New images show Mars’ ice-coated winter surface
PARIS, France — One of the latest images of Mars looks more like cookies and cream than it does the so-called Red Planet.
A photo taken this week by the European Space Agency and Roscosmos ExoMars Trace Gas Orbiter’s camera actually shows north polar dunes on Mars.
Winter at the poles causes carbon dioxide ice to cover the dunes in a thin layer. In spring, this layer immediately transforms from ice to vapor and the defrosting happens from the bottom of the dune and works its way up.
This works to trap gas in areas between the ice layer and the sand. When the ice defrosts, gas erupts from the cracks and inevitably, sand follows. That creates the dark “cookies” part of the cookies and cream-style image.
On the right side of the image, crescent-shaped dunes can be seen merging into ridges that point downwind. Scientists can tell by looking at this image that there are secondary winds shaping the dunes.
NASA’s Mars Reconnaissance Orbiter also captured an image from Danielson Crater, the site of an impact that’s 42 miles across in the southwestern region of Mars.
In the crater, the detailed image reveals rock and sand that have become frozen in time after cementing together. The amount of sediment in the crater has varied over the years and some of the areas have resisted erosion while others have been easily erased. This causes almost stair step-like protruding layers, according to NASA.
Sand is represented here in the blue hue, scattered across the ridges.