Fredholm (crater)
Fredholm is a small lunar impact crater that is located in the rugged ground to the west of the Mare Crisium. It was named after Swedish mathematician Erik I. Fredholm. It was previously designated Macrobius D. It lies midway between the prominent craters Macrobius to the north and Proclus almost due south. This is a circular, symmetrical formation with a bowl-shaped interior. The inner walls gradually slope down towards the small, central floor, which is less than one quarter the total diameter of the crater. Neatly attached to the northern rim is the smaller Macrobius E. References * * * * * * * * * * * External links LTO-43C3 Proclus— L&PI topographic map In modern mapping, a topographic map or topographic sheet is a type of map characterized by large-scale detail and quantitative representation of relief features, usually using contour lines (connecting points of equal elevation), but histori ... {{Craters on the Moon: C-F Impact craters on t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Apollo 17
Apollo 17 (December 7–19, 1972) was the final mission of NASA's Apollo program, the most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on the Moon, while Command Module Pilot Ronald Evans orbited above. Schmitt was the only professional geologist to land on the Moon; he was selected in place of Joe Engle, as NASA had been under pressure to send a scientist to the Moon. The mission's heavy emphasis on science meant the inclusion of a number of new experiments, including a biological experiment containing five mice that was carried in the command module. Mission planners had two primary goals in deciding on the landing site: to sample lunar highland material older than that at Mare Imbrium and to investigate the possibility of relatively recent volcanic activity. They therefore selected Taurus–Littrow, where formations that had been viewed and pictured from orbi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Erik Ivar Fredholm
Erik Ivar Fredholm (7 April 1866 – 17 August 1927) was a Swedish mathematician whose work on integral equations and operator theory foreshadowed the theory of Hilbert spaces. Biography Fredholm was born in Stockholm in 1866. He obtained his PhD at Uppsala University in 1898, under the supervision of Gösta Mittag-Leffler. He was ''docent'' at Stockholm University from 1898 to 1906 and professor from 1906 until his death. In 1914 he was elected a member of the Royal Swedish Academy of Sciences. Beside his academic career he was recruited to the Swedish Social Insurance Agency when it was founded in 1902. He later served as an actuary at the insurance company Skandia (1904-1927), where his Fredholm equation was used to calculate buyback-prices. From 1911, he was married to Agnes Maria Liljeblad, the secretary of Mittag-Leffler. Mathematical work In , Fredholm introduced and analysed a class of integral equations now called Fredholm equations. His analysis included the c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Crater Fredholm Area
Crater may refer to: Landforms * Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet * Explosion crater, a hole formed in the ground produced by an explosion near or below the surface ** Subsidence crater, a depression from an underground (usually nuclear) explosion * Pit crater, a crater that forms through sinking of the surface and not as a vent for lava * Volcanic crater, a roughly circular depression in the ground caused by volcanic activity **Caldera, a large cauldron-like depression formed following the evacuation of a magma chamber/reservoir **Maar, a type of volcanic crate caused by a phreatic eruption or explosion ** Volcanic crater lake, including a list of lakes that formed in a volcanic or impact crater Music * ''Crater'' (Daniel Menche and Mamiffer album), 2016 * Crater (Fission album), 2004 Places *Crati or Crater, a river of southern Italy * Crater, California, U.S. * Crater (Aden), a district of the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lunar Craters
Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, all of which were formed by impacts. The International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated. History The word ''crater'' was adopted from the Greek word for "vessel" (, a Greek vessel used to mix wine and water). Galileo built his first telescope in late 1609, and turned it to the Moon for the first time on November 30, 1609. He discovered that, contrary to general opinion at that time, the Moon was not a perfect sphere, but had both mountains and cup-like depressions. These were named craters by Johann Hieronymus Schröter (1791), extending its previous use with volcanoes. Robert Hooke in '' Micrographia'' (1665) proposed two hypotheses for lunar crater formation: one, that the craters were caused by projectile bombardment from space, the other, that they were the products of subterranean lunar volcanism. Scientific opinion as to the ori ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Impact Crater
An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Lunar impact craters range from microscopic craters on lunar rocks returned by the Apollo Program and small, simple, bowl-shaped depressions in the lunar regolith to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including the Moon, Mercury, Callisto, Ganymede and most small moons and asteroids. On other planets and moons that experience more active surface geological processes, such as Earth, Venus, Europa, Io and Titan, visible impact craters are less common because they become ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mare Crisium
