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NGC 5643
NGC 5643 is an intermediate spiral galaxy in the constellation Lupus (constellation), Lupus. Based on the tip of the red-giant branch distance indicator, it is located at a distance of about 40 million light-years (12.5 megaparsecs). NGC 5643 has an active galactic nucleus and is a type II Seyfert galaxy. Observation history The galaxy was first discovered by James Dunlop on May 10, 1826, with his 9-inch reflector telescope, who described it as exceedingly faint. The galaxy was also spotted by John Herschel and added to the ''General Catalogue of Nebulae and Clusters'' as number 3572. The galaxy is located only 15 degrees from the galactic plane. Structure NGC 5643 is a grand design spiral galaxy, with two well-defined, symmetric arms. In the circumnuclear region are other dust spirals, but the two main dust arms are wider. The galaxy is seen nearly face on, at an inclination of ~ 27°. Active galactic nucleus The galaxy has a low-luminosity active galactic nucleus of Sey ... [...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] |
