Ancient Martian lake was 'potentially habitable': Study

A site high on scientists' list of possible landing places for NASA's Mars 2020 rover, the ancient Martian lake system in Jezero Crater, may have had a potentially habitable environment, says a new study.

"We think Jezero has a really interesting story to tell," said lead researcher Tim Goudge, a graduate student at Brown University in the US.

"It would be a fun place to get to drive around in," Goudge noted in the study that will be published in the Journal of Geophysical Research: Planets.

The researchers completed a new analysis of the Jezero Crater, near Mars's equator. The study found that the onslaught of water that filled the crater was one of at least two separate periods of water activity in the region surrounding Jezero.

"We can say that this one really well exposed location makes a strong case for at least two periods of water-related activity in Mars' history," Goudge noted.

The ancient lake at Jezero Crater was first identified in 2005 by Caleb Fassett, a former Brown University graduate student who is now a professor at Mount Holyoke College.

It is not clear how long the system was active, but seems to have dried out around 3.5 to 3.8 billion years ago. For the new study, Goudge put together a detailed geological and mineralogical map of the entire Jezero Crater paleolake system.

"There were actually two periods of water-related activity. The earlier episode formed the alteration minerals in the watershed, then some time later you had the surface water activity that transported the minerals into the lake," Goudge said.

The water that stood in the lake from the second event does not seem to have chemically altered the rock much, the new study showed.

That helps confirm what previous researchers had suspected: that Jezero was filled with fairly fresh water with a nearly neutral pH -- making it a potentially habitable environment, the researcher noted.