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Naoshi Fukushima
was a Japanese physicist specializing in the near-Earth space environment. He served as Secretary General of the International Association of Geomagnetism and Aeronomy The International Association of Geomagnetism and Aeronomy (IAGA) is an international scientific association that focuses on the study of terrestrial and planetary magnetism and space physics. IAGA is one of the eight associations of the Interna ... from 1975 to 1983. In 1990 he was awarded the AGU's Waldo E. Smith Medal. He is best known for proving that, under certain conditions, the magnetic field from a field-aligned current and the magnetic field from the associated Pederson current in the ionosphere would exactly cancel at the surface of the Earth. The magnetic equivalence of field-aligned currents with Pederson currents is referred to colloquially as Fukushima's Theorem. 20th-century Japanese scientists 20th-century Japanese astronomers 1925 births 2003 deaths {{japan-astronomer-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Association Of Geomagnetism And Aeronomy
The International Association of Geomagnetism and Aeronomy (IAGA) is an international scientific association that focuses on the study of terrestrial and planetary magnetism and space physics. IAGA is one of the eight associations of the International Union of Geodesy and Geophysics. It is a non-governmental body funded through the subscriptions paid to IUGG by its member countries. IAGA have been responsible for developing and maintaining the International Geomagnetic Reference Field, a reference for the magnetic field of the Earth that was adopted in 1968 and is updated every five years. The most recent version is IGRF-12. History IAGA has a long history and can trace its origins to the Commission for Terrestrial Magnetism and Atmospheric Electricity, part of the World Meteorological Organization originated from the International Meteorological Organization (IMO), which was founded in 1873. At the First IUGG General Assembly (Rome, 1922), the Section de Magnétisme et Electri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Geophysical Union
The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international fields within the Earth and space sciences. The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences; solid-Earth sciences; hydrologic sciences; and space sciences. The organization's headquarters is located on Florida Avenue in Washington, D.C. History The AGU was established in December 1919 by the National Research Council (NRC) to represent the United States in the International Union of Geodesy and Geophysics (IUGG), and its first chairman was William Bowie of the United States Coast and Geodetic Survey (USCGS). For more than 50 years, it operated as an unincorporated affili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waldo E
Waldo may refer to: People * Waldo (given name), a list of people and fictional characters * Waldo (surname), a list of people * Waldo (footballer) (1934-2019), full name Waldo Machado da Silva, Brazilian footballer Places Canada * Waldo, British Columbia, a ghost town United States Inhabited places * Waldo, Alabama, a town * Waldo, Arkansas, a city * Waldo, former name of Sausalito, California, a city * Waldo Junction, California, formerly Waldo, an unincorporated community * Waldo, Florida, a city ** Waldo Historic District, Waldo, Florida * Waldo, Kansas, a small town ** Waldo Township, Russell County, Kansas, the surrounding township * Waldo, Kansas City, Missouri, a city neighborhood * Waldo, Magoffin County, Kentucky * Waldo County, Maine ** Waldo, Maine, a town * Waldo, Missouri, an unincorporated community * Waldo, New Mexico, an unincorporated area * Waldo, Ohio, a village ** Waldo Township, Marion County, Ohio, the surrounding township * Waldo, Oregon, a ghos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birkeland Current
A Birkeland current (also known as field-aligned current) is a set of electrical currents that flow along geomagnetic field lines connecting the Earth's magnetosphere to the Earth's high latitude ionosphere. In the Earth's magnetosphere, the currents are driven by the solar wind and interplanetary magnetic field and by bulk motions of plasma through the magnetosphere (convection indirectly driven by the interplanetary environment). The strength of the Birkeland currents changes with activity in the magnetosphere (e.g. during substorms). Small scale variations in the upward current sheets (downward flowing electrons) accelerate magnetospheric electrons which, when they reach the upper atmosphere, create the Auroras Borealis and Australis. In the high latitude ionosphere (or auroral zones), the Birkeland currents close through the region of the auroral electrojet, which flows perpendicular to the local magnetic field in the ionosphere. The Birkeland currents occur in two pairs of fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pederson Current
Pederson is a patronymic surname meaning "son of Peder". People with the surname Pederson * Barry Pederson, Canadian retired player from National Hockey League * Denis Pederson, Canadian player with the Eisbaren Berlin of the Deutsche Eishockey-Liga; former player National Hockey League * Don Pederson, state senator, Nebraska Legislature * Donald Pederson, American electrical engineer and one of the designers of SPICE * Doug Pederson, American former football quarterback in the NFL * Duane Pederson, coined the terms ''Jesus People'' and ''Jesus Movement'' * Duane C. Pederson, bishop in the Evangelical Lutheran Church in America * Eli Pederson, Wisconsin state assemblyman * Jim Pederson (American football), American football player * Jim Pederson (businessman and politician), American businessman; was Chairman of the Arizona Democratic Party * Joc Pederson, American baseball player * Josh Pederson (born 1997), American football player * Lane Pederson (born 1997), Canadian ice h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionosphere
The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on Earth. History of discovery As early as 1839, the German mathematician and physicist Carl Friedrich Gauss postulated that an electrically conducting region of the atmosphere could account for observed variations of Earth's magnetic field. Sixty years later, Guglielmo Marconi received the first trans-Atlantic radio signal on December 12, 1901, in St. John's, Newfoundland (now in Canada) using a kite-supported antenna for reception. The transmitting station in Poldhu, Cornwall, used a spark-gap transmitter to produce a signal with a freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fukushima's Theorem
In physics, Fukushima's Theorem holds that for all points beneath the ionosphere the magnetic fields from field-aligned currents and their corresponding Pedersen currents exactly cancel. By superposition the total magnetic field at the ground is then equal to the magnetic field from just the ionospheric Hall currents. Fukushima's Theorem holds in any planar or spherical geometry 300px, A sphere with a spherical triangle on it. Spherical geometry is the geometry of the two-dimensional surface of a sphere. In this context the word "sphere" refers only to the 2-dimensional surface and other terms like "ball" or "solid sp ..., provided that the field-aligned currents are perpendicular to the ground, and that the ionospheric conductance is spatially constant. Neither of these conditions holds strongly in the auroral region of the Earth's ionosphere. Journal articles * * Naoshi Fukushima, "Generalized theorem for no ground magnetic effect of vertical currents connected wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1925 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] |
