French astronomer remembered for his catalog listing many of the most important nebulae and clusters. Messier was widely known by his contemporaries for discovering comets—15 by modern standards. Having been deceived numerous times by comet-like nebulosities, he compiled and published his Messier list of such objects. These are today known as Messier objects and designated M1, M2, etc, and include the Crab Nebula (M1), the Andromeda galaxy (M31), and the Pleiades (M45).
"Charles Messier." Science and Its Times: Understanding the Social Significance of Scientific Discovery. . Encyclopedia.com. (September 24, 2018). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/charles-messier
"Charles Messier." Science and Its Times: Understanding the Social Significance of Scientific Discovery. . Retrieved September 24, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/charles-messier