New General Catalogue

The New General Catalogue (NGC) is the best-known catalogue of deep sky objects in amateur astronomy. It contains nearly 8,000 objects, known as the NGC objects. The NGC is one of the largest comprehensive catalogues, as it includes all types of deep sky objects (not specialised to just galaxies for instance).
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A catalogue of non-stellar celestial objects that was compiled by JLE Dreyer of Armagh Observatory and published in 1888. The original listed 7,840 objects and was followed by a supplement which now includes 5,386 not on the original. Objects on the original list are identified by the letter NGC followed by the catalogue number. Those objects on the supplement are denoted by the letters IC followed by the catalogue number.