Mars. Mosaic of images taken by the Viking I and II probes centred on 30 degrees latitude north and 150 degrees longitude. The north polar cap (white,

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Mars. Mosaic of images taken by the Viking I and II probes centred on 30 degrees latitude north and 150 degrees longitude. The north polar cap (white, top centre) extends up to the 80 degree latitude circle and is formed by a mixture of ice and dust. During the local winter atmospheric carbon dioxide freezes out onto the polar terrain and creates a thin white layer covering a much greater area. The north polar region is surrounded by a vast, sparsely cratered circumpolar plain (upper centre), known as Vastitas Borealis, having a diameter of about 10,000km. The circular feature at lower centre right is the broad plateau on which the volcano Olympus Mons ( high) sits.

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Size: 4793px × 4273px
Photo credit: © US GEOLOGICAL SURVEY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, borealis, cap, cosmology, hemisphere, mars, mosaic, north, planet, planetary, polar, science, vastitas