Bernard (crater)

{{Short description|Crater on Mars}}

{{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 THEMIS image

| coordinate_title = 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.{{gpn|705}} The floor of the crater contains large cracks, which may be due to erosion.

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.{{Cite web|url=http://www.lpi.usra.edu/publications/slidesets/stones/|title=Stones, Wind, and Ice: A Guide to Martian Impact Craters}} The peak is caused by a rebound of the crater floor following the impact.{{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}} 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.Garvin, J., et al. 2002. Global geometric properities of martian impact craters. Lunar Planet Sci. 33. Abstract @1255. 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.

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

{{commons category|Bernard_(Martian_crater)}}