NASA has confirmed that liquid water flows on the present day surface of Mars.

NASA has confirmed that liquid water flows on the present day surface of Mars.
It's been known already there's water in the form of ice on Mars, but the atmosphere and temperature of the red planet always cast some amount of doubt as to whether any water could exist in liquid form.
Apparently such doubts were misplaced. 
The research, published in the journal Nature Geosciences, focuses on dark s