Images captured on Mars show Red Planet’s watery past
ESA’s Mars Express recently captured two images of a 70 km-wide crater and its surrounds, which offer a window into the watery past of the Red Planet.
The scene is a composite of two images taken by the Mars Express in March 2007 and February 2017 and it focuses on a large crater in the Margaritifer Terra region in the southern hemisphere of Mars, and includes a portion of Erythraeum Chaos to the north.
According to ESA, the region is located at the northern edge of Noachis Terra, which at 3.7–4 billion years old, represents some of the oldest and most heavily cratered terrains on Mars
ESA notes that remnants of valley networks across the scene indicate that water once flowed through this region, shaping the features seen today. There are a number of distinctive features inside the 70 km crater, such as the striking light-toned material that is interpreted as exposed bedrock.
‘Chaotic terrain’ is visible both inside and outside the crater, marked by randomly oriented blocks separated by troughs. Such terrain is generally associated with the collapse of the surface above regions where large amounts of subsurface water have been released, for example by the sudden melting of ice. As such, outflow channels often begin in chaos terrains.
This type of terrain may also mark the sites of ancient lakes.