View source for Astronomy:Wislicenus (crater)

{{Short description|Crater on Mars}}
{{Infobox crater data
| titlecolor  = #FA8072
| title       = Wislicenus
| image       = Wislicenus crater 618A01 618A22.jpg
| caption     = [[Engineering:Viking program|Viking Orbiter 1]] mosaic with Wislicenus at center
| coordinate_title = [[Astronomy:Mars#Geography|Coordinates]]
| globe       = Mars
| coordinates = {{coord|18.4|S|348.6|W|globe:mars_type:landmark|display=inline,title}}
| diameter    = {{cvt|140.15|km}}
| eponym      = Walter Wislicenus, German astronomer (1859–1905)
}}

'''Wislicenus''' is an [[Astronomy:Impact crater|impact crater]] on [[Astronomy:Mars|Mars]], located in the [[Astronomy:Sinus Sabaeus quadrangle|Sinus Sabaeus quadrangle]] at 18.4° south latitude and 348.6° west longitude. It measures approximately {{cvt|140.15|km}} in diameter and was named after German astronomer Walter Wislicenus (1859–1905). The name was adopted by the [[Organization:International Astronomical Union|IAU]] in 1973.<ref>{{GPN|6565}}</ref>

== Layers ==
[[File:Wislicenus Crater Floor.JPG|200px|left|thumb|Visible layers on floor of ''Wislicenus'' due to erosion (HiRISE)]]

Wislicenus crater contains layers, also called strata. Many places on Mars show rocks arranged in layers. Sometimes the layers are of different colors. Light-toned rocks on Mars have been associated with hydrated minerals like sulfates. The [[Astronomy:Mars rover|Mars rover]] ''[[Engineering:Opportunity (rover)|Opportunity]]'' examined such layers close-up with several instruments. Some layers are probably made up of fine particles because they seem to break up into find dust. Other layers break up into large boulders so they are probably much harder. [[Earth:Basalt|Basalt]], a volcanic rock, is thought to in the layers that form boulders. Basalt has been identified on Mars in many places. Instruments on orbiting spacecraft have detected clay (also called phyllosilicates) in some layers. Scientists are excited about finding hydrated minerals such as sulfates and clays on Mars because they are usually formed in the presence of water.<ref>{{Cite web|title=Target Zone: Nilosyrtis? {{!}} Mars Odyssey Mission THEMIS|url=http://themis.mars.asu.edu/feature/49|access-date=2021-06-26|website=themis.mars.asu.edu}}</ref> Areas that contain clays and/or other hydrated minerals would be good places to look for evidence of life.<ref>{{Cite web|title=HiRISE {{!}} Craters and Valleys in the Elysium Fossae (PSP_004046_2080)|url=https://hirise.lpl.arizona.edu/PSP_004046_2080|access-date=2021-06-26|website=hirise.lpl.arizona.edu}}</ref>

Rock can form layers in a variety of ways. Volcanoes, wind, or water can produce layers.<ref>{{Cite web|title=HiRISE {{!}} High Resolution Imaging Science Experiment|url=https://hirise.lpl.arizona.edu/?PSP_008437_1750|access-date=2021-06-26|website=hirise.lpl.arizona.edu}}</ref> However, the presence of hydrated minerals in Wislicenus crater is strong evidence for the involvement of water, perhaps in a lake. Many craters once contained lakes.<ref>Cabrol, N. and E. Grin. 2001. "The Evolution of Lacustrine Environments on Mars: Is Mars Only Hydrologically Dormant?" ''Icarus'': 149, 291-328.</ref><ref>Fassett, C. and J. Head. 2008. "Open-basin lakes on Mars: Distribution and implications for Noachian surface and subsurface hydrology". ''Icarus'': 198, 37–56.</ref>

[[File:Wikiwislicenus.jpg|thumb|Western side of Wislicenus as seen by CTX camera on [[Astronomy:Mars Reconnaissance Orbiter|MRO]]]]

== See also ==
{{cmn|colwidth=30em|
* [[Astronomy:Climate of Mars|Climate of Mars]]
* HiRISE
* [[Earth:Hydrothermal circulation|Hydrothermal circulation]]
* [[Astronomy:Impact event|Impact event]]
* [[Astronomy:Lakes on Mars|Lakes on Mars]]
* [[Astronomy:List of craters on Mars|List of craters on Mars]]
* [[Chemistry:Ore genesis|Ore genesis]]
* [[Astronomy:Ore resources on Mars|Ore resources on Mars]]
* [[Astronomy:Planetary nomenclature|Planetary nomenclature]]
* [[Astronomy:Water on Mars|Water on Mars]]
}}

== References ==
{{reflist}}

{{Geography of Mars}}

{{DEFAULTSORT:Wislicenus (Crater)}}
[[Category:Sinus Sabaeus quadrangle]]
[[Category:Impact craters on Mars]]

{{Sourceattribution|Wislicenus (crater)}}