The Messier Catalogue

Charles Messier was not a Deep-sky observer he was a comet hunter. During his many searches, he found that misty objects kept on getting in his way because they resembled comets. Messier set out to remedy this for other comet hunters as well as himself by listing all of these misy patches in his famous catalogue of 110 deep-sky objects which today is known as the Messier Catalogue. The final version of the catalogue was published in 1781, in the 1784 issue of Connaissance des Temps. The final list of Messier objects had grown to 103. On several occasions between 1921 and 1966, astronomers and historians discovered evidence of another seven objects that were observed either by Messier or by Méchain, shortly after the final version was published. These seven objects, M 104 through M 110, are accepted by astronomers as "official" Messier objects.