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NGC 5907
NGC 5907 (also known as NGC 5906, Knife Edge Galaxy, or Splinter Galaxy) is a spiral galaxy located approximately 46.5 million light years from Earth. German-British astronomer William Herschel discovered the galaxy on 5 May 1788. Its most notable features are its large stellar stream and ultraluminous X-ray source. Characteristics NGC 5907 has an anomalously low metallicity and few detectable giant stars, being apparently composed almost entirely of dwarf stars. It is a member of the NGC 5866 Group. NGC 5907 has long been considered a prototypical example of a warped spiral in relative isolation. In 1998, a faint ring structure, likely caused by a disrupted dwarf spheroidal galaxy, was first observed around the galaxy. This challenged the assumption of isolation and suggests the gravitational perturbations induced by the stream progenitor may be the cause for the warp. Then, in 2008, an international team of astronomers announced the presence of an extended double loop tidal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New General Catalogue
The ''New General Catalogue of Nebulae and Clusters of Stars'' (abbreviated NGC) is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxy, galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the ''Index Catalogues'' (abbreviated IC), describing a further 5,386 astronomical objects. Thousands of these objects are best known by their NGC or IC numbers, which remain in widespread use. The NGC expanded and consolidated the cataloguing work of William Herschel, William and Caroline Herschel, and John Herschel's ''General Catalogue of Nebulae and Clusters of Stars''. Objects south of the Celestial sphere, celestial equator are catalogued somewhat less thoroughly, but many were included based on observation by John Herschel or James Dunlop. The NGC contained multiple errors, but attempts to eliminate them were made by the ''Revised New Ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Binary
X-ray binaries are a class of binary stars that are luminous in X-rays. The X-rays are produced by matter falling from one component, called the ''donor'' (usually a relatively common main sequence star), to the other component, called the ''accretor'', which can be a white dwarf, neutron star or black hole. The infalling matter releases gravitational potential energy, up to 30 percent of its rest mass, as X-rays. (Hydrogen fusion releases only about 0.7 percent of rest mass.) The lifetime and the mass-transfer rate in an X-ray binary depends on the evolutionary status of the donor star, the mass ratio between the stellar components, and their orbital separation. An estimated 1041 positrons escape per second from a typical low-mass X-ray binary. Classification X-ray binaries are further subdivided into several (sometimes overlapping) subclasses, that perhaps reflect the underlying physics better. Note that the classification by mass (high, intermediate, low) refers to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubble Space Telescope
The Hubble Space Telescope (HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the Orbiting Solar Observatory, first space telescope, but it is one of the largest and most versatile, renowned as a vital research tool and as a public relations boon for astronomy. The Hubble Space Telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories program, Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible spectrum, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of atmosphere of Earth, Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background lig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Johnstone Stoney
George Johnstone Stoney (15 February 1826 – 5 July 1911) was an Irish physicist known for introducing the term ''electron'' as the "fundamental unit quantity of electricity". He initially named it ''electrolion'' in 1881, and later named it ''electron'' in 1891. He published around 75 scientific papers during his lifetime. Education and employment Stoney was born at Oakley Park, near Birr, County Offaly, in the Irish Midlands, the son of George Stoney (1792–) and Anne Blood (1801–1883). The Stoney family is an old-established Anglo-Irish family. He attended Trinity College Dublin, graduating with a B.A. degree in 1848. From 1848 to 1852 he worked as an astronomy assistant to William Parsons, 3rd Earl of Rosse at Birr Castle, County Offaly, where Parsons had built the world's largest telescope, the 72-inch Leviathan of Parsonstown. Simultaneously Stoney continued to study physics and mathematics and was awarded an M.A. by Trinity College Dublin in 1852. From 185 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 5965
NGC 5965 is a spiral galaxy located in the constellation Draco. It is located at a distance of circa 150 million light years from Earth, which, given its apparent dimensions, means that NGC 5965 is about 260,000 light years across. It was discovered by William Herschel on May 5, 1788. Two supernovae have been observed in NGC 5965: SN 2001cm ( type II, mag. 17.5) and SN 2018cyg (type II, mag. 17). NGC 5965 is seen nearly edge-on, with an inclination of 80 degrees. Dust is seen across the galactic disk, while there is also a red dust lane at the nucleus. The bulge is X-shaped, that suggests that the galaxy is actually barred. NGC 5965 along with another edge-on galaxy, NGC 5746, were the galaxies used to confirm that peanut shaped bulges are associated with the presence of a bar, by spectrographically observing the disturbance caused at the velocity distributions of the galaxies. The galaxy features some level of disk disturbance, like a warp, as the outer part of the disk alon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iota Draconis
