spacetoday.net: Early Mars too salty for most life

Posted: Sun, Feb 17, 2008, 6:53 AM ET (1153 GMT)
Opportunity image of Meridiani Planum (NASA/JPL)

While liquid water may have existed on the Martian surface early in the planet's history, that water was too salty to support most known organisms, scientists said Friday. Research simulating the conditions thought to exist in regions of Mars like Meridiani Planum, where NASA's Opportunity rover found evidence for liquid water in the planet's past, found that the water would have had very high salinity, enough so that only a handful of known terrestrial organisms would have been able to survive in it. The water there was also thought to be very acidic, further reducing the odds it could support life. The best locations to look for evidence of past Martian life, scientists said, was in the the geologic record from the planet's first 500-600 million years, when conditions may not have been as acidic and salty.