The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his Catalogue des Nébuleuses et des Amas d'Étoiles.
Because Messier was interested only in finding comets, he created a list of those non-comet objects that frustrated his hunt for them. This list, which Messier created in collaboration with his assistant Pierre Méchain, is now known as the Messier catalogue. The Messier catalogue is one of the most famous lists of astronomical objects, and many objects on the list are still referenced by their Messier numbers.
The catalogue includes most of the astronomical deep-sky objects that can be easily observed from Earth's Northern Hemisphere; many Messier objects are popular targets for amateur astronomers.
All Messier objects
Charles Messier
Image: Crab Nebula
Image: Messier 2 HST Potw 1913a
Charles Messier was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the Messier objects, referred to with the letter M and their number between 1 and 110. Messier's purpose for the catalogue was to help astronomical observers distinguish between permanent and transient visually diffuse objects in the sky.
Charles Messier, c. 1770
Messier's grave in Père Lachaise
The Orion Nebula as drawn by Messier, and which he gave the designation M 42 in his catalogue
Commemorative plaque in Messier's hometown of Badonviller