The Messier Catalogue is a list of astronomical objects made by French astronomer Charles Messier in 1771. Messier was a comet hunter, and was annoyed by objects which were not comets. He put together a list of these objects, with his assistant Pierre Méchain.
The list is still used by astronomers, mainly because they are very familiar with it.
The objects have 'M' in front. He was limited by the objects he could see from France so the list is incomplete by today's standards but it remains popular due to the length of time it has been around and astronomers' familiarity with these objects.
The first edition covered 45 objects numbered M1 to M45. The total list published by Messier finally contained 103 objects, and the list was made up to 110 by modern astronomers working from Messier's notes..
Other catalogues exist, most notably the New General Catalogue.
Items on the list
Almost all the items are either star clusters or nebulae. There are only three galaxies in the first fifty, starting with Andromeda at M31. Individual stars are not listed. The first ten in the list are:
M1 NGC 1952 Crab nebula, a supernova remnant
M2 NGC 7089 a globular cluster
M3 NGC 5272 a globular cluster
M4 NGC 6121 a globular cluster
M5 NGC 5904 a globular cluster
M6 NGC 6405 Butterfly cluster, an open cluster
M7 NGC 6475 Ptolemy cluster, an open cluster
M8 NGC 6523 Lagoon nebula, a nebula with a cluster
M9 NGC 6333 a globular cluster
💯 M10 NGC 6254 a globular cluster
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