Mars. Mosaic of images taken by the Viking I and II probes centred on 30 degrees latitude north and 30 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 30 degrees longitude. The north polar cap (white) 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 northern hemisphere is characterised by vast, sparsely cratered plains such as Acidalia Planitia (dark upper centre) which has a diameter of about 2615km. The southern hemisphere is highly cratered and features large canyons system such as Valles Marineris (4000km long) seen at bottom left.

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Size: 3414px × 4139px
Photo credit: © US GEOLOGICAL SURVEY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: acidalia, astronomy, cap, cosmology, hemisphere, imagery, mars, mosaic, north, planet, planetary, planitia, polar, science, viking