| Acronym | Meaning |
![](file.png) | PTC | Passive Thermal Control |
![](file.png) | PV | Photovoltaic |
![](file.png) | PVO | Pioneer Venus Orbiter / Protivo-Vosdushniya Oborona |
![](file.png) | QSO | Quasi-Stellar Object |
![](file.png) | RA | Right Ascension |
![](file.png) | RAE | Royal Aerospace Establishment |
![](file.png) | RAL | Rutherford-Appleton Laboratory |
![](file.png) | RAS | Royal Astronomical Society |
![](file.png) | RASC | Royal Astronomical Society Of Canada |
![](file.png) | RCC | Reinforced Carbon-Carbon |
![](file.png) | RCI | Rodent Cage Interface |
![](file.png) | RCS | Reaction Control System / Revision Control System |
![](file.png) | RCT | Radiometric Calibration Target |
![](file.png) | REM | Rat Enclosure Module |
![](file.png) | RESTEC | Remote Sensing Technology Center |
![](file.png) | RF | Radio Frequency |
![](file.png) | RFI | Radio Frequency Interference |
![](file.png) | RFM | Reconfigurable Furnace Module |
![](file.png) | RFNA | Red Fuming Nitric Acid |
![](file.png) | RG | Red Giant |
![](file.png) | RGB | Red Giant Branch |
![](file.png) | RHC | Rotational Hand Controller |
![](file.png) | RIACS | Research Institute For Advanced Computer Science |
![](file.png) | RKA | Rossiskoye Kosmicheskoye Agentsvo |
![](file.png) | RMCD | Radaiation Monitoring Container Device |
![](file.png) | RME | Radiation Monitoring Experiment |
![](file.png) | RMS | Remote Manipulator System |
![](file.png) | RNGC | Revised New General Catalog |
![](file.png) | ROSAT | ROentgen Satellite |
![](file.png) | ROUS | Rodents Of Unusual Size |
![](file.png) | RPM | Retro Propulsion Module |
![](file.png) | RSN | Radio SuperNova |
![](file.png) | RTG | Radioisotope Thermoelectric Generator |
![](file.png) | RTLS | Return To Launch Site |
![](file.png) | RVSN | Raketniye Voiska Stratigcheskovo Naznacheniya |
![](file.png) | S | Spiral (for Galaxies) |
![](file.png) | S/C | SpaceCraft |
![](file.png) | SAA | South Atlantic Anomaly / Single Access Antenna |
![](file.png) | SAGA | Solar Array Gain Augmentation |
![](file.png) | SAIL | Shuttle