The Messier catalog (M) is a classic astronomical list of 110 deep-sky objects—including galaxies, nebulae, and star clusters.Compiled by 18th-century French astronomer Charles Messier, it famously originated as a “do-not-observe” list to help comet hunters avoid mistaking fixed, fuzzy space objects for actual comets.
The New General Catalogue (NGC) is a legendary, massive astronomical database of deep-sky objects like galaxies, star clusters, and nebulae. Compiled in 1888 by astronomer John L. E. Dreyer, it contains 7,840 celestial objects and remains a fundamental naming system for amateur and professional astronomers.
The Index Catalogue (IC) is a major astronomical database of 5,386 deep-sky objects. Published in two parts in 1895 and 1908 by J. E. L. Dreyer, it serves as the primary supplement to the widely used New General Catalogue (NGC), covering new galaxies, nebulae, and star clusters.
The Sharpless Catalogue is a list of glowing emission nebulae, mostly regions of hydrogen gas where new stars are forming. It was compiled by astronomer Stewart Sharpless in the 1950s and includes many objects labeled with Sh2 numbers, such as Sh2-101 or Sh2-132. Many Sharpless objects are faint, wide-field targets that are popular with astrophotographers using narrowband or dual-band filters.
The Minor Planet Catalog is the official database of asteroids, dwarf planets, and comets in our solar system, maintained by the IAU Minor Planet Center (MPC). It tracks over 1.4 million numbered objects and details their orbits, physical characteristics, and discovery circumstance