Changing Frost Patterns in Louth Crater
Changing Frost Patterns in Louth Crater
PSP_007805_2505  Science Theme: Seasonal Processes
This image shows the changing seasonal frost patterns on Louth Crater, located at latitude 70 degrees north. This crater contains a mound covered by water frost that persists throughout the year, which is unusual for this latitude.

The seasonal carbon dioxide frost deposited during northern winter can also reach this latitude. At the time this image was acquired in northern spring, the carbon dioxide frost is in the process of sublimating back into the atmosphere.

There are sand dunes near the edge of the mound, which become clear of frost in the summer. This cutout shows a comparison of these dunes acquired in late northern summer with the newer image. It is hard to believe this is the same piece of ground because the brightness patterns are so different due to the large temperature changes throughout the year.

Written by: Alfred McEwen  (7 May 2008)
Acquisition date
26 March 2008

Local Mars time

Latitude (centered)

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316.1 km (196.4 miles)

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56°, with the Sun about 34° above the horizon

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50.3°, Northern Spring

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NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona.