In 1781 the French astronomer Charles Messier published his catalog of star clusters and nebulae. Officially, the principal catalog of these objects is the New General Catalogue of Clusters and Nebulae, drawn up by J. L. E. Dreyer in 1888, but the Messier numbers are much more widely used by amateur astronomers. For example, the Andromeda Nebula is much more widely known as M31 than as NGC 224. Recently, the Caldwell catalog has been compiled to list notable objects that are absent from the Messier catalog.