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Nelson James Terrell
Nelson James Terrell (August 15, 1923–March 21, 2009) was an US physicist and scientist at Los Alamos National Laboratory. James Terrell worked in relativity and astrophysics. The Terrell rotation, an image distortion of objects travelling near the speed of light, is named after him. Life Nelson James Terrell Jr. was born in Houston, Texas in 1923. James Terrell did his undergraduate studies Rice University. In 1945, he married Anne Elizabeth Pearson. Together, they had a daughter. From 1945 to 1947, the army sent Terrell to Japan. When he came back, he finished his PhD at Rice University in 1950. He worked on nuclear fission and the theory of relativity. He worked as assistant professor at Western Reserve University, and later joined Los Alamos National Laboratory in 1951. Terrell was member of the International Astronomical Union. He died in Los Alamos, New Mexico in 2009. Research In 1957 he started publishing works on length contraction. He discovered that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Houston
Houston ( ) is the List of cities in Texas by population, most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the county seat, seat of Harris County, Texas, Harris County, as well as the principal city of the Greater Houston metropolitan area, the fifth-most populous metropolitan statistical area in the United States and the List of Texas metropolitan areas, second-most populous in Texas after Dallas–Fort Worth metroplex, Dallas–Fort Worth. With a population of 2,314,157 in 2023, Houston is the List of United States cities by population, fourth-most populous city in the United States after New York City, Los Angeles, and Chicago, and the List of North American cities by population, sixth-most populous city in North America. Houston is the southeast anchor of the greater megaregion known as the Texas Triangle. Comprising a land area of , Houston is the List of United S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Astrophysicists
The following is a list of astronomers, astrophysics, astrophysicists and other notable people who have made contributions to the field of astronomy. They may have won major prizes or awards, developed or invented widely used techniques or technologies within astronomy, or are directors of major observatories or heads of space-based telescope projects. Notable astronomers Brief alphabetical list A B C D E F G H I J K L M N O P Q *Adolphe Quetelet (Belgium, 1796–1874) *Ali Qushji (Ottoman Empire, Ottoman, 1403–1474) *M. Shahid Qureshi (Pakistan) R S T U V W Y Z Others who influenced astronomy and astrophysics The following is a list of people who are not astronomers but made a contribution to the field of astronomy and astrophysics. *Hans Bethe (1906–2005), (physicist) *Niels Bohr (1885–1962), (physicist) *Andreas Cellarius (Netherlands, Germany, 1596–1665), (cartographer) *Freeman Dyson (1923–2020), (physicist) *Albert Einstein (1879–1955 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2009 Deaths
This is a list of lists of deaths of notable people, organized by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked below. 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 1986 Earlier years ''Deaths in years earlier than this can usually be found in the main articles of the years.'' See also * Lists of deaths by day * Deaths by year (category) {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1923 Births
In Greece, this year contained only 352 days as 13 days was skipped to achieve the calendrical switch from Julian to Gregorian Calendar. It happened there that Wednesday, 15 February ''(Julian Calendar)'' was followed by Thursday, 1 March ''(Gregorian Calendar).'' Events January–February * January 9, January 5 – Lithuania begins the Klaipėda Revolt to annex the Klaipėda Region (Memel Territory). * January 11 – Despite strong British protests, troops from France and Belgium Occupation of the Ruhr, occupy the Ruhr area, to force Germany to make reparation payments. * January 17 (or 9) – First flight of the first rotorcraft, Juan de la Cierva's Cierva C.4 autogyro, in Spain. (It is first demonstrated to the military on January 31.) * February 5 – Australian cricketer Bill Ponsford makes 429 runs to break the world record for the highest first-class cricket score for the first time in his third match at this level, at Melbourne Cricket Ground, giving the Victor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vela (satellite)
Vela was the name of a group of reconnaissance satellites developed as the Vela Hotel element of Project Vela by the United States to detect nuclear detonations and monitor Soviet Union compliance with the 1963 Partial Test Ban Treaty. Vela started out as a small budget research program in 1959. It ended 26 years later as a successful, cost-effective military space system, which also provided scientific data on natural sources of space radiation. In the 1970s, the nuclear detection mission was taken over by the Defense Support Program (DSP) satellites. In the late 1980s, it was augmented by the Navstar Global Positioning System (GPS) satellites. The program is now called the Integrated Operational NuDet (Nuclear Detonation) Detection System (Nuclear MASINT#Space-based Nuclear Energy Detection, IONDS). Deployment Twelve satellites were built, six of the Vela Hotel design and six of the Advanced Vela design. The Vela Hotel series was to detect nuclear tests in space, while the Adv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Hole