Iota Draconis (ι Draconis, abbreviated Iota Dra, ι Dra), also named Edasich , is a star in the northern circumpolar constellation of Draco. A visually unremarkable star of apparent magnitude 3.3, in 2002 it was discovered to have a planet orbiting it (designated Iota Draconis b, later named Hypatia). From parallax measurements, this star is located at a distance of about from the Sun. Nomenclature ''ι Draconis'' ( Latinised to ''Iota Draconis'') is the star's Bayer designation. On discovery the planet was designated Iota Draconis b (or Edasich b). It bore the traditional name ''Edasich'', derived from the Arabic ' of Ulugh Beg and the Dresden Globe, or 'Male hyena' by Kazwini, with ''Eldsich'' being recorded in the ''Century Cyclopedia''. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 5907-starmap
NGC may refer to: Companies * NGC Corporation, the name of US electric company Dynegy, Inc. from 1995 to 1998 * National Gas Company of Trinidad and Tobago, a state-owned natural gas company in Trinidad and Tobago * National Grid plc, a former name of National Grid Electricity Transmission plc, the operator of the British electricity transmission system * Northrop Grumman Corporation, an aerospace and defense conglomerate formed from the merger of Northrop Corporation and Grumman Corporation in 1994 * Numismatic Guaranty Company, a coin certification company in the United States * National Garden Clubs, headquartered in St. Louis, Missouri * Network General Corporation, a defunct networking hardware company Other uses * National Gallery of Canada, an art gallery founded in 1880 in Ottawa, Canada * National Games of China, the national multi-sport event of China * National Geographic (American TV channel), a documentary and reality television channel established in the United State ... [...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] |
Type II Supernova
A Type II supernova or SNII (plural: ''supernovae'') results from the rapid collapse and violent explosion of a massive star. A star must have at least eight times, but no more than 40 to 50 times, the mass of the Sun () to undergo this type of explosion. Type II supernovae are distinguished from other types of supernovae by the presence of hydrogen in their spectra. They are usually observed in the spiral arms of galaxies and in H II regions, but not in elliptical galaxies; those are generally composed of older, low-mass stars, with few of the young, very massive stars necessary to cause a supernova. Stars generate energy by the nuclear fusion of elements. Unlike the Sun, massive stars possess the mass needed to fuse elements that have an atomic mass greater than hydrogen and helium, albeit at increasingly higher temperatures and pressures, causing correspondingly shorter stellar life spans. The degeneracy pressure of electrons and the energy generated by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernova
A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed to form a diffuse nebula. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. The last supernova directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not long after Tycho's Supernova in 1572, both of which were visible to the naked eye. The supernova remnant, remnants of more recent supernovae have been found, and observations of supernovae in other galaxies suggest they occur in the Milky Way on average about three times every century. A supernova in the Milky Way would almost certainly be observable through mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 5879
NGC 5879 is an unbarred spiral galaxy in the constellation Draco. The galaxy was discovered in 1788 by William Herschel. It is a member of the NGC 5866 Group. One supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ... has been observed in NGC 5879: SN 1954C (type unknown, mag. 14.9) was discovered by Paul Wild on 27 September 1954. References External links * * Unbarred spiral galaxies 5879 Draco (constellation) NGC 5866 Group 9753 54117 Astronomical objects discovered in 1788 {{spiral-galaxy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 102
Messier 102 (also known as M102) is a galaxy listed in the Messier Catalogue that cannot be unambiguously identified. Its original discoverer Pierre Méchain retracted his discovery two years after publication and said that it was a duplicate observation of Messier 101.O'Meara, Stephen James. "M102: Mystery Solved", ''Sky and Telescope'', volume 109, number 3, page 78, March 2005 Later historical evidence favors that M102 is actually the galaxy NGC 5866, although other galaxies have been suggested as possible identities. The National Aeronautics and Space Administration (NASA) considers it to be the same as NGC 5866. History The Messier Catalogue was a list of astronomical objects compiled by Charles Messier between 1771 and 1781, in which he briefly described each object and provided their coordinates on the sky. Because Messier was only interested in finding comets, he created this list of non-comet objects that frustrated his hunt for them. Astronomer Pierre Méchain collabor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
