<a rel="nofollow" class="external text" href="http://static.uahirise.org/images/2016/details/cut/ESP_047074_1030.jpg">Subtle variations in color look like brush strokes</a> as the lightly frosted terrain reflects light. These variations provide a backdrop to some exotic features referred to colloquially as "spiders."
<p>The radial channels branching out from a central depression are formed when the seasonal layer of dry ice turns to gas in the spring and erodes the surface, which is a uniquely Martian landform.
</p>
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace &amp; 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.
NASA/JPL-Caltech/Univ. of Arizona
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