Messier Objects

The Messier objects are a set of astronomical objects catalogued by French astronomer Charles Messier in his catalogue of Nebulae and Star Clusters first published in 1774. The original motivation of the catalogue was that Messier was a comet hunter, and was frustrated by objects which resembled but were not comets. He therefore compiled a list of these objects.

The first edition covered 45 objects numbered M1 to M45. The total list consists of 110 objects, ranging from M1 to M110. Messier 102 cannot be positively identified; likely candidates are the galaxies Messier 101 and NGC 5866.

The final catalogue was published in 1781 and printed in the Connaissance des Temps in 1784. Many of these objects are still known by their Messier number.

Because Messier lived and did his astronomical work in France in the Northern Hemisphere, the list he compiled contains only objects from the north celestial pole to a celestial latitude of about –35°. Many impressive Southern objects, such as the Large and Small Magellanic Clouds are excluded from the list.