Bernard (crater)

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Bernard
Martian crater Bernard based on day THEMIS.png
Bernard crater based on day-time THEMIS image
Planet Mars
Coordinates 23°36′S 154°18′W / 23.6°S 154.3°W / -23.6; -154.3Coordinates: 23°36′S 154°18′W / 23.6°S 154.3°W / -23.6; -154.3
Diameter 131.0 km
Eponym P. Bernard, a French atmospheric scientist

Bernard is a large crater in the Memnonia quadrangle of Mars, located at 23.6° south latitude and 154.3° west longitude. It is 131.0 km in diameter and was named after P. Bernard, a French atmospheric scientist.[1]

Nearby prominent craters include Cross to the southwest, Comas Sola to the northwest, Kovalsky to the east-southeast and Dejnev to the west. Northeast of Bernard crater is Mangala Valles.

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.