Swiss Cheese on a Red Planet
Credit | NASA/JPL-Caltech/University of Arizona |
---|---|
Language |
|
Map Projected Browse Image
Click on image for larger version
The Martian south polar cap is a layer of carbon dioxide ice, full of pits that make it look like Swiss cheese. The pits form when the Sun heats the ice and makes it sublimate (transform from a solid to a gas). Because it's at the pole, the Sun never gets very high in the sky, so steep slopes get more heat and sublimate faster, causing pits to form and grow. This is balanced by new carbon dioxide frost that forms on flatter areas.
Compare this image with one we took in 2007. How many differences can you find?
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 24.7 centimeters (9.7 inches) per pixel (with 1 x 1 binning); objects on the order of 74 centimeters (29.1 inches) across are resolved.] North is up.
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.