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Molodensky
Mikhail Sergeevich Molodenskii (russian: Михаил Серге́евич Молоденский, – November 12, 1991) was a Soviet physical geodesist. He was once said to be "probably the only geodesist who would have deserved a Nobel prize". He graduated from Moscow State University (1936), since 1946 he worked for the ''Institute of Earth Physics'' (Институт Физики Земли АН СССР). He created an original theory for determining the figure of the Earth and its gravity field based on measurements done on the topographic surface, built the first Soviet gravimeter, developed a theory of the nutation of Earth. He won the Stalin Prize (1946 and 1951) and the Lenin Prize (1961). His legacy includes the Molodensky transformations, which are commonly used to transform between geodetic datums. His main work (since 1932) was on the geoid and its exterior gravity field or geopotential. His aim was to develop hypothesis-free methods for determining both the gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molodensky Transformations
In geodesy, conversion among different geographic coordinate systems is made necessary by the different geographic coordinate systems in use across the world and over time. Coordinate conversion is composed of a number of different types of conversion: format change of geographic coordinates, conversion of coordinate systems, or transformation to different geodetic datums. Geographic coordinate conversion has applications in cartography, surveying, navigation and geographic information systems. In geodesy, geographic coordinate ''conversion'' is defined as translation among different coordinate formats or map projections all referenced to the same geodetic datum. A geographic coordinate ''transformation'' is a translation among different geodetic datums. Both geographic coordinate conversion and transformation will be considered in this article. This article assumes readers are already familiar with the content in the articles geographic coordinate system and geodetic datum. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a Federation, federal union of Republics of the Soviet Union, fifteen national republics; in practice, both Government of the Soviet Union, its government and Economy of the Soviet Union, its economy were highly Soviet-type economic planning, centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian Soviet Federative Socialist Republic, Russian SFSR. Other major cities included Saint Petersburg, Leningrad (Russian SFSR), Kyiv, Kiev (Ukrainian Soviet Socialist Republic, Ukrainian SSR), Minsk (Byelorussian Soviet Socialist Republic, Byelorussian SSR), Tas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal Height
Normal heights is a type of height above sea level introduced by Mikhail Molodenskii. The normal height H^* (or H^N) of a point is computed as the ratio of a point's geopotential number (i.e. its geopotential difference with that of sea level), by the average, normal gravity computed along the plumb line of the point. (More precisely, along the ellipsoidal normal, averaging over the height range from 0 — on the reference ellipsoid — to H^*; the procedure is thus recursive.) Normal heights are thus dependent upon the reference ellipsoid chosen. The Soviet Union and many other Eastern European countries have chosen a height system based on normal heights, determined by geodetic precise levelling. Normal gravity values are easy to compute and "hypothesis-free", i.e., one does not have to know, as one would for computing orthometric heights, the density of the Earth's crust around the plumb line. The reference surface that normal heights are measured from is called the quasi-g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1991 Deaths
File:1991 Events Collage.png, From left, clockwise: Boris Yeltsin, elected as Russia's first president, waves the new flag of Russia after the 1991 Soviet coup d'état attempt, orchestrated by Soviet hardliners; Mount Pinatubo erupts in the Philippines, making it the second-largest volcanic eruption of the 20th century; MTS Oceanos sinks off the coast of South Africa, but the crew notoriously abandons the vessel before the passengers are rescued; Dissolution of the Soviet Union: The Soviet flag is lowered from the Kremlin for the last time and replaced with the flag of the Russian Federation; The United States and soon-to-be dissolved Soviet Union sign the START I Treaty; A tropical cyclone strikes Bangladesh, killing nearly 140,000 people; Lauda Air Flight 004 crashes after one of its thrust reversers activates during the flight; A United States-led coalition initiates Operation Desert Storm to remove Iraq and Saddam Hussein from Kuwait, 300x300px, thumb rect 0 0 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1909 Births
Nineteen or 19 may refer to: * 19 (number), the natural number following 18 and preceding 20 * one of the years 19 BC, AD 19, 1919, 2019 Films * ''19'' (film), a 2001 Japanese film * ''Nineteen'' (film), a 1987 science fiction film Music * 19 (band), a Japanese pop music duo Albums * ''19'' (Adele album), 2008 * ''19'', a 2003 album by Alsou * ''19'', a 2006 album by Evan Yo * ''19'', a 2018 album by MHD * ''19'', one half of the double album '' 63/19'' by Kool A.D. * '' Number Nineteen'', a 1971 album by American jazz pianist Mal Waldron * ''XIX'' (EP), a 2019 EP by 1the9 Songs * "19" (song), a 1985 song by British musician Paul Hardcastle. * "Nineteen", a song by Bad4Good from the 1992 album ''Refugee'' * "Nineteen", a song by Karma to Burn from the 2001 album ''Almost Heathen''. * "Nineteen" (song), a 2007 song by American singer Billy Ray Cyrus. * "Nineteen", a song by Tegan and Sara from the 2007 album '' The Con''. * "XIX" (song), a 2014 song by Slip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Geodesists
