Mars was too salty to sustain life for much of its history, according to evidence gathered by the NASA Opportunity rover. High concentration of minerals in water on early Mars would have made it inhospitable to even the toughest microbes, a leading Nasa expert says.
Speaking at the annual meeting of the American Association for the Advancement of Science (AAAS) in Boston, Dr Andrew Knoll, a member of the rover science team he said conditions on Mars in the past four billion years would have been very challenging for life. "It was really salty - in fact, it was salty enough that only a handful of known terrestrial organisms would have a ghost of a chance of surviving there when conditions were at their best," he explained.
Ah well, so no little green men. Perhaps we should settle for little green extremophiles instead?