Read our COVID-19 research and news.

Clues to Life May Change Selection of Next Mars Rover Site

<p>A half-scale model of ESA's 2020 Mars rover. It will descend using parachutes and thrusters.</p>

A half-scale model of ESA's 2020 Mars rover. It will descend using parachutes and thrusters.

Yesterday's announcement of methane on Mars--a possible byproduct of life--could influence where NASA's next rover touches down, according to an agency official. One possible target is Nili Fossae, a once-water-rich area that had been in contention until its relatively high altitude put the kibosh on it.

The years-long landing site selection process--open to any planetary scientist--had whittled down a list of sites to seven and then to four, all with the guidance of mission engineers. All of the finalists showed signs of once-flowing water or water-altered minerals. Nili Fossae was a favorite for its clays, which are products of water alteration. Scientists were to pass a single recommended site up the management chain for a final decision this spring by NASA Associate Administrator Edward Weiler.

At yesterday's press conference, NASA's Mars program lead scientist, Michael Meyer, explained that Nili Fossae had been axed because its high altitude made landing problematic. But that was before NASA had to delay the Mars Science Laboratory, a classically ambitious mission whose high-tech instruments and landing system pushed its launch date back to late 2011. It was also before the methane discovery placed Nili Fossae close to one of three sources of the gas. "Adding potential landing sites is possible," said Meyer. "Nili Fossae is not ruled out."