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NGC 4478
NGC 4478 is an elliptical galaxy located about 50 million light-years away in the constellation Virgo. NGC 4478 was discovered by astronomer William Herschel on April 12, 1784. NGC 4478 is a member of the Virgo Cluster. Nuclear disk Hubble images indicate that NGC 4478 has a central nuclear disk. Metallicity In NGC 4478, the central regions of the galaxy are high in metals while having less overabundance of the element iron than the main body. In contrast, the outer regions of the galaxy are low in metals while having a high overabundance in iron. Globular clusters NGC 4478 has a typical sub-population of metal-poor globular clusters. However, it has a lack of metal-rich clusters. The lack of metal-rich clusters in other galaxies is usually attributed to accretion, or mergers with other galaxies. The only other known elliptical that has been shown to have a domination of metal-poor globular clusters is the giant galaxy NGC 4874 which is located in the center of the Coma Clus ... [...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 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. Sulent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4874
NGC 4874 is a giant elliptical galaxy. It was discovered by the British astronomer Frederick William Herschel I in 1785, who catalogued it as a bright patch of nebulous feature. The second-brightest galaxy within the northern Coma Cluster, it is located at a distance of 109 megaparsecs (350,000,000 light-years) from Earth. Characteristics The galaxy is surrounded by an immense stellar halo that extends up to one million light-years in diameter. It is also enveloped by a huge cloud of interstellar medium that is currently being heated by action of infalling material from its central supermassive black hole. A jet of highly energetic plasma extends out to 1,700 light-years from its center. The galaxy has 18,700 ± 2,260 globular clusters. See also * List of largest galaxies This is a list of largest galaxies known, sorted by order of increasing major axis diameters. The unit of measurement used is the light-year (approximately 9.46 kilometers). Overview Galaxies are vast co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UGC Objects
UGC may refer to: 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 In computational complexity theory, the unique games conjecture (often referred to as UGC) is a conjecture made by Subhash Khot in 2002. The conjecture postulates that the problem of determining the approximate ''value'' of a certain type of gam ..., a conjecture in computational complexity Organisations * 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 * Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Principal Galaxies Catalogue Objects
Principal may refer to: Title or rank * Principal (academia), the chief executive of a university ** Principal (education), the office holder/ or boss in any school * Principal (civil service) or principal officer, the senior management level in the UK Civil Service * Principal dancer, the top rank in ballet * Principal (music), the top rank in an orchestra Law * Principal (commercial law), the person who authorizes an agent ** Principal (architecture), licensed professional(s) with ownership of the firm * Principal (criminal law), the primary actor in a criminal offense * Principal (Catholic Church), an honorific used in the See of Lisbon Places * Principal, Cape Verde, a village * Principal, Ecuador, a parish Media * ''The Principal'' (TV series), a 2015 Australian drama series * ''The Principal'', a 1987 action film * Principal (music), the lead musician in a section of an orchestra * Principal photography, the first phase of movie production * "The Principal", a song on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 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] |
Elliptical Galaxies
An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work ''The Realm of the Nebulae'', with their intermediate scale disks, a subset of the "early-type" galaxy population. Most elliptical galaxies are composed of older, low-mass stars, with a sparse interstellar medium and minimal star formation activity, and they tend to be surrounded by large numbers of globular clusters. Elliptical galaxies are believed to make up approximately 10–15% of galaxies in the Virgo Supercluster, and they are not the dominant type of galaxy in the universe overall. They are preferentially found close to the centers of galaxy clusters. Elliptical galaxies range in size from dwarf ellipticals with tens of millions of stars, to supergiants of over one hundred trillion stars that dominate their galaxy clusters. Originally, Ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 4458
