Messier 110 (also known as M110 and NGC 205) is a dwarf elliptical galaxy that is a satellite of the Andromeda Galaxy. M110 contains some dust and hints of recent star formation, which is unusual for dwarf elliptical galaxies in general.
M110 was serendipitously discovered on August 10, 1773 by Charles Messier, who was making observations of the Andromeda Galaxy at the time. The galaxy was independently discovered by Caroline Herschel on August 27, 1783; her brother William Herschel described her discovery in 1785. Although the galaxy was not originally included in Messier's first catalogue, it was later added by Kenneth Glyn Jones in 1966. Messier 110 remains the last object added to the Messier catalog.