{{Short description|Crater on Mars}}{{More citations needed|date=December 2025}}{{distinguish|Barnard (Martian crater)}} {{Infobox crater data | titlecolor = #FA8072 | title = Bernard | image = Martian_crater_Bernard_based_on_day_THEMIS.png | caption = Bernard crater based on day-time [[Thermal Emission Imaging System|THEMIS]] image | coordinate_title = [[Mars#Geography|Coordinates]] | globe = Mars | coordinates = {{coord|23.4|S|154.2|W|globe:mars_type:landmark|display=inline,title}} | diameter = 128 km | eponym = P. Bernard, a French atmospheric scientist }}
'''Bernard''' is a large crater in the [[Memnonia quadrangle]] of [[Mars]], located at 23.4° south latitude and 154.2° west longitude. It is 128 km in diameter and was named after P. Bernard, a French atmospheric scientist.<ref>{{gpn|705}}</ref> The floor of the crater contains large cracks, which may be due to erosion.
== Appearance == Impact craters generally have a rim with ejecta around them, in contrast volcanic craters usually do not have a rim or ejecta deposits. As craters get larger (greater than 10 km in diameter) they usually have a central peak.<ref name="lpi.usra.edu">{{Cite web|url=http://www.lpi.usra.edu/publications/slidesets/stones/|title=Stones, Wind, and Ice: A Guide to Martian Impact Craters}}</ref> The peak is caused by a rebound of the crater floor following the impact.<ref name="Kieffer1992">{{cite book|author=Hugh H. Kieffer|title=Mars|url=https://books.google.com/books?id=NoDvAAAAMAAJ|access-date=7 March 2011|date=1992|publisher=[[University of Arizona Press]]|isbn=978-0-8165-1257-7}}</ref> If one measures the diameter of a crater, the original depth can be estimated with various ratios.
Because of this relationship, researchers have found that many Martian craters contain a great deal of material; much of it is believed to be ice deposited when the climate was different.<ref>Garvin, J., et al. 2002. Global geometric properities of martian impact craters. Lunar Planet Sci. 33. Abstract @1255.</ref> Sometimes craters expose layers that were buried. Rocks from deep underground are tossed onto the surface. Hence, craters can show us what lies deep under the surface.
== Gallery == <gallery class="center" widths="190px" heights="180px" > 52438cameramap.jpg|Map showing the relative positions of Bernard Crater and other nearby craters in [[Memnonia quadrangle]] Wikibernard.jpg|West side of Bernard Crater, as seen by CTX camera (on [[Mars Reconnaissance Orbiter]]). Wikibernardclose.jpg|Close-up of part of floor of Bernard Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Wikibernarddevils.jpg|Close-up of part of floor of Bernard Crater showing troughs and [[dust devil tracks]], as seen by CTX camera (on Mars Reconnaissance Orbiter). Image:Bernard Crater Floor.JPG|[[Bernard Crater]] Floor, as seen by [[HiRISE]]. Large cracks are visible on floor. ESP 035163 1560memnoniafractures.jpg|Troughs on the floor of [[Bernard Crater]] showing many boulders, as seen by HiRISE under HiWish program ESP 034596 1565memnoniafractures.jpg|Troughs on the floor of [[Bernard Crater]], as seen by HiRISE under HiWish program </gallery> {{commons category|Bernard_(Martian_crater)}}
== See also == * [[List of craters on Mars]]
==References== {{reflist}} {{Geography of Mars}} {{Portal bar|Solar System}}
[[Category:Memnonia quadrangle]] [[Category:Impact craters on Mars]]