What does PNN stand for?
PNN stands for "Planetary Nebula Nucleus"
How to abbreviate "Planetary Nebula Nucleus"?
"Planetary Nebula Nucleus" can be abbreviated as PNN
What is the meaning of PNN abbreviation?
The meaning of PNN abbreviation is "Planetary Nebula Nucleus"
What does PNN mean?
PNN as abbreviation means "Planetary Nebula Nucleus"