Comments:
The famous ring nebula M57 is often regarded as the prototype of a
planetary nebula, and a showpiece in the northern hemisphere summer sky.

Recent research has confirmed that it is, most probably, actually a ring (torus) of bright light-emitting material surrounding its central star,
and not a spherical (or ellipsoidal) shell, thus coinciding with an early
assumption by John Herschel. Viewed from this equatorial plane, it would
thus more resemble the Dumbbell Nebula M27 or the Little Dumbbell Nebula
M76 than its appearance we know from here: We happen to view it from near one pole.