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> Mars: south polar cap

Mars: south polar cap

author: USGS/Novapix

reference: a-mar04-01200

Image Size 300 DPI: 24 * 33 cm

This mosaic is composed of 18 Viking Orbiter 2 images, acquired on September 28, 1977. The south pole is located just off the lower left edge of the polar cap, and the 0 degree longitude meridian extends toward the top of the mosaic. The large crater near the right edge (named "South") is about 100 km in diameter. These images were acquired during southern summer on Mars; the south polar cap was nearing its final stage of retreat just prior to vernal equinox. The south residual cap is approximately 400 km across, and the exposed surface is thought to consist dominantly of carbon-dioxide frost. This is in contrast to the water-ice surface of the north polar residual cap. It is likely that water ice is present in layers that underlie the south polar cap and that comprise the surrounding layered terrains.

Keywords for this photo:

1977 - ASTRONOMY - CARBON DIOXIDE - IMPACT CRATER - MARS - PLANET - POLE - SOUTH POLE - SOUTHERN HEMISPHERE - VIKING - VIKING 2 -