eldavojohn writes: Following recent announcements of subsurface water on the red planet, new satellite imagery has revealed definitive proof of ancient lakes of water on Mars. The problem is that the lakes are three billion years old. Scientists had suggested before that sublimation of water — the changing of water from ice directly to gas — had caused the depressions that resembled lakes. But new 3D satellite imagery of the sinuous channels connecting the lakes reveal that they could only have been lakes with connecting waterways like rivers and streams. The ancient history of Mars just became a whole lot more interesting.