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NGC 2281
NGC 2281 is an open cluster of stars in the northern constellation of Auriga. It was discovered by English astronomer William Herschel on March 4, 1788 and described as a, "cluster of coarsely scattered pretty rightstars, pretty rich". The Trumpler class for NGC 2281 is I3p, indicating a poor (p) but compact (I) grouping with a wide range of brightness (3). It is located at a distance of approximately from the Sun and is 630–661 million years old. References External links * Image NGC 2281NGC 2281* {{DEFAULTSORT:NGC 2281 NGC 2281 NGC 2281 is an open cluster of stars in the northern constellation of Auriga. It was discovered by English astronomer William Herschel on March 4, 1788 and described as a, "cluster of coarsely scattered pretty rightstars, pretty rich". The T ... 2281 Open clusters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 2281
NGC 2281 is an open cluster of stars in the northern constellation of Auriga. It was discovered by English astronomer William Herschel on March 4, 1788 and described as a, "cluster of coarsely scattered pretty rightstars, pretty rich". The Trumpler class for NGC 2281 is I3p, indicating a poor (p) but compact (I) grouping with a wide range of brightness (3). It is located at a distance of approximately from the Sun and is 630–661 million years old. References External links * Image NGC 2281NGC 2281* {{DEFAULTSORT:NGC 2281 NGC 2281 NGC 2281 is an open cluster of stars in the northern constellation of Auriga. It was discovered by English astronomer William Herschel on March 4, 1788 and described as a, "cluster of coarsely scattered pretty rightstars, pretty rich". The T ... 2281 Open clusters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auriga (constellation)
Auriga is a constellation in the northern celestial hemisphere. It is one of the 88 modern constellations; it was among the 48 constellations listed by the 2nd-century astronomer Ptolemy. Its name is Latin for '(the) charioteer', associating it with various mythological beings, including Erichthonius and Myrtilus. Auriga is most prominent during winter evenings in the northern Hemisphere, as are five other constellations that have stars in the Winter Hexagon asterism. Because of its northern declination, Auriga is only visible in its entirety as far south as -34°; for observers farther south it lies partially or fully below the horizon. A large constellation, with an area of 657 square degrees, it is half the size of the largest, Hydra. Its brightest star, Capella, is an unusual multiple star system among the brightest stars in the night sky. Beta Aurigae is an interesting variable star in the constellation; Epsilon Aurigae, a nearby eclipsing binary with an unusually long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collinder Catalogue
In astronomy, the Collinder catalogue is a catalogue of 471 open clusters by Swedish astronomer Per Collinder. It was published in 1931 as an appendix to Collinder's paper ''On structural properties of open galactic clusters and their spatial distribution''. Catalogue objects are denoted by ''Collinder'', e.g. "Collinder 399". Dated prefixes include as ''Col + catalogue number'', or ''Cr + catalogue number'', e.g. "Cr 399". Vital statistics * The catalogue contains 471 objects: 452 open clusters, 11 globular clusters, 6 Asterism (astronomy), asterisms, 1 Stellar kinematics#Moving groups, stellar moving group, and 1 Stellar kinematics#Stellar associations, stellar association. * Objects are spread out across the entire celestial sphere. * NGC 188, Cr 8 is the northernmost Collinder object, located at a declination of +85º in the constellation Camelopardalis. * Cr 411 is the southernmost Collinder object, located at a declination of -79º in the constellation Octans. Collinder obj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philibert Jacques Melotte
Philibert Jacques Melotte (29 January 1880 – 30 March 1961) was a British astronomer whose parents emigrated from Belgium. In 1908 he discovered a moon of Jupiter, today known as Pasiphaë. It was simply designated "Jupiter VIII" and was not given its present name until 1975. The outer main-belt asteroid 676 Melitta, the only asteroid he discovered, is named after the Attic form of the Greek ''Melissa'', the bee, but its resemblance to the discoverer's name is not fortuitous. The conspicuous star cluster in the Coma Berenices constellation is commonly designated Mel 111 since it appeared in Melotte's 1915 catalogue of star clusters,Melotte, P. J"A Catalogue of Star Clusters shown on Franklin-Adams Chart Plates" ''MmRAS'', 1915 but not in Charles Messier's famous catalogue of deep sky objects or in the New General Catalogue since it was not proved to be a true cluster until 1938 by the astronomer R J Trumpler. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star Cluster
Star clusters are large groups of stars. Two main types of star clusters can be distinguished: globular clusters are tight groups of ten thousand to millions of old stars which are gravitationally bound, while open clusters are more loosely clustered groups of stars, generally containing fewer than a few hundred members, and are often very young. Open clusters become disrupted over time by the gravitational influence of giant molecular clouds as they move through the galaxy, but cluster members will continue to move in broadly the same direction through space even though they are no longer gravitationally bound; they are then known as a stellar association, sometimes also referred to as a ''moving group''. Star clusters visible to the naked eye include the Pleiades, Hyades, and 47 Tucanae. Open cluster Open clusters are very different from globular clusters. Unlike the spherically distributed globulars, they are confined to the galactic plane, and are almost always found wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OCL (astronomical Catalog) , football tournament
{{disambiguation ...
The initialism OCL can have several meanings, depending on context: *OCl−, the hypochlorite ion, in chemistry * Open Content License *Object Constraint Language * IBM Open Class Library * Operational Control Language of IBM mid-range computers *Overseas Containers Limited, former shipping company *OFC Champions League The OFC Champions League, also known as the O-League, is the premier men's club soccer competition in Oceania. It is organised by the OFC, Oceania's football governing body. Beginning as the Oceania Club Championship (1987–2006), it has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Cluster
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravity, gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a migration to the main body of the galaxy and a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral galaxy, spiral and irregular galaxy, irregular galaxies, in which active star formation is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the earliest constellations likely go back to prehistory. People used them to relate stories of their beliefs, experiences, creation myth, creation, or mythology. Different cultures and countries adopted their own constellations, some of which lasted into the early 20th century before today's constellations were internationally recognized. The recognition of constellations has changed significantly over time. Many changed in size or shape. Some became popular, only to drop into obscurity. Some were limited to a single culture or nation. The 48 traditional Western constellations are Greek. They are given in Aratus' work ''Phenomena'' and Ptolemy's ''Almagest'', though their origin probably predates these works by several centuries. Constellation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Herschel
Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel (1750–1848). Born in the Electorate of Hanover, William Herschel followed his father into the military band of Hanover, before emigrating to Great Britain in 1757 at the age of nineteen. Herschel constructed his first large telescope in 1774, after which he spent nine years carrying out sky surveys to investigate double stars. Herschel published catalogues of nebulae in 1802 (2,500 objects) and in 1820 (5,000 objects). The resolving power of the Herschel telescopes revealed that many objects called nebulae in the Messier catalogue were actually clusters of stars. On 13 March 1781 while making observations he made note of a new object in the constellation of Gemini. This would, after several weeks of verification and consultation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trumpler Class
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a migration to the main body of the galaxy and a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral and irregular galaxies, in which active star formation is occurring. Young open clusters may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting original research in relevant fields. Despite the name, the journal is no longer monthly, nor does it carry the notices of the Royal Astronomical Society. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second volume, after the Astronomical Society of London became the Royal Astronomical Society (RAS). Until 1960 it carried the monthly notices of the RAS, at which time these were transferred to the newly established ''Quarterly Journal of the Royal Astronomical Society'' (1960–1996) and then to its successor journal ''Astronomy & Geophysics'' (since 1997). Until 1965, MNRAS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
