Once A Crater Lake On Mars
Eberswalde Crater with river delta (credit: JPL/NASA)
NASA released a spectacular image that confirmed liquid water once flowed on the surface of Mars. This was a long time ago--3+ billion years--but it is an essential piece of evidence needed to determine if life may have ever existed on the Red Planet. The photo shows Eberswalde Crater where a rare example a river delta exists. Channels that once fed into a lake inside the crater are obvious.
According to JPL, deltas form when sediments in the water slow down from a flattening of topography or when the river enters a larger body of water. The reduction in speed of flow causes the sediments to settle out into submerged deposits. The original river channel often diverges into multiple smaller channels that spread apart to form a typical, fan-shaped delta. The preserved structure in Eberswalde Crater provides some of the best evidence that liquid water once flowed across the landscape during the early history of Mars.
Two new perspectives of the Eberswalde Crater, its former lake, and river delta structure from the European Space Agency (credit Mars Express/ESA)
Future Mars missions will continue investigating 'water on Mars' for additional evidence of the potential for life evolved there. The mantra for life remains: follow the water! WHB