The soil on Mars may indeed be teeming with microbes, according to a new interpretation of data first collected more than 30 years ago.
The search for life on Mars appeared to hit a dead end in 1976 when Viking landers touched down on the red planet and failed to detect biological activity.
There was another flurry of excitement a decade later, when Nasa thought it had found evidence of life in a Mars meteorite but doubts have since been cast on that finding.
Today, Joop Houtkooper from Justus-Liebig-University in Giessen, Germany, will claim the Viking spacecraft may in fact have encountered signs of a weird life form based on hydrogen peroxide on the subfreezing, arid Martian surface. ...