<p>Outcrops in Mawrth Vallis
</p><p>One of the oldest valleys on Mars, Mawrth Vallis holds special interest because of the presence of clay minerals which form only in the presence of water.
</p><p>NASA/JPL/University of Arizona (284 km above the surface, less than 5 km across)
</p>
Source: <a rel="nofollow" class="external text" href="https://www.uahirise.org/ESP_016486_2000">www.uahirise.org/ESP_016486_2000</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/71688597@N05">UAHiRISE (NASA)</a>
2018-11-13 15:56
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/uahirise-mars/45143794234/">ESP_016486_2000</a>