Bernard (crater)

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Bernard
Martian crater Bernard based on day THEMIS.png
Bernard crater based on day-time THEMIS image
PlanetMars
Coordinates23°24′S 154°12′W / 23.4°S 154.2°W / -23.4; -154.2Coordinates: 23°24′S 154°12′W / 23.4°S 154.2°W / -23.4; -154.2
Diameter128 km
EponymP. 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.[1] 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.[2] The peak is caused by a rebound of the crater floor following the impact.[3] 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.[4] 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.

See also[edit]

References[edit]

  1. ^ "Bernard (crater)". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  2. ^ http://www.lpi.usra.edu/publications/slidesets/stones/
  3. ^ Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7. Retrieved 7 March 2011.
  4. ^ Garvin, J., et al. 2002. Global geometric properities of martian impact craters. Lunar Planet Sci. 33. Abstract @1255.