ocr: (1730-1817) CHARLES MESSIER was a French astronomer who spent 24 years compiling a catalog of night-sky objects called nebulas. (A nebula is a giant cloud of gas and dust.) His aim was to list all of the objects that might be confused with comets so that future night-sky observers could distinguish between them. Each object in his catalog bears an M, for "Messier," and a number. (For example, M 8 is a nebula in the constellation of Sagittarius.) His catalog is still used today, although some of the objects that Messier listed as nebulas are now known to be galaxies or star clusters. 1730 Born ...
