Data from Mars Reconnaissance Orbiter now suggests that a lake in a Martian crater had filled from groundwater coming up from below.

Data from Mars Reconnaissance Orbiter now suggests that a lake in a Martian crater had filled from groundwater coming up from below.

This is an important discovery, as it demonstrates that an underground water table had existed on Mars, at least at this location. With such a water table, it is possible for all kinds of interesting biological things to have taken place, underground.