M102
Messier 102 (also known as M102) taken on May 4, 2014 is a galaxy listed in the Messier Catalogue that has not been identified unambiguously. Its original discoverer Pierre Méchain later said that it was a duplicate observation of Messier 101, but there are historical and observational reasons to believe that it could be NGC 5866, although other galaxies have been suggested as possible identities.