Wislicenus (crater)
Quadrangle map of Sinus Sabaeus labeled with major features. Colored rectangles represent image footprints of Mars Global Surveyor.
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| Planet | Mars |
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| Coordinates | 18°24′S 348°36′W / 18.4°S 348.6°WCoordinates: 18°24′S 348°36′W / 18.4°S 348.6°W |
| Diameter | 139 km |
| Eponym | Walter Wislicenus, a German astronomer (1859-1905) |
Wislicenus Crater is an impact crater in the Sinus Sabaeus quadrangle of Mars at 18.4° south latitude and 348.6° west longitude. It is about 139 km in diameter and was named after Walter Wislicenus, a German astronomer (1859–1905).
Western side of Wislicenus Crater as seen by CTX camera (on Mars Reconnaissance Orbiter).
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 hydraded minerals like sulfates. The Mars 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. 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. Places that contain clays and/or other hydrated minerals would be good places to look for evidence of life.
Rock can form layers in a variety of ways. Volcanoes, wind, or water can produce layers.
The density of impact craters is used to determine the surface ages of Mars and other solar system bodies. The older the surface, the more craters present. Crater shapes can reveal the presence of ground ice.
The area around craters may be rich in minerals. On Mars, heat from the impact melts ice in the ground. Water from the melting ice dissolves minerals, and then deposits them in cracks or faults that were produced with the impact. This process, called hydrothermal alteration, is a major way in which ore deposits are produced. The area around Martian craters may be rich in useful ores for the future colonization of Mars. Studies on the earth have documented that cracks are produced and that secondary minerals veins are deposited in the cracks. Images from satellites orbiting Mars have detected cracks near impact craters. Great amounts of heat are produced during impacts. The area around a large impact may take hundreds of thousands of years to cool.
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