Mare Crisium (Latin ''crisium'', the "Sea of Crises") is a lunar mare located in the Moon's Crisium basin, just northeast of Mare Tranquillitatis. The basin is of the Pre-Imbrian period, 4.55 to 3.85 billion years ago. Characteristics Mare Crisium is in diameter, and in area. It has a very flat floor, with a ring of wrinkle ridges (''dorsa'') toward its outer boundaries. These are Dorsa Tetyaev, Dorsum Oppel, Dorsum Termier, and Dorsa Harker. The cape-like feature protruding into the southeast of the mare is Promontorium Agarum. On the western rim of the mare is the palimpsest Yerkes, and Lick to the southeast is similar. The crater Picard is located just to the east of Yerkes, and northwest of Picard are the craters Peirce and Swift. The ray system of the crater Proclus overlie the northwestern mare. Mare Anguis can be seen northeast of Mare Crisium. A mass concentration (mascon), or gravitational high, was identified in the center of Mare Crisium from Dopple ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Macrobius (crater)
Macrobius is a prominent lunar impact crater located to the northwest of the Mare Crisium. Its diameter is 63 km. It was named after ancient Roman writer Macrobius. It lies on the southeast edge of the Lacus Bonitatis, a small lunar mare. The somewhat smaller crater Tisserand lies just to the east. The outer wall of Macrobius has a multiply terraced inner surface, with some slumping along the top of the rim. The small satellite crater Macrobius C lies across the western rim, but the wall is otherwise relatively free of significant wear. In the center of the floor is a central mountain complex. There is a low ridge in the western interior, but the remainder of the floor is relatively level. Satellite craters By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Macrobius. The following craters have been renamed by the IAU. * Macrobius A — ''See'' Carmichael. * Macrobius B — ''See ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Proclus (crater)
Proclus is a young lunar impact crater located to the west of the Mare Crisium, on the east shore of the Palus Somni. Its diameter is 27 km. It was named after 5th century Greek mathematician, astronomer and philosopher Proclus. It lies to the south of the prominent, terraced crater Macrobius, and west-northwest of the lava-flooded Yerkes. Description The rim of Proclus is distinctly polygonal in shape, having the shape of a pentagon, and does not rise very far above the surrounding terrain. It has a high albedo, being second only to Aristarchus in brightness. The interior wall displays some slumping, and the floor is uneven with a few small rises from slump blocks. The crater has a notable ray system that extends for a distance of over 600 kilometers. The rays display an asymmetry of form, with the most prominent being rays to the northwest, north-northeast, and northeast. There is an arc with no ejecta to the southwest. These features suggest an impact at a low angl ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown m ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and university textbooks, and English language teaching and learning publications. It also publishes Bibles, runs a bookshop in Cambridge, sells through Amazon, and has a conference venues business in Cambridge at the Pitt Building and the Sir Geoffrey Cass Spo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Jonathan's Space Report
''Jonathan's Space Report'' (JSR) is a newsletter about the Space Age, hosted at Jonathan's Space Page. It is written by Jonathan McDowell, a Center for Astrophysics Harvard & Smithsonian astrophysicist. It is updated as McDowell's schedule permits, but he tries to publish two issues each month. Originally the website was hosted on a Harvard University account, but was moved in late 2003 to a dedicated domain. Started in 1989, the newsletter reports on recent space launches, International Space Station activities and space craft developments. McDowell's report occasionally corrects NASA's official web sites, or provides additional data on classified launches that aren't available elsewhere. Associated projects on the JSR web site are: * A catalog of all known geosynchronous satellites and their current positions * A listing of satellite launch attempts * A cross-reference between catalog number and international designation of artificial satellites McDowell has long campaig ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Sterling Publishing Co
Sterling Publishing Company, Inc. is a publisher of a broad range of subject areas, with multiple imprints and more than 5,000 titles in print. Founded in 1949 by David A. Boehm, Sterling also publishes books for a number of brands, including AARP, Hasbro, Hearst Magazines, and ''USA TODAY'', as well as serves as the North American distributor for domestic and international publishers including: Anova, the Brooklyn Botanic Garden, Carlton Books, Duncan Baird, Guild of Master Craftsmen, the Orion Publishing Group, and Sixth & Spring Books. Sterling also owns and operates two verticals, Lark Crafts and Pixiq. Sterling Publishing is a wholly owned subsidiary of Barnes & Noble, which acquired it in 2003. On January 5, 2012, ''The Wall Street Journal ''The Wall Street Journal'' is an American business-focused, international daily newspaper based in New York City, with international editions also available in Chinese and Japanese. The ''Journal'', along with its Asian editi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |