NGC stands for New General Catalogue, which is a comprehensive catalogue of deep sky objects that was compiled in the late 19th century. It was originally created by the astronomer John Louis Emil Dreyer, who was the director of the Armagh Observatory in Northern Ireland. The NGC was published in 1888 and contained a list of 7,840 celestial objects, including galaxies, star clusters, nebulae, and other astronomical phenomena.
The NGC catalogue serves as a valuable resource for astronomers, astrophysicists, and amateurs interested in observing and studying celestial objects. Each object listed in the NGC is assigned a unique identifier, such as NGC 1234, which allows for precise identification and referencing. The objects are arranged in a numerical order, but there is no specific physical or spatial organization within the catalogue.
The NGC has since been expanded and updated with additional entries in subsequent editions, including the Index Catalogue (IC) and the Revised New General Catalogue (RNGC). These revisions incorporated new discoveries and observations made by astronomers over the years.
Overall, the NGC provides a standardized and widely accepted reference for astronomers when studying deep sky objects. It helps facilitate research, identification, and communication within the astronomical community, contributing to our collective knowledge of the universe.
