The subsurface of Mars could have contained groundwater, and thus been a viable habitat for ancient life, reports a study published online in Nature Geoscience this week. Locations where deep crustal materials have been brought to the surface should therefore be prime targets for future space missions hunting for evidence of life on Mars.

Joseph Michalski and colleagues evaluated the possibility of groundwater upwelling on Mars. They find sediments indicative of groundwater upwelling from the subsurface in McLaughlin Crater, one of the deepest craters on Mars. They suggest that groundwater upwelling may have occurred sporadically on Mars on local scales, leaving behind deposits that could provide clues to subsurface habitability.