than 1,500 feet deep. If accurate, the UC study, which was published in the online edition of the journal Geophysical Research Letters, could trigger a significant shift in our understanding of the history of Mars.
"On Earth, deltas and lakes are excellent collectors and preservers of signs of past life," said Gaetano Di Achille, a researcher at UC, said in a statement. "If life ever arose on Mars, deltas may be the key to unlocking Mars' biological past." He called the find the "first unambiguous evidence of shorelines on the surface of Mars."
Ice on Mars?
Of course, this isn't the first report of possible life on Mars. In 2002, the US orbiter Mars Odyssey detected the presence of ice on Mars' north pole. And almost a year ago to the day, the Mars Phoenix Lander confirmed that frozen water once existed on the planet.
Bonus fact: the team manning the Phoenix probe announced the news by Twitter. "Are you ready to celebrate?" they tweeted. "Well, get ready: We have ICE!!!!! Yes, ICE, *WATER ICE* on Mars! w00t!!! Best day ever!!"
The holy grail?
Speaking to one reporter, Brian Hynek, an assistant professor at UC, couldn't conceal his excitement. "Finding shorelines is a Holy Grail of sorts to us," he said. "Not only does this research prove there was a long-lived lake system on Mars, but we can see that the lake formed after the warm, wet period is thought to have dissipated."
Others warned against jumping to conclusions. Cornell University Mars expert Jim Bell told the Associated Press it was "a neat find," but said he'd like more data – besides images – to supplement the findings.
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