{{Short description|Map of Mars}} {{Infobox feature on celestial object |name = Casius [[quadrangle (geography)|quadrangle]] |image = USGS-Mars-MC-6-CasiusRegion-mola2.png |caption = Elevation map of Casius quadrangle from [[Mars Orbiter Laser Altimeter]] (MOLA) data. |coordinates = {{coord|47.5|N|270|W|globe:mars_type:landmark|display=inline,title}} }}
The '''Casius quadrangle''' is one of a series of [[list of quadrangles on Mars|30 quadrangle maps of Mars]] used by the [[United States Geological Survey]] (USGS) [[Astrogeology Research Program]]. The [[quadrangle (geography)|quadrangle]] is located in the north-central portion of Mars' eastern hemisphere and covers 60° to 120° east longitude (240° to 300° west longitude) and 30° to 65° north latitude. The quadrangle uses a [[Lambert conformal conic projection]] at a nominal scale of 1:5,000,000 (1:5M). The Casius quadrangle is also referred to as MC-6 (Mars Chart-6).<ref>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.</ref> Casius quadrangle contains part of [[Utopia Planitia]] and a small part of [[Terra Sabaea]]. The southern and northern borders of the Casius quadrangle are approximately 3,065 km and 1,500 km wide, respectively. The north to south distance is about 2,050 km (slightly less than the length of Greenland).<ref>Distances calculated using NASA World Wind measuring tool. http://worldwind.arc.nasa.gov/ {{Webarchive|url=https://web.archive.org/web/20180106075159/http://worldwind.arc.nasa.gov/ |date=2018-01-06 }}.</ref> The quadrangle covers an approximate area of 4.9 million square km, or a little over 3% of Mars' surface area.<ref>Approximated by integrating latitudinal strips with an area of R^2 (L1-L2)(cos(A)dA) from 30° to 65° latitude; where R = 3889 km, A is latitude, and angles expressed in radians. See: https://stackoverflow.com/questions/1340223/calculating-area-enclosed-by-arbitrary-polygon-on-earths-surface.</ref>
==Origin of name== Casius is the name of a [[classical albedo features on Mars|telescopic albedo feature]] located at 40° N and 100° E on Mars. The feature was named by [[Giovanni Schiaparelli|Schiaparelli]] in 1888 after [[Ras Kouroun|Mt Casius]] in Egypt, famous in antiquity for the nearby [[Lake Bardawil|coastal marshes]] in which whole armies were reputed to have drowned. The name was approved by the [[International Astronomical Union]] (IAU) in 1958.<ref>USGS Gazetteer of Planetary Nomenclature. Mars. https://planetarynames.wr.usgs.gov/.</ref>
==Physiography and geology== The high latitude Casius quadrangle bears several features that are believed to indicate the presence of ground ice.{{Citation needed|date=January 2026}} [[Patterned ground]] is one such feature. Usually, polygonal shapes are found poleward of 55 degrees latitude.<ref>Mangold, N. 2005. High latitude patterned grounds on Mars: Classification, distribution and climatic control. Icarus. 174-336-359.</ref> Other features associated with ground ice are [[scalloped topography]],<ref>{{Cite web |url=http://hiroc.lpl.arizona.edu/images/PSP/diafotizo.php?ID=PSP_002296_1215 |title=HiRISE | Scalloped Topography in Peneus Patera Crater |access-date=2009-05-29 |archive-date=2016-10-01 |archive-url=https://web.archive.org/web/20161001224222/http://hiroc.lpl.arizona.edu/images/PSP/diafotizo.php?ID=PSP_002296_1215 |url-status=dead }}</ref> [[Ring mold crater]]s, and [[concentric crater fill]].
==See also== {{div col|colwidth=30em}} * [[Climate of Mars]] * [[Geology of Mars]] * [[Patterned ground]] * [[Water on Mars]] {{div col end}}
==References== {{reflist|colwidth=30em}}
== External links == {{commons category|Casius quadrangle}} * [https://www.youtube.com/watch?v=_sUUKcZaTgA Martian Ice - Jim Secosky - 16th Annual International Mars Society Convention] * [https://www.youtube.com/watch?v=kpnTh3qlObk T. Gordon Wasilewski - Water on Mars - 20th Annual International Mars Society Convention]. Describes how to get water from ice in the ground
{{Mars quadrangle layout}} {{Mars}} {{Portal bar|Solar System}}
[[Category:Casius quadrangle| ]] [[Category:Mars]]