Retcon article
(covers information that was retroactively changed)
The Dumbbell Nebula was a nebula located in the Alpha or Beta Quadrant. This nebula was approximately 1,360 light years from Sol.
An image depicting the Dumbbell Nebula was scanned by the Talosians as they reviewed the library computer files on board USS Enterprise in 2254. (TOS: "The Cage")