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk (Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Physicists
This list of Russian physicists includes the famous physicists from the Russian Empire, the Soviet Union and the Russian Federation. Alphabetical list __NOTOC__ A * Alexei Abrikosov, discovered how magnetic flux can penetrate a superconductor (the Abrikosov vortex), Nobel Prize winner * Franz Aepinus, related electricity and magnetism, proved the electric nature of pyroelectricity, explained electric polarization and electrostatic induction, invented achromatic microscope * Zhores Alferov, inventor of modern heterotransistor, Nobel Prize winner * Sergey Alekseenko, director of the Kutateladze Institute of Thermophysics, Global Energy Prize recipient * Artem Alikhanian, a prominent researcher of cosmic rays, inventor of wide-gap track spark chamber * Abram Alikhanov, nuclear physicist, a prominent researcher of cosmic rays, built the first nuclear reactors in the USSR, founder of Institute for Theoretical and Experimental Physics (ITEP) * Semen Altshuler, researched ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasi-geoid
Normal heights is a type of height above sea level introduced by Mikhail Molodenskii. The normal height H^* (or H^N) of a point is computed as the ratio of a point's geopotential number (i.e. its geopotential difference with that of sea level), by the average, normal gravity computed along the plumb line of the point. (More precisely, along the ellipsoidal normal, averaging over the height range from 0 — on the reference ellipsoid — to H^*; the procedure is thus recursive.) Normal heights are thus dependent upon the reference ellipsoid chosen. The Soviet Union and many other Eastern European countries have chosen a height system based on normal heights, determined by geodetic precise levelling. Normal gravity values are easy to compute and "hypothesis-free", i.e., one does not have to know, as one would for computing orthometric heights, the density of the Earth's crust around the plumb line. The reference surface that normal heights are measured from is called the quasi-geoid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reference Ellipsoid
An Earth ellipsoid or Earth spheroid is a mathematical figure approximating the Earth's form, used as a reference frame for computations in geodesy, astronomy, and the geosciences. Various different ellipsoids have been used as approximations. It is a spheroid (an ellipsoid of revolution) whose minor axis (shorter diameter), which connects the geographical North Pole and South Pole, is approximately aligned with the Earth's axis of rotation. The ellipsoid is defined by the ''equatorial axis'' (''a'') and the ''polar axis'' (''b''); their radial difference is slightly more than 21 km, or 0.335% of ''a'' (which is not quite 6,400 km). Many methods exist for determination of the axes of an Earth ellipsoid, ranging from meridian arcs up to modern satellite geodesy or the analysis and interconnection of continental geodetic networks. Amongst the different set of data used in national surveys are several of special importance: the Bessel ellipsoid of 1841, the internatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geoid Undulation
The geoid () is the shape that the ocean surface would take under the influence of the gravity of Earth, including gravitational attraction and Earth's rotation, if other influences such as winds and tides were absent. This surface is extended through the continents (such as with very narrow hypothetical canals). According to Gauss, who first described it, it is the "mathematical figure of the Earth", a smooth but irregular surface whose shape results from the uneven distribution of mass within and on the surface of Earth. It can be known only through extensive gravitational measurements and calculations. Despite being an important concept for almost 200 years in the history of geodesy and geophysics, it has been defined to high precision only since advances in satellite geodesy in the late 20th century. All points on a geoid surface have the same geopotential (the sum of gravitational potential energy and centrifugal potential energy). The force of gravity acts everywhere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal Potential
Geopotential is the potential of the Earth's gravity field. For convenience it is often defined as the ''negative'' of the potential energy per unit mass, so that the gravity vector is obtained as the gradient of this potential, without the negation. In addition to the actual potential (the geopotential), a hypothetical normal potential and their difference, the disturbing potential, can also be defined. Concept For geophysical applications, gravity is distinguished from gravitation. Gravity is defined as the resultant force of gravitation and the centrifugal force caused by the Earth's rotation. Likewise, the respective scalar potentials can be added to form an effective potential called the geopotential, W. Global mean sea surface is close to one of the isosurfaces of the geopotential. This ''equipotential surface'', or surface of constant geopotential, is called the ''geoid''. How the gravitational force and the centrifugal force add up to a force orthogonal to the geoid is i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