A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. The boundary (topology), boundary of no escape is called the event horizon. A black hole has a great effect on the fate and circumstances of an object crossing it, but has no locally detectable features according to general relativity. In many ways, a black hole acts like an ideal black body, as it reflects no light. Quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with thermal radiation, the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is of the Orders of magnitude (temperature), order of billionths of a kelvin for stellar black holes, making it essentially impossible to observe directly. Objects whose gravitational fields are too strong for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a galactic X-ray source in the constellation Cygnus and was the first such source widely accepted to be a black hole. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources detectable from Earth, producing a peak X-ray flux density of (). It remains among the most studied astronomical objects in its class. The compact object is now estimated to have a mass about 21.2 times the mass of the Sun and has been shown to be too small to be any known kind of normal star or other likely object besides a black hole. If so, the radius of its event horizon has "as upper bound to the linear dimension of the source region" of occasional X-ray bursts lasting only for about 1 ms. Cygnus X-1 belongs to a high-mass X-ray binary system, located about 7,000 light-years away, that includes a blue supergiant variable star designated HDE 226868, which it orbits at about 0.2 AU, or 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasar
A quasar ( ) is an extremely Luminosity, luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by accretion onto a supermassive black hole with a mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous Accretion disk, accretion disc. Gas in the disc falling towards the black hole heats up and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosity, luminosities thousands of times greater than that of a galaxy such as the Milky Way. Quasars are usually categorized as a subclass of the more general category of AGN. The redshifts of quasars are of Expansion of the universe, cosmological origin. The term originated as a Contraction (grammar), contraction of "quasi-stellar ''[star-like]'' radio source"—because they were first identified during the 1950s as sources of radio-wave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Special Relativity
In physics, the special theory of relativity, or special relativity for short, is a scientific theory of the relationship between Spacetime, space and time. In Albert Einstein's 1905 paper, Annus Mirabilis papers#Special relativity, "On the Electrodynamics of Moving Bodies", the theory is presented as being based on just Postulates of special relativity, two postulates: # The laws of physics are Invariant (physics), invariant (identical) in all Inertial frame of reference, inertial frames of reference (that is, Frame of reference, frames of reference with no acceleration). This is known as the principle of relativity. # The speed of light in vacuum is the same for all observers, regardless of the motion of light source or observer. This is known as the principle of light constancy, or the principle of light speed invariance. The first postulate was first formulated by Galileo Galilei (see ''Galilean invariance''). Background Special relativity builds upon important physics ide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Length Contraction
Length contraction is the phenomenon that a moving object's length is measured to be shorter than its proper length, which is the length as measured in the object's own rest frame. It is also known as Lorentz contraction or Lorentz–FitzGerald contraction (after Hendrik Lorentz and George Francis FitzGerald) and is usually only noticeable at a substantial fraction of the speed of light. Length contraction is only in the direction in which the body is travelling. For standard objects, this effect is negligible at everyday speeds, and can be ignored for all regular purposes, only becoming significant as the object approaches the speed of light relative to the observer. History Length contraction was postulated by George Francis FitzGerald, George FitzGerald (1889) and Hendrik Antoon Lorentz (1892) to explain the negative outcome of the Michelson–Morley experiment and to rescue the hypothesis of the stationary aether (Lorentz ether theory#Length contraction, Lorentz–FitzGerald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
