Virrat (crater)

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Ojp201 (talk | contribs) at 19:53, 24 June 2016 (Lisätty linkkejä). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Template:MarsGeo-Crater

Virrat is a Martian impact crater, approximately 54 kilometres in diameter. It is located at 31.1°S, 103°W, southwest of the crater Dinorwic and northeast of Clantas Fossae. Several Virrat crater radii to the north are the craters Koga and Nhill. It is named after a town in Finland,[1] and its name was approved by the International Astronomical Union in 1991.[2][3] According to a surface age map of Mars based on US Geological Survey data, the area around Virrat is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago.[4] At the highest point on its rim, it is about 6,400 metres above zero altitude, and it is about 5,100 metres at the crater bottom, giving it a depth of 1.3 kilometres.[3]

References

  1. ^ There appears to be no such town as Virrat, Sweden, although there does exist a Virrat, Finland, and it is possible the IAU could have made a mistake when naming the crater.
  2. ^ "USGS Astro: Planetary Nomenclature: Feature Data Search Results". USGS Gazetteer of Planetary Nomenclature Feature Information. Retrieved October 22, 2007.
  3. ^ a b NASA World Wind 1.4. NASA Ames Research Center, 2007.
  4. ^ "INTEGRATING GLOBAL-SCALE MISSION DATASETS – UNDERSTANDING THE MARTIAN CRUST" (PDF). lpi.usra.edu. Retrieved October 22, 2007.