Messier 77

Messier 77, also cataloged as NGC 1068, is a barred spiral galaxy in Cetus with a bright active galactic nucleus powered by accretion onto a supermassive black hole.

Active galactic nucleus: A compact, exceptionally luminous galactic center powered by matter accreting onto a central supermassive black hole. Messier 77’s bright nucleus places it in this broader class.
Barred spiral galaxy: A spiral galaxy whose central stars form an elongated bar from which spiral arms extend. Messier 77’s stellar bar and spiral arms define its large-scale form.
Seyfert 2 galaxy: A Seyfert galaxy whose broad nuclear emission lines are obscured in direct view. Messier 77 is the archetypal example of this active-galaxy subtype.
Charles Messier: An eighteenth-century French astronomer who compiled a catalog of nebulae and star clusters. He recorded this galaxy as the seventy-seventh entry in his catalog.
Seyfert galaxy: A galaxy whose active nucleus produces strong emission lines and is relatively accessible to observation. Messier 77 is the prototype of a Seyfert 2 galaxy.
Cetus: A large constellation in the equatorial sky, named for a sea monster in Greek mythology. Messier 77 lies within this constellation as seen from Earth.
Very Large Array: A radio astronomy observatory in New Mexico consisting of 27 movable antennas. Radio observations resolved structures in Messier 77’s compact nucleus and outflow.
New General Catalogue: A nineteenth-century catalog of nebulae and star clusters compiled by John Louis Emil Dreyer. Its entry NGC 1068 is the galaxy’s other standard catalog designation.
Supermassive black hole: A black hole with a mass of millions to billions of Suns, commonly found at a galaxy’s center. Accretion onto Messier 77’s central black hole powers its nucleus.
NGC 1068: The New General Catalogue designation for the galaxy also known as Messier 77. This alternate catalog name identifies the same object, not a neighboring galaxy.

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