Scientist hypothesize that a lake of liquid water once filled Gale crater, and the layers in the mound formed as sediment settled down through the water to the bottom of the lake in this image from NASA Mars Reconnaissance Orbiter.
Scientist hypothesize that a lake of liquid water once filled Gale crater, and the layers in the mound formed as sediment settled down through the water to the bottom of the lake in this image from NASA Mars Reconnaissance Orbiter.