I quoted the designation from NSOG, including the question mark.
If it's a normal PN, why did it not respond to O3 or Hbeta?
mam
> b) Matthew Marcus was puzzling over NSOG's designation of the Egg
> Nebula as a protoplanetary nebula. Now Matthew, you put a question
> mark right there. Assuming you know the right answer, still for the
> benefit of the reading public, it's no such thing. Definitely a
> planetary.
>