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IC 4182
IC 4182 is a Magellanic spiral galaxy in the constellation Canes Venatici. The galaxy lies about 14 million light years away from Earth, which means, given its apparent dimensions, that IC 4182 is approximately 28,000 light years across. It was discovered by German astronomer Max Wolf on 21 March 1903. IC 4182 is seen nearly face-on. It has a low surface brightness disk with patch of star formation and no spiral pattern. The galaxy is close enough for its brightest stars to be resolvable through large telescopes, having a photometric blue filter apparent magnitude of 19.2, and a visual magnitude of around 20 for the brightest blue stars and around 21 for the brightest red stars. The density of ultraviolet sources decreases monotonically with radius. IC 4182 has been the home of one supernova, SN 1937C ( type Ia, mag. 8.4). Fritz Zwicky discovered the supernova, which was located 30 arcseconds north and 40 arcseconds east of the nucleus, on 24 August 1937. The supernova was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index 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 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 and Caroline Herschel, and John Herschel's '' General Catalogue of Nebulae and Clusters of Stars''. Objects south of the 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 General Catalogue'' (RNGC) by Jack W. Sule ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz Zwicky
Fritz Zwicky (; ; February 14, 1898 – February 8, 1974) was a Swiss astronomer. He worked most of his life at the California Institute of Technology in the United States of America, where he made many important contributions in theoretical and observational astronomy. In 1933, Zwicky was the first to use the virial theorem to postulate the existence of unseen dark matter, describing it as "'". From p 125: ''"Um, wie beobachtet, einen mittleren Dopplereffekt von 1000 km/sek oder mehr zu erhalten, müsste also die mittlere Dichte im Comasystem mindestens 400 mal grösser sein als die auf Grund von Beobachtungen an leuchtender Materie abgeleitete. Falls sich dies bewahrheiten sollte, würde sich also das überraschende Resultat ergeben, dass dunkle Materie in sehr viel grösserer Dichte vorhanden ist als leuchtende Materie."'' (In order to obtain an average Doppler effect of 1000 km/s or more, as observed, the average density in the Coma system would thus have to be at least 40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MCG Objects
The Melbourne Cricket Ground (MCG), also known locally as the 'G, is a sports stadium located in Yarra Park, Melbourne, Victoria. Founded and managed by the Melbourne Cricket Club, it is the largest stadium in the Southern Hemisphere, the List of stadiums by capacity, eleventh-largest stadium globally, and List of cricket grounds by capacity, the second-largest cricket stadium by capacity. The MCG is within walking distance of the Melbourne City Centre, Melbourne CBD and is served by Richmond railway station, Melbourne, Richmond and Jolimont railway station, Jolimont railway stations, as well as the Melbourne tram route 70, route 70, Melbourne tram route 75, 75 and Melbourne tram route 48, 48 trams. It is adjacent to Melbourne Park and is an integral part of the Melbourne Sports and Entertainment Precinct. Since it was built in 1853, the MCG has undergone numerous renovations. It served as the main stadium for the 1956 Summer Olympics and the 2006 Commonwealth Games, as well a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UGC Objects
UGC may refer to: Organisations * Canadian Geophysical Union, official abbreviation in French (Union géophysique canadienne) * UGC (cinema operator), a European cinema chain, formerly Union Générale Cinématographique * UGC Fox Distribution, a former French-American film production company formed in 1995 * Union Graduate College, Schenectady, New York * United Grain Company, a Russian grain trading company based in Moscow * University Grants Commission (other) * University Grants Committee (other) * UnitedGlobalCom, former name of the cable TV operator Liberty Global * UnderGround Crips, an African American street gang mainly from Los Angeles, California Science and technology * Universal gravitational constant G, in physics * Uppsala General Catalogue, an astronomical catalogue of galaxies * UGC, a codon for cysteine * Unique games conjecture, a conjecture in computational complexity Other * User-generated content User-generated content (UGC), a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IC Objects
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 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 and Caroline Herschel, and John Herschel's ''General Catalogue of Nebulae and Clusters of Stars''. Objects south of the 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 General Catalogue'' (RNGC) by Jack W. Sulenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unbarred Spiral Galaxies
A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars. Bars are found in about two thirds of all spiral galaxies in the local universe, and generally affect both the motions of stars and interstellar gas within spiral galaxies and can affect spiral arms as well. The Milky Way Galaxy, where the Solar System is located, is classified as a barred spiral galaxy. Edwin Hubble classified spiral galaxies of this type as "SB" (spiral, barred) in his Hubble sequence and arranged them into sub-categories based on how open the arms of the spiral are. SBa types feature tightly bound arms, while SBc types are at the other extreme and have loosely bound arms. SBb-type galaxies lie in between the two. SB0 is a barred lenticular galaxy. A new type, SBm, was subsequently created to describe somewhat Barred irregular galaxy, irregular barred spirals, such as the Magellanic Clouds, which were once classified as irregular galaxies, but have since been found t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magellanic Spiral Galaxies
A Magellanic spiral galaxy is a spiral galaxy with only one spiral arm. Magellanic spiral galaxies are classified as the type Sm (with sub-categories SAm, SBm, SABm); the prototype galaxy and namesake for Magellanic spirals is the Large Magellanic Cloud, an SBm galaxy. They are usually smaller dwarf galaxies and can be considered to be intermediate between dwarf spiral galaxies and irregular galaxies. Magellanic spirals SAm galaxies are a type of unbarred spiral galaxy, while SBm are a type of barred spiral galaxy. Linda S. Sparke, John Sill Gallagher, ''Galaxies in the Universe: An Introduction'', 2ed., Cambridge University Press, 2007, SABm are a type of intermediate spiral galaxy. Type ''Sm'' and ''Im'' galaxies have also been categorized as irregular galaxies with some structure (type Irr-1). Sm galaxies are typically disrupted and asymmetric. dSm galaxies are dwarf spiral galaxies or dwarf irregular galaxies, depending on categorization scheme. The Magellanic spiral classi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 5033
NGC 5033 is an inclined spiral galaxy located in the constellation Canes Venatici. Its velocity with respect to the cosmic microwave background is , which corresponds to a Hubble distance of . Additionally, 25 ''non-redshift'' measurements give a similar distance of . It was discovered by German-British astronomer William Herschel on 1 May 1785. NGC 5033 has a very bright nucleus and a relatively faint disk. Significant warping is visible in the southern half of the disk. The galaxy's relatively large angular size and relatively high surface brightness make it an object that can be viewed and imaged by amateur astronomers. The galaxy's location relatively near Earth and its active galactic nucleus make it a commonly studied object for professional astronomers. Supernovae Four supernovae have been observed in NGC 5033: * SN 1950C (type unknown, mag. 18.2) was discovered by Fritz Zwicky on 14 May 1950. * SN 1985L ( Type II, mag. 12.5) was discovered by Natalya Metlova on 13 J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 5005
NGC 5005, also known as Caldwell 29, is an inclined spiral galaxy in the constellation Canes Venatici. It was discovered by German-British astronomer William Herschel on 1 May 1785. The galaxy has a relatively bright nucleus and a bright disk that contains multiple dust lanes. The galaxy's high surface brightness makes it an object that is visible to amateur astronomers using large amateur telescopes. Distance measurements for NGC 5005 vary from 13.7 megaparsecs (45 million light-years) to 34.6 megaparsecs (113 million light-years), averaging about 20 megaparsecs (65 million light-years). Supernova One supernova has been observed in NGC 5005: SN 1996ai ( Type Ia, mag. 14.5) was discovered by Claudio Bottari on 16 June 1996. Nucleus NGC 5005 contains a low ionization nuclear emission region (LINER) nucleus. LINER nuclei contain weakly ionized gas. The power source for the LINER emission has been debated extensively, with some researchers suggesting that LINERs are power ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyons Groups Of Galaxies
Lyons Groups of Galaxies (or LGG) is an astronomical catalog of nearby groups of galaxies complete to a limiting apparent magnitude B0=14.0 with a recession velocity smaller than 5,500 km/s. The catalogue was obtained from the Lyon-Meudon Extragalactic Database. Two methods were used in group construction: a percolation method derived from Huchra and Geller and a hierarchical method initiated by R. Brent Tully. The catalog is a synthesized version of the two results. The LGG includes 485 groups and 3,933 member galaxies. See also * Abell catalogue * New General Catalogue * Messier Catalogue The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ' (''Catalogue of Nebulae and Star Clusters''). Because Messier was interested only in finding comets, he created a list of thos ... References External links LGG description at CDSFull LGG list of records at CDSADS: General study of group membership. II - D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M94 Group
The M94 Group (Canes I Group or Canes Venatici I Group) is a loose, extended group of galaxies located about 13 million light-years away in the constellations Canes Venatici and Coma Berenices. The group is one of many groups that lies within the Virgo Supercluster (i.e. the Local Supercluster) and one of the closest groups to the Local Group. Although the galaxies in this cluster appear to be from a single large cloud-like structure, many of the galaxies within the group are only weakly gravitationally bound, and some have not yet formed stable orbits around the center of this group. Instead, most of the galaxies in this group appear to be moving with the expansion of the universe. Members The table below lists galaxies that have been consistently identified as group members in the Nearby Galaxies Catalog, the Lyons Groups of Galaxies (LGG) Catalog, and the three group lists created from the Nearby Optical Galaxy sample of Giuricin et al. Additionally, NGC 4105 and DDO 16 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubble Constant
Hubble's law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther a galaxy is from the Earth, the faster it moves away. A galaxy's recessional velocity is typically determined by measuring its redshift, a shift in the frequency of light emitted by the galaxy. The discovery of Hubble's law is attributed to work published by Edwin Hubble in 1929, but the notion of the universe expanding at a calculable rate was first derived from general relativity equations in 1922 by Alexander Friedmann. The Friedmann equations showed the universe might be expanding, and presented the expansion speed if that were the case. Before Hubble, astronomer Carl Wilhelm Wirtz had, in 1922 and 1924, deduced with his own data that galaxies that appeared smaller and dimmer had larger redshifts and thus that more distant galaxies recede faster from the observer. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
