Discovered by Pierre Méchain in 1780
Messier 77 is a very large spiral galaxy located approximately 60 million light years distant. It is classified as a type II Seyfert galaxy and is the largest and closest galaxy of this type. It is estimated to contain a mass equal to a trillion times that of our Sun. The bright part of its disk is about 120,000 light years across and its faint outer limits extend to approximately 170,000 light years in diameter. It contains a powerful and very active central core. Astronomers believe a super-massive black hole lies at the center of its core.