| PAM | Payload Assist Module | - | Atmospheric Research Center |
| PAM-D | Payload Assist Module | - | Atmospheric Research Center |
| PARE | Physiological And Anatomical Rodent Experiment | - | Atmospheric Research Center |
| PASS | Primary Avionics Software System | - | Atmospheric Research Center |
| PC | ParseC (usu. Pc) | - | Atmospheric Research Center |
| PCG | Protein Crystal Growth Experiment | - | Atmospheric Research Center |
| PCGG | PCG Glovebox | - | Atmospheric Research Center |
| PCT | Photometric Calibration Test | - | Atmospheric Research Center |
| PDE | Particle Dispersion Experiment | - | Atmospheric Research Center |
| PDRS | Payload Deployment And Retrieval System | - | Atmospheric Research Center |
| PDS | Planetary Data System | - | Atmospheric Research Center |
| PEM | Payload Electronics Module | - | Atmospheric Research Center |
| PEM | Particle Environment Monitor | - | Atmospheric Research Center |
| PHA | Physics And Astronomy | - | Atmospheric Research Center |
| PI | Principal Investigator | - | Atmospheric Research Center |
| PLB | Payload Bay | - | Atmospheric Research Center |
| PLBD | Payload Bay Doors | - | Atmospheric Research Center |
| PLSS | Portable Life Support System | - | Atmospheric Research Center |
| PM | Pressurized Module | - | Atmospheric Research Center |
| PMC | Permanently Manned Capability | - | Atmospheric Research Center |
| PMIRR | Pressure Modulated InfraRed Radiometer | - | Atmospheric Research Center |
| PMS | Pre-Main Sequence | - | Atmospheric Research Center |
| PMT | PhotoMultiplier Tube | - | Atmospheric Research Center |
| PN | Planetary Nebula | - | Atmospheric Research Center |
| POCC | Payload/Platform Operations Control Center | - | Atmospheric Research Center |
| POEM | Polar Orbiting Earth Mission | - | Atmospheric Research Center |
| POP | PO Polyot | - | Atmospheric Research Center |
| PPF | Columbus Polar Platform | - | Atmospheric Research Center |
| PPM | Positions And Proper Motions (catalog) | - | Atmospheric Research Center |
| PRTLS | Powered RTLS | - | Atmospheric Research Center |
| PSF | Point Spread Function | - | Atmospheric Research Center |
| PSR | PulSaR | - | Atmospheric Research Center |
| PTC | Passive Thermal Control | - | Atmospheric Research Center |
| PV | Photovoltaic | - | Atmospheric Research Center |
| PVO | Pioneer Venus Orbiter / Protivo-Vosdushniya Oborona | - | Atmospheric Research Center |