NGC 4458 is an elliptical galaxy located about 54 million light-years away in the constellation of Virgo. It was discovered by astronomer William Herschel on April 12, 1784. NGC 4458 is a member of Markarian's Chain which is part of the Virgo Cluster. It is in a pair with the galaxy NGC 4461. NGC 4458 and NGC 4461 are interacting with each other. NGC 4458 may have a supermassive black hole with an estimated mass of 200 million Suns ( M☉). Nuclear disk NGC 4458 has an edge-on nuclear disk which is estimated to be about 6 billion years old. The disk likely formed from the merger of a gas-rich galaxy and has been found to have "similar properties to the decoupled cores of bright ellipticals". L. Morelli, C. Halliday, E. M. Corsini, A. Pizzella, D. Thomas, R. P. Saglia, R. L. Davies, R. Bender, M. Birkinshaw, F. Bertola, Nuclear stellar discs in low-luminosity elliptical galaxies: NGC 4458 and 4478, Monthly Notices of the Royal Astronomical Society, Volume 354, Issue 3, Nov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of NGC Objects (4001–5000)
This is a list of NGC objects 4001–5000 from the New General Catalogue (NGC). The astronomical catalogue is composed mainly of star clusters, nebulae, and galaxies. Other objects in the catalogue can be found in the other subpages of the list of NGC objects. The constellation information in these tables is taken from ''The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters by Jjiko. L. E. Dreyer'', which was accessed using the "VizieR Service". Galaxy types are identified using the ''NASA/IPAC Extragalactic Database''. The other data of these tables are from the SIMBAD Astronomical Database unless otherwise stated. 4001–4100 4101–4200 4201-4300 4301–4400 4401–4500 4501–4600 4601–4700 4701–4800 4801–4900 4901–5000 See also * Lists of astronomical objects This is a list of lists, grouped by type of astronomical object. Solar System * List of Solar System objects * List of gravitationally rounded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parsec
The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (au), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, and is defined as the distance at which 1 au subtends an angle of one arcsecond ( of a degree). This corresponds to astronomical units, i.e. 1\, \mathrm = 1/\tan \left( \ \mathrm \right)\, \mathrm. The nearest star, Proxima Centauri, is about from the Sun. Most stars visible to the naked eye are within a few hundred parsecs of the Sun, with the most distant at a few thousand. The word ''parsec'' is a portmanteau of "parallax of one second" and was coined by the British astronomer Herbert Hall Turner in 1913 to make calculations of astronomical distances from only raw observational data easy for astronomers. Partly for this reason, it is the unit preferred in astronomy and astrophysics, though the light-year remains prominent in popular s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-years
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 (one million million, or billion in long scale). As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in a vacuum in one Julian year (365.25 days). Because it includes the time-measurement word "year", the term ''light-year'' is sometimes misinterpreted as a unit of time. The ''light-year'' is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist contexts and popular science publications. The unit most commonly used in professional astronomy is the parsec (symbol: pc, about 3.26 light-years) which derives from astrometry; it is the distance at which one astronomical unit subtends an angle of one second of arc. Defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 87
Messier 87 (also known as Virgo A or NGC 4486, generally abbreviated to M87) is a supergiant elliptical galaxy with several trillion stars in the constellation Virgo. One of the largest and most massive galaxies in the local universe, it has a large population of globular clusters — about 15,000 compared with the 150–200 orbiting the Milky Way — and a jet of energetic plasma that originates at the core and extends at least , traveling at a relativistic speed. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers. The French astronomer Charles Messier discovered M87 in 1781, and cataloged it as a nebula. M87 is about from Earth and is the second-brightest galaxy within the northern Virgo Cluster, having many satellite galaxies. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical gala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coma Cluster
The Coma Cluster (Abell 1656) is a large galaxy cluster, cluster of galaxies that contains over 1,000 identified galaxies. Along with the Leo Cluster (Abell 1367), it is one of the two major clusters comprising the Coma Supercluster. It is located in and takes its name from the constellation Coma Berenices. The cluster's mean distance from Earth is 99 Parsec, Mpc (321 million light years). Its ten brightest spiral galaxies have apparent magnitudes of 12–14 that are observable with amateur telescopes larger than 20 cm. The central region is dominated by two supergiant elliptical galaxy, elliptical galaxies: NGC 4874 and NGC 4889. The cluster is within a few degrees of the north galactic pole on the sky. Most of the galaxies that inhabit the central portion of the Coma Cluster are ellipticals. Both dwarf and giant ellipticals are found in abundance in the Coma Cluster. Cluster members As is usual for clusters of this richness, the galaxies are overwhelmingly ellipt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
