New General Catalogue
Encyclopedia
The New General Catalogue of Nebulae and Clusters of Stars (NGC) is a well-known catalogue
Astronomical catalog
An astronomical catalog or catalogue is a list or tabulation of astronomical objects, typically grouped together because they share a common type, morphology, origin, means of detection, or method of discovery...

 of deep sky objects in astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

. It contains 7,840 objects, known as the NGC objects. The NGC is one of the largest comprehensive catalogues, as it includes all types of deep space objects and is not confined to, for example, galaxies
Galaxy
A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...

.

History

The catalogue was compiled during the 1880s by J. L. E. Dreyer using observations from William Herschel
William Herschel
Sir Frederick William Herschel, KH, FRS, German: Friedrich Wilhelm Herschel was a German-born British astronomer, technical expert, and composer. Born in Hanover, Wilhelm first followed his father into the Military Band of Hanover, but emigrated to Britain at age 19...

 and his son John
John Herschel
Sir John Frederick William Herschel, 1st Baronet KH, FRS ,was an English mathematician, astronomer, chemist, and experimental photographer/inventor, who in some years also did valuable botanical work...

, among others. Dreyer had already published an update to the Herschel's Catalogue of Nebulae
Catalogue of Nebulae
The Catalogue of Nebulae was first published in 1786 by William Herschel. It was eventually expanded by his son John Herschel into the General Catalogue of Nebulae and Clusters, and further expanded by J. L. E...

, but a new update was refused by the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...

, who asked Dreyer to compile a New General Catalogue. This catalogue was published in 1888. The NGC was later expanded with two Index Catalogue
Index Catalogue
The Index Catalogue —also known as the Index Catalogue of Nebulae, the Index Catalogue of Nebulae and Clusters of Stars, IC I, or IC II— is a catalogue of galaxies, nebulae and star clusters that serves as a supplement to the New General Catalogue...

s (IC I in 1896 & IC II in 1905), adding a further 5,386 objects. Most of these later discoveries had been made possible by photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

.

Objects in the sky of the southern hemisphere
Celestial sphere
In astronomy and navigation, the celestial sphere is an imaginary sphere of arbitrarily large radius, concentric with the Earth and rotating upon the same axis. All objects in the sky can be thought of as projected upon the celestial sphere. Projected upward from Earth's equator and poles are the...

 are catalogued somewhat less thoroughly, but many were observed by John Herschel
John Herschel
Sir John Frederick William Herschel, 1st Baronet KH, FRS ,was an English mathematician, astronomer, chemist, and experimental photographer/inventor, who in some years also did valuable botanical work...

 or James Dunlop
James Dunlop
James Dunlop was an astronomer's assistant who was hired by Sir Thomas Brisbane to work at his private observatory, once located at Paramatta , New South Wales, about twenty-three kilometres west of Sydney, Australia during the 1820s and 1830s...

. The NGC had many errors, but a serious if not complete attempt to eliminate them has been initiated by The NGC/IC Project, after partial attempts with the Revised New General Catalog (RNGC) by Sulentic and Tifft in 1973, and NGC2000.0 by Sinnott in 1988.

The NGC was published in the Memoirs of the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...

as "A New General Catalogue of Nebulae and Clusters of Stars, being the Catalogue of the late Sir John F.W. Herschel, Bart., revised, corrected, and enlarged." (Dreyer J. L. E., 1888, Mem. R. Astron. Soc., 49, 1-237).

See also

  • List of NGC objects
  • Catalogue of Nebulae
    Catalogue of Nebulae
    The Catalogue of Nebulae was first published in 1786 by William Herschel. It was eventually expanded by his son John Herschel into the General Catalogue of Nebulae and Clusters, and further expanded by J. L. E...

  • General Catalogue of Nebulae and Clusters
  • Index Catalogue
    Index Catalogue
    The Index Catalogue —also known as the Index Catalogue of Nebulae, the Index Catalogue of Nebulae and Clusters of Stars, IC I, or IC II— is a catalogue of galaxies, nebulae and star clusters that serves as a supplement to the New General Catalogue...

  • Revised New General Catalogue
    Revised New General Catalogue
    The Revised New General Catalogue and companion Revised Index Catalogue is a revision to the original New General Catalogue and Index Catalogues made by J. L. E. Dreyer. Some of the brightnesses of objects measured by Dreyer were not accurate or the description of the object was not accurate....

  • Revised Index Catalogue

:Category:NGC objects
:Category:IC objects

External links

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