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