PIA00009: North Polar Ice Cap
Target Name: Mars
Is a satellite of: Sol (our sun)
Mission: Viking
Spacecraft: Viking Orbiter 1
Instrument: Visual Imaging Subsystem - Camera A
Product Size: 3302 x 2781 pixels (width x height)
Produced By: U.S. Geological Survey
Addition Date: 1996-06-03
Primary Data Set: Viking EDRs
Full-Res TIFF: PIA00009.tif (10.5 MB)
Full-Res JPEG: PIA00009.jpg (952.7 kB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

North polar ice cap of Mars, as seen during mid summer in the northern hemisphere. The reddish areas consist of eolian dust, bright white areas consist of a mixture of water ice and dust, and the dark blue areas consist of sand dunes forming a huge 'collar' around the polar ice cap. (The colors have been enhanced with a decorrelation stretch to better show the color variability.) Shown here is an oblique view of the polar region, as seen with the Viking 1 spacecraft orbiting Mars over latitude 39 degrees north. The spiral bands consist of valleys which form by a combination of the Coriolis forces, wind erosion, and differential sublimation and condensation. In high-resolution images the polar caps are seen to consist of thick sequences of layered deposits, suggesting that cyclical climate changes have occurred on Mars. Cyclical climate changes are readily explained by quasi-periodic changes in the amount and distribution of solar heating resulting from perturbations in orbital and axial elements. Variations in the Earth's orbit have also been linked to the terrestrial climate changes during the ice ages.

Image Credit:
NASA/JPL/USGS

Image Addition Date:
1996-06-03