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

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 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...

, nebula

Nebula

A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases...

e and star cluster

Star cluster

Star clusters or star clouds are groups of stars. Two types of star clusters can be distinguished: globular clusters are tight groups of hundreds of thousands of very old stars which are gravitationally bound, while open clusters, more loosely clustered groups of stars, generally contain less than...

s that serves as a supplement

Supplement (publishing)

A supplement is a publication that has a role secondary to that of another preceding or concurrent publication.A follow-on publication complements its predecessor, either by bringing it up-to-date , or by otherwise enhancing the predecessor's coverage of a particular topic or subject matter, as in...

 to the New General Catalogue

New General Catalogue

The New General Catalogue of Nebulae and Clusters of Stars is a well-known catalogue of deep sky objects in astronomy. It contains 7,840 objects, known as the NGC objects...

. It was first published in 1895, and has been expanded to list 5,386 objects, known as the IC objects.

The catalogue was compiled by J. L. E. Dreyer in the 1880s, who published it as two appendices

Addendum

An addendum, in general, is an addition required to be made to a document by its reader subsequent to its printing or publication. It comes from the Latin verbal phrase addendum est, being the gerundive form of the verb addo, addere, addidi, additum, "to give to, add to", meaning " must be added"...

 (IC I& IC II) to the New General Catalogue. It summarized the discoveries of galaxies, clusters and nebulae between 1888 and 1907.

See also

• 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
• 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