Facts About The Messier Catalog
The catalog was published in three installments beginning in 1774, it covered objects M1 through M45. A supplement was published in 1780 covering objects up to M68. The final supplement was published in 1781 and covered objects up to M103. He was assisted in his endeavor by his friend and assistant, Pierre Mechain.
Between 1921 and 1966, seven additional objects have been added to the catalog, with the final total being 110 objects. Many of these objects had been observed by Messier, but were not added to his catalog.
Another feature, and an important one, is that the objects in the catalog were discovered using the primitive telescopes of the day. Therefore, they are objects that can easily be seen and studied by amateur astronomers today.
The Messier Colophon, published with his catalog.
The Current Catalog with 110 objects:
Messier was one of the first astronomers that studied deep sky objects.
Image Messier Catalog: http://www.maa.clell.de/Messier/objects.html
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