The New General Catalogue of Nebulae and Clusters of Stars (abbreviated as NGC) is a catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. It expands upon the cataloguing work of William and Caroline Herschel, and John Herschel's General Catalogue of Nebulae and Clusters of Stars. The NGC contains 7,840 objects, known as the NGC objects. It is one of the largest comprehensive catalogues, as it includes all types of deep space objects, including galaxies, star clusters, emission nebulae and absorption nebulae. Dreyer also published two supplements to the NGC in 1895 and 1908, known as the Index Catalogues, describing a further 5,386 astronomical objects.
Objects in the sky of the southern hemisphere are catalogued somewhat less thoroughly, but many were observed by John Herschel or James Dunlop. The NGC had many errors, but an attempt to eliminate them was initiated by the NGC/IC Project in 1993, after partial attempts with the Revised New General Catalogue (RNGC) by Jack W. Sulentic and William G. Tifft in 1973, and NGC2000.0 by Roger W. Sinnott in 1988. The Revised New General Catalogue and Index Catalogue was compiled in 2009 by Wolfgang Steinicke.
|New General Catalogue|
Spiral Galaxy NGC 3982 displays numerous spiral arms filled with bright stars, blue star clusters, and dark dust lanes. It spans about 30,000 light years, lies about 68 million light years from Earth and can be seen with a small telescope in the constellation of Ursa Major.
The original New General Catalogue was compiled during the 1880s by John Louis Emil Dreyer using observations from William Herschel and his son John, among others. Dreyer had already published a supplement to Herschel's General Catalogue of Nebulae and Clusters (GC), containing about 1,000 new objects. In 1886, he suggested building a second supplement to the General Catalogue, but the Royal Astronomical Society asked Dreyer to compile a new version instead. This led to the publication of the New General Catalogue in the Memoirs of the Royal Astronomical Society in 1888.
Assembling the NGC was a challenge, as Dreyer had to deal with many contradicting and unclear reports, made with a variety of telescopes with apertures ranging from 2 to 72 inches. While he did check some himself, the sheer number of objects meant Dreyer had to accept them as published by others for the purpose of his compilation. The catalogue contained several errors, mostly relating to position and descriptions, but Dreyer referenced the catalogue, which allowed later astronomers to review the original references and publish corrections to the original NGC.
The first major update to the NGC is the Index Catalogue of Nebulae and Clusters of Stars (abbreviated as IC), published in two parts by Dreyer in 1895 (IC I, containing 1,520 objects) and 1908 (IC II, containing 3,866 objects). It serves as a supplement to the NGC, and contains an additional 5,386 objects, collectively known as the IC objects. It summarizes the discoveries of galaxies, clusters and nebulae between 1888 and 1907, most of them made possible by photography. A list of corrections to the IC was published in 1912.
The Revised New Catalogue of Nonstellar Astronomical Objects (abbreviated as RNGC) was compiled by Jack W. Sulentic and William G. Tifft in the early 1970s, and was published in 1973, as an update to the NGC. The work did not incorporate several previously-published corrections to the NGC data (including corrections published by Dreyer himself), and introduced some new errors.
Nearly 800 objects are listed as "non-existent" in the RNGC. The designation is applied to objects which are duplicate catalogue entries, those which were not detected in subsequent observations, and a number of objects catalogued as star clusters which in subsequent studies were regarded as coincidental groupings. A 1993 monograph considered the 229 star clusters called non-existent in the RNGC. They had been "misidentified or have not been located since their discovery in the 18th and 19th centuries". It found that one of the 229—NGC 1498—was not actually in the sky. Five others were duplicates of other entries, 99 existed "in some form", and the other 124 required additional research to resolve.
As another example, reflection nebula NGC 2163 in Orion was classified "non-existent" due to a transcription error by Dreyer. Dreyer corrected his own mistake in the Index Catalogues, but the RNGC preserved the original error, and additionally reversed the sign of the declination, resulting in NGC 2163 being classified as non-existent.
NGC 2000.0 (also known as the Complete New General Catalog and Index Catalog of Nebulae and Star Clusters) is a 1988 compilation of the NGC and IC made by Roger W. Sinnott, using the J2000.0 coordinates. It incorporates several corrections and errata made by astronomers over the years.
The NGC/IC Project is a collaboration formed in 1993. It aims to identify all NGC and IC objects, and collect images and basic astronomical data on them.
The Revised New General Catalogue and Index Catalogue (abbreviated as RNGC/IC) is a compilation made by Wolfgang Steinicke in 2009. It is considered one of the most comprehensive and authoritative treatments of the NGC and IC catalogues.
The Catalogue of Nebulae and Clusters of Stars (CN) is an astronomical catalogue of nebulae first published in 1786 by William Herschel, with the assistance of his sister Caroline Herschel. It was later expanded into the General Catalogue of Nebulae and Clusters of Stars (GC) by his son, John Herschel. The CN and GC are the precursors to John Louis Emil Dreyer's New General Catalogue (NGC) used by current astronomers.List of NGC objects
The following is a list of NGC objects, that is objects listed in the New General Catalogue (NGC). It is one of the largest comprehensive astronomical catalogues for deep space objects such as star clusters, nebulae, and galaxies.
List of NGC objects (1–1000)
List of NGC objects (1001–2000)
List of NGC objects (2001–3000)
List of NGC objects (3001–4000)
List of NGC objects (4001–5000)
List of NGC objects (5001–6000)
List of NGC objects (6001–7000)
List of NGC objects (7001–7840)NGC 1000
NGC 1000 is an elliptical galaxy located in the constellation of Andromeda. It was discovered on December 9, 1871 by Édouard Jean-Marie Stephan. It is the 1,000th object classified by the New General Catalogue.NGC 121
NGC 121 is a globular cluster in the Small Magellanic Cloud, in the constellation of Tucana. It was first discovered by John Herschel on September 20, 1835. The compiler of the New General Catalogue, John Louis Emil Dreyer, described this object as "pretty bright, pretty small, little extended, very gradually brighter middle".NGC 124
NGC 124 is a spiral galaxy in the constellation Cetus. It was discovered by Truman Henry Safford on September 23, 1867. The galaxy was described as "very faint, large, diffuse, 2 faint stars to northwest" by John Louis Emil Dreyer, the compiler of the New General Catalogue.NGC 157
NGC 157 is a spiral galaxy in the constellation of Cetus. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 157 was "pretty bright, large, extended, between 2 considerably bright stars". It was discovered on December 13, 1783 by William Herschel.NGC 17
NGC 17, also known as NGC 34, is a spiral galaxy in the constellation Cetus. It is the result of a merger between two disk galaxies, resulting in a recent starburst in the central regions and continuing starforming activity. The galaxy is still gas-rich, and has a single galactic nucleus. It lies 250 million light years away. It was discovered in 1886 by Frank Muller and then observed again later that year by Lewis Swift.
Due to the major merger event NGC 17 has no defined spiral arms like the Milky Way galaxy. Unlike the Milky Way, the center bar nucleus is also distorted. The merger destroyed any galactic habitable zone that may have been there before the merger. For the Milky Way, the galactic habitable zone is commonly believed to be an annulus with an outer radius of about 10 kiloparsecs and an inner radius close to the Galactic Center, both of which lack hard boundaries.NGC 178
NGC 178 is a spiral galaxy in the constellation of Cetus. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 178 was "faint, small, much extended 0°, brighter middle". It was discovered on November 3, 1885 by Ormond Stone.NGC 21
NGC 21 (also known as NGC 29) is a spiral galaxy in the Andromeda constellation. It was discovered by William Herschel in 1790. Lewis Swift observed it again in 1885, leading to its double listing in the New General CatalogueNGC 210
NGC 210 is a barred spiral galaxy located roughly 67 million light-years from the Solar System in the constellation Cetus. It was discovered on October 3, 1785 by William Herschel and later added to the New General Catalogue.NGC 275
NGC 275 is a spiral galaxy located approximately 63 million light-years from the Solar System in the constellation Cetus. It is one of a pair of galaxies, the other being NGC 274. It was discovered on October 9, 1828 by John Herschel.The galaxy was described as "very faint, small, round, southeastern of 2" by John Dreyer in the New General Catalogue, with the other of the two galaxies being NGC 274.NGC 276
NGC 276 is a barred spiral galaxy located approximately 626 million light-years from the Solar System in the constellation Cetus. It was discovered in 1886 by Frank Muller and was later also observed by DeLisle Stewart.John Dreyer, creator of the New General Catalogue describes the object as "extremely faint, pretty small, extended 265°, 11 magnitude star 3 arcmin to north". The galaxy's right ascension was later corrected in the Index Catalogue using the observation data by Stewart.NGC 289
NGC 289 is a spiral galaxy in the constellation of Sculptor. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 289 was "pretty bright, large, extended, between 2 considerably bright stars". It was discovered on September 27, 1834 by John Herschel.NGC 352
NGC 352 is a barred spiral galaxy in the constellation Cetus. It was discovered on September 20, 1784 by William Herschel. It was described as "pretty faint, small, irregularly extended" by John Louis Emil Dreyer, the compiler of the New General Catalogue; he also noted an "8th magnitude star 97 seconds of time to east" relative to the galaxy.NGC 405
HD 6869 is a 7th magnitude star located in the constellation of Phoenix. It was discovered on September 6, 1834 by John Herschel and later led to the entry NGC 405 in the New General Catalogue.NGC 459
NGC 459, also known as UGC 832, MCG 3-4-17, ZWG 459.24, and PGC 4665, is a spiral galaxy in the constellation Pisces. It was discovered on October 15, 1784, by William Herschel. It was described as being extremely faint by John Dreyer in the New General Catalogue.NGC 48
The New General Catalogue object NGC 48 is a barred spiral galaxy located approximately 79.3 million light-years from the Solar System in the constellation Andromeda.NGC 490
NGC 490, also occasionally referred to as PGC 4973 or GC 277, is a lenticular galaxy in the constellation Pisces. It is located approximately 85 million light-years from Earth and was discovered on December 6, 1850, by Irish engineer Bindon Blood Stoney. Although John Dreyer, creator of the New General Catalogue, credits the discovery to astronomer William Parsons, he notes that many of his claimed discoveries were made by one of his assistants. In the case of NGC 490, the discovery was made by Bindon Stoney, who discovered it along with NGC 486, NGC 492 and NGC 500 during his observation of NGC 488. The object was initially described in the New General Catalogue as "very faint, very small, round, 8 arcmin northeast of h 103 (=NGC 488)".NGC 493
NGC 493, also occasionally referred to as PGC 4979 or GC 281, is a barred spiral galaxy in the constellation Cetus. It is located approximately 90 million light-years from Earth and was discovered on December 20, 1786 by astronomer William Herschel. It was later also observed by his son, John Herschel. John Dreyer, creator of the New General Catalogue, described the galaxy as "very faint, large, much extended 60°" with "a little brighter middle".