Janssen (Martian Crater)
Janssen Crater is an impact crater in the Arabia quadrangle on Mars at 2.7° N and 322.4° W. and is 154 km in diameter. Its name was approved in 1973, and refers to French astronomer Pierre Janssen. Some close up images of the crater reveal layers in a floor deposit. A picture below show these layers, as well as dark slope streaks. The darker the streak, the younger it is. The layers on the floor of Janssen may have been formed on the bottom of lakes.Fassett, C. and J. Head. 2008. Open-basin lakes on Mars: Implications of valley network lakes for the nature of Noachian hydrology. See also * List of craters on Mars __NOTOC__ This is a list of craters on Mars. Impact craters on Mars larger than exist by the hundreds of thousands, but only about one thousand of them have names. Names are assigned by the International Astronomical Union after petitioning ... References Impact craters on Mars Arabia quadrangle {{Mars-crater-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Arabia Quadrangle
The Arabia 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 Arabia quadrangle (geography), quadrangle is also referred to as MC-12 (Mars Chart-12). The quadrangle contains part of the classic area of Mars known as Arabia Terra, Arabia. It also contains a part of Terra Sabaea and a small part of Meridiani Planum. It lies on the boundary between the young northern plains and the old southern highlands. The quadrangle covers the area from 315° to 360° west longitude and 0° to 30° north latitude. Description The surface of the Arabia quadrangle appears to be very old because it has a high density of craters, but it is not near as high in elevation as typical old surfaces. On Mars the oldest areas contain the most craters; the oldest period is called Noachian after the quadrangle Noachis. The Arabia area contains many buttes and ridges. Some believe th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pierre Janssen
Pierre Jules César Janssen (22 February 1824 – 23 December 1907), usually known as Jules Janssen, was a French astronomer who, along with English scientist Joseph Norman Lockyer, is credited with discovering the gaseous nature of the solar chromosphere, but there is no justification for the conclusion that he deserves credit for the co-discovery of the element helium. Life, work, and interests Janssen was born in Paris (During Bourbon Restoration in France) into a cultivated family. His father, César Antoine Janssen (born in Paris, 1780 – 1860) was a well known clarinettist from Dutch/Belgian descent (his father, Christianus Janssen, emigrated from Walloon Brabant to Paris). His mother Pauline Marie Le Moyne (1789 – 1871) was a daughter of the architect Paul Guillaume Le Moyne. Pierre Janssen studied mathematics and physics at the faculty of sciences. He taught at the Lycée Charlemagne in 1853, and in the school of architecture 1865 – 1871, but his energies were ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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International Astronomical Union
The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded on 28 July 1919 in Brussels, Belgium and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. the Union had 85 national members and 12,734 individual members, spanning 90 countries and territories. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Dark Slope Streaks
Dark slope streaks are narrow, avalanche-like features common on dust-covered slopes in the equatorial regions of Mars.Chuang, F.C.; Beyer, R.A.; Bridges, N.T. (2010). Modification of Martian Slope Streaks by Eolian Processes. ''Icarus,'' 205 154–164. They form in relatively steep terrain, such as along escarpments and impact crater, crater walls.Schorghofer, N.; Aharonson, O.; Khatiwala, S. (2002). Slope Streaks on Mars: Correlations with Surface Properties and the Potential Role of Water. ''Geophys. Res. Lett.,'' 29(23), 2126, . Although first recognized in Viking program, Viking Orbiter images from the late 1970s,Morris, E.C. (1982). Aureole Deposits of the Martian Volcano Olympus Mons. ''J. Geophys. Res.,'' 87(B2), 1164–1178. dark slope streaks were not studied in detail until higher-resolution images from the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) spacecraft became available in the late 1990s and 2000s.Chuang, F.C. ''et al.'' (2007). HiRISE Observ ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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List Of Craters On Mars
__NOTOC__ This is a list of craters on Mars. Impact craters on Mars larger than exist by the hundreds of thousands, but only about one thousand of them have names. Names are assigned by the International Astronomical Union after petitioning by relevant scientists, and in general, only craters that have a significant research interest are given names. Martian craters are named after famous scientists and science fiction authors, or if less than in diameter, after towns on Earth. Craters cannot be named for living people, and names for small craters are rarely intended to commemorate a specific town. Latitude and longitude are given as planetographic coordinates with west longitude. Catalog Martian craters are listed alphabetically on the following partial lists: * List of craters on Mars: A–G * List of craters on Mars: H–N * List of craters on Mars: O–Z Names are grouped into tables for each letter of the alphabet, containing the crater's name (linked if articl ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Impact Craters On Mars
__NOTOC__ This is a list of craters on Mars. Impact craters on Mars larger than exist by the hundreds of thousands, but only about one thousand of them have names. Names are assigned by the International Astronomical Union after petitioning by relevant scientists, and in general, only craters that have a significant research interest are given names. Martian craters are named after famous scientists and science fiction authors, or if less than in diameter, after towns on Earth. Craters cannot be named for living people, and names for small craters are rarely intended to commemorate a specific town. Latitude and longitude are given as planetographic coordinates with west longitude. Catalog Martian craters are listed alphabetically on the following partial lists: * List of craters on Mars: A–G * List of craters on Mars: H–N * List of craters on Mars: O–Z Names are grouped into tables for each letter of the alphabet, containing the crater's name (linked if article e ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |