Changes

==History==

==History==

The NGC catalogue was first published in 1888 and contains some 7,840 objects.<ref name=NGCIC_Mission>[http://ngcicproject.org/mission.htm NGC/IC Mission] from ngcicproject.org</ref><ref name=freestarcharts/> This was an attempt by Dreyer to collate all the known objects, such as [[nebulae]] and [[globular cluster]]s, into a single catalogue. Previously, there had been many catalogues, including some famous ones such as the [[Messier catalogue]], but these were becoming outdated as more powerful telescopes allowed for the observation of fainter deep sky objects. As an example, Messier's catalogue from 1771 contains around 100 objects whilst [[John Herschel]]'s General Catalogue created in 1864 contains some 5,079 objects.<ref>[http://www.messier.seds.org/xtra/history/m-cat.html Charles Messier's Catalog of Nebulae and Star Clusters] from messier.seds.org</ref><ref name=freestarcharts/> Later catalogues did not also include all previously known objects. Herschel specifically tried to avoid including entries in the Messier Catalogue in his.<ref name=seds>[http://www.messier.seds.org/xtra/similar/herschel.html William Herschel's catalog of Deep Sky objects] from messier.seds.org</ref> Dreyer used any source of data he could find. As this meant data was collected by numerous people, using numerous different instruments, various observation conditions, this lead to various errors in the NGC catalogue. Some entries are repeated and others point to blank patches of sky.

The NGC catalogue was first published in 1888 and contains some 7,840 objects.<ref name=freestarcharts/><ref name=NGCIC_Mission>[http://ngcicproject.org/mission.htm NGC/IC Mission] from ngcicproject.org</ref> This was an attempt by Dreyer to collate all the known objects, such as [[nebulae]] and [[globular cluster]]s, into a single catalogue. Previously, there had been many catalogues, including some famous ones such as the [[Messier catalogue]], but these were becoming outdated as more powerful telescopes allowed for the observation of fainter deep sky objects. As an example, Messier's catalogue from 1771 contains around 100 objects whilst [[John Herschel]]'s General Catalogue created in 1864 contains some 5,079 objects.<ref name=freestarcharts/><ref>[http://www.messier.seds.org/xtra/history/m-cat.html Charles Messier's Catalog of Nebulae and Star Clusters] from messier.seds.org</ref> Later catalogues did not also include all previously known objects. Herschel specifically tried to avoid including entries in the Messier Catalogue in his.<ref name=seds>[http://www.messier.seds.org/xtra/similar/herschel.html William Herschel's catalog of Deep Sky objects] from messier.seds.org</ref> Dreyer used any source of data he could find. As this meant data was collected by numerous people, using numerous different instruments, various observation conditions, this led to various errors in the NGC catalogue. Some entries are repeated and others point to blank patches of sky.

After publishing the New General catalogue, Dreyer published the Index catalogues, the first in 1895 and the second in 1908. Denoted as IC I and IC II, these added a further 1,520 and 3,866 objects.<ref name=freestarcharts/>

After publishing the New General catalogue, Dreyer published the Index catalogues, the first in 1895 and the second in 1908. Denoted as IC I and IC II, these added a further 1,520 and 3,866 objects.<ref name=freestarcharts/>