Fenagh (crater)

Fenagh Crater

Fenagh Crater Ejecta, as seen by HiRISE.
Planet Mars
Coordinates 34°40′N 215°46′W / 34.67°N 215.77°WCoordinates: 34°40′N 215°46′W / 34.67°N 215.77°W
Diameter 6.3 km
Eponym Fenagh, Ireland

Fenagh Crater is a crater in the Cebrenia quadrangle of Mars, located at 34.67° North and 215.77° West. It is 6.3 km in diameter and was named after a town in Ireland.[1]

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.

Why are Craters important?

The density of impact craters is used to determine the surface ages of Mars and other solar system bodies.[2] The older the surface, the more craters present. Crater shapes can reveal the presence of ground ice.

References

  1. ↑ Blue, Jennifer. "Fenagh (crater)". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  2. ↑ 2.0 2.1 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.