NGC 6992

NGC 6992, also known as Caldwell 33, NGC 6995, and the Eastern Veil Nebula, is a filamentary supernova remnant in the constellation Cygnus, discovered in 1784. It's the eastern arc of the larger Veil Nebula (Cygnus Loop), an expanding shell of ionized gas from a star that exploded roughly 8,000 years ago, spanning about 50 arcminutes.  Apparent magnitude is 8.0. Distance from Earth is 2,000 light-years.