Charles Messier
Charles Messier (1730-06-26 - 1817-04-12) was a French astronomer who in 1774 published a catalogue of 45 deep sky objects such as nebulae and star clusters. The purpose of the catalogue was to help comet hunters (like himself) and other naked-eye observers to distinguish between permanent and transient objects in the sky.
By 1781 the catalogue had grown to 110 'Messier Objects'. The objects' designations, from M1 to M110, are mostly still in use today.
The Messier crater on the Moon and the asteroid 7359 Messier were named in his honour.