This data supports a Fifa 14 Ultimate Team Coins proposed theory where Mars has had twooceans in its fetime. One four bilon years ago when warmerconditions prevailed, and another three bilon years go when subsurfaceice melted following a large impact.
This later ocean would have been very temporary. It would onlyhave lasted about a milon years or less, Mouginot estimates, andthen the water would have either frozen back in place or turnedinto vapour and fted gradually into the planet's weakatmosphere.
"I don't think it could have stayed as an ocean long enough forfe to form," Mouginot says.
A recent study from Imperial College London doesn't offer muchgood news for martian fe-hunters, either. Soil analysis at thesite of Nasa's Phoenix mission suggest that surface of Mars has dryas a bone for hundreds of milons of years, making it too hostilefor any fe to survive on the planet's surface.