The planetary nebula Abell 12 earned the nickname "Hidden Pearl" due to its challenging observability. This celestial object, with a magnitude of 14, is situated in close proximity to the 4th magnitude star μ Orionis.

Located near the star μ Orionis, Abell 12 poses a challenge for observers due to its faintness, earning it the poetic moniker "Hidden Pearl." Its 14th magnitude makes it a subtle and elusive target in the night sky.