Water ice on Mars’ poles, but not a drop to drink Houston Chronicle

Mars’ north and south poles are loaded with frozen water trapped under a crust of “dry ice” — frozen carbon dioxide — but this is not necessarily good news for any earthly visitor looking for a drink, scientists reported today. Apparent indications of surface water, including features that look like channels and river valleys, suggest the Red Planet might once have been warm and wet enough to sustain liquid water, and therefore to allow for the possibility of Earth-type life. But new findings reported in the current edition of the journal Science show that while there may be lots of water ice, there is nowhere near enough carbon dioxide to ever warm the planet up enough to make the water drinkable.