Noachis quadrangle

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Noachis quadrangle
USGS-Mars-MC-27-NoachisRegion-mola.png
Map of Noachis quadrangle from Mars Orbiter Laser Altimeter (MOLA) data. The highest elevations are red and the lowest are blue.
Coordinates 47°30′S 330°00′W / 47.5°S 330°W / -47.5; -330Coordinates: 47°30′S 330°00′W / 47.5°S 330°W / -47.5; -330
Image of the Noachis Quadrangle (MC-27). The northeast includes the western half of Hellas basin. The southeastern region contains Peneus Patera and part of the Amphitrites volcano.

The Noachis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Noachis quadrangle is also referred to as MC-27 (Mars Chart-27).[1]

The Noachis quadrangle covers the area from 300° to 360° west longitude and 30° to 65° south latitude on Mars. It lies between the two giant impact basins on Mars: Argyre and Hellas. Noachis is so densely covered with impact craters that it is considered among the oldest landforms on Mars—hence the term "Noachian" for one of the earliest time periods in martian history. In addition, many previously buried craters are now coming to the surface,[2] where Noachis' extreme age has allowed ancient craters to be filled, and once again newly exposed.

Much of the surface in Noachis quadrangle shows a scalloped topography where the disappearance of ground ice has left depressions.[3][4]

The first piece of human technology to land on Mars landed (crashed) in the Noachis quadrangle. The Soviet's Mars 2 crashed at 44°12′S 313°12′W / 44.2°S 313.2°W / -44.2; -313.2. It weighed about one ton. The automated craft attempted to land in a giant dust storm. To make conditions even worse, this area also has many dust devils.[5]

Scalloped topography[edit]

Certain regions of Mars display scalloped-shaped depressions. The depressions are believed to be the remains of an ice-rich mantle deposit. Scallops are created when ice sublimates from frozen soil. This mantle material probably fell from the air as ice formed on dust when the climate was different due to changes in the tilt of the Mars pole.[6] The scallops are typically tens of meters deep and from a few hundred to a few thousand meters across. They can be almost circular or elongated. Some appear to have coalesced, thereby causing a large heavily pitted terrain to form. The process of producing the terrain may begin with sublimation from a crack because there are often polygon cracks where scallops form.[3][4]

Dust Devil Tracks[edit]

Many areas on Mars experience the passage of giant dust devils. A thin coating of fine bright dust covers most of the Martian surface. When a dust devil goes by it blows away the coating and exposes the underlying dark surface creating tracks. Dust devils have been seen from the ground and from orbit. They have even blown the dust off of the solar panels of the two Rovers on Mars, thereby greatly extending their lives.[7] The twin Rovers were designed to last for 3 months, instead they have lasted more than six years and are still going after over 8 years. The pattern of the tracks have been shown to change every few months.[8] TA study that combined data from the High Resolution Stereo Camera (HRSC) and the Mars Orbiter Camera (MOC) found that some large dust devils on Mars have a diameter of 700 meters and last at least 26 minutes.[9] The image below of Russel Crater shows changes in dust devil tracks over a period of only three months, as documented by HiRISE. Other Dust Devil Tracks are visible in the picture of Frento Vallis.

Craters[edit]

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.[10] The peak is caused by a rebound of the crater floor following the impact.[11] Sometimes craters will display layers. Craters can show us what lies deep under the surface.

Sand Dunes[edit]

Gallery[edit]

References[edit]

  1. ^ Davies, M.E.; Batson, R.M.; Wu, S.S.C. “Geodesy and Cartography” in Kieffer, H.H.; Jakosky, B.M.; Snyder, C.W.; Matthews, M.S., Eds. Mars. University of Arizona Press: Tucson, 1992.
  2. ^ Mars Space Flight Facility (17 March 2004). "Exhumed Crater (Released 17 March 2004)". Arizona State University. Retrieved 19 December 2011. 
  3. ^ a b Lefort, A. et al. 2010. Scalloped terrains in the Peneus and Amphitrites Paterae region of Mars as observed by HiRISE. Icarus: 205. 259-268.
  4. ^ a b http://www.sciencedirect.com/science/journal/00191035
  5. ^ Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY, NY.
  6. ^ Head, J. et al. 2003. Recent ice ages on Mars. Nature:426. 797-802.
  7. ^ "Press Release Images: Spirit". National Aeronautics and Space Administration. 12 April 2007. Retrieved 19 December 2011. 
  8. ^ "Ken Edgett". National Aeronautics and Space Administration. 2001. Retrieved 19 December 2011. 
  9. ^ Reiss, D. et al. 2011. Multitemporal observations of identical active dust devils on Mars with High Resolution Stereo Camera (HRSC) and Mars Orbiter Camera (MOC). Icarus. 215:358-369.
  10. ^ http://www.lpi.usra.edu/publications/slidesets/stones/
  11. ^ Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7. Retrieved 7 March 2011. 

See also[edit]

Mars Quad Map
About this image
MC-27
Noachis