| Abbreviation | Definition |
|---|---|
| PIFOV | Planet In Field Of View |
| PLE | Partial Lunar Eclipse |
| PMA | Physics Mathematics and Astronomy |
| PN | Planetary Nebulae |
| PNS | Pulsed Neutron Source |
| PNX | Pulsar Network Exchange |
| PO | Primary Object |
| POA | Physics Optics Astronomy |
| POA | Physics, Optics, Astronomy |
| POGTTNDF | Planning On Going To The Next Dimension Fourth |
| POSS | Palomar Observatory Sky Survey |
| POTS | Physics Of The Sun |
| PPNe | Proto-Planetary Bebulae |
| PRϿ | Promise Ring from the Sun |
| PR? | Promise Ring from the Sun |
| PRAO | Pushchino Radio Astronomy Observatory |
| PROBA | Project for On-Board Autonomy |
| PRÿ | Promise Ring from the Sun |
| PS-1 | Panoramic Survey Telescope and Rapid Response System 1 |
| PSA | Planetary Science Archive |