The ExoMars mobile rover, tasked with recovering evidence of life on the Red Planet, will touch down in 2021 at one of two sites, scientists announced Wednesday.
“After intense discussions, we have voted for the sites Oxia Planum and Mawrth Vallis,” Frances Westhall, head of research at the Centre for Molecular Biophysics in Orleans, France, told journalists.
The final decision - to be made a few months before the 2020 launch - will in some ways pit scientists against engineers: one site is more varied geologically, while the other is less rocky, and thus easier for the rover to navigate.
Both locations, however, are rich in clay, which makes them promising environments “that may contain traces of past life,” said Westhall, a member of the Mars Analogue for Space Exploration (MASE) consortium.
“We like clay because it attracts organic matter and preserves it.”
Life forms are unlikely to exist on Mars’ barren, radiation-blasted surface.
But traces of methane in the planet’s atmosphere suggest something may have once stirred under the surface, possibly single-celled microbes.