<p>Thermophysical Boundary – Thermophysical means how a terrain’s temperature responds to sunlight; e.g. an asphalt-covered road across a dusty desert is much warmer at night than the dusty surroundings. The edge of the road is a thermophysical boundary. On Mars these boundaries are between rocky and non-rocky areas.
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NASA/JPL/University of Arizona (255 km above the surface and North is to the right) <a rel="nofollow" class="external text" href="https://www.uahirise.org/PSP_006489_1580">www.uahirise.org/PSP_006489_1580</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/71688597@N05">UAHiRISE (NASA)</a>
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