PIA21568: Gullies in Winter Shadow


Gullies in Winter Shadow

Caption:

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Map Projected Browse Image
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This is an odd-looking image . It shows gullies during the winter while entirely in the shadow of the crater wall. Illumination comes only from the winter skylight.

We acquire such images because gullies on Mars actively form in the winter when there is carbon dioxide frost on the ground, so we image them in the winter, even though not well illuminated, to look for signs of activity. The dark streaks might be signs of current activity, removing the frost, but further analysis is needed.

NB: North is down in the cutout, and the terrain slopes towards the bottom of the image.

The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 62.3 centimeters (24.5 inches) per pixel (with 2 x 2 binning); objects on the order of 187 centimeters (73.6 inches) across are resolved.] North is up.

Background Info:

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. 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.

Cataloging Keywords:

Name Value Additional Values
Target Mars
System
Target Type Planet
Mission Mars Reconnaissance Orbiter (MRO)
Instrument Host Mars Reconnaissance Orbiter
Host Type Orbiter
Instrument High Resolution Imaging Science Experiment (HiRISE)
Detector
Extra Keywords Color, Crater, Map, Shadow
Acquisition Date
Release Date 2017-03-21
Date in Caption
Image Credit NASA/JPL-Caltech/Univ. of Arizona
Source photojournal.jpl.nasa.gov/catalog/PIA21568
Identifier PIA21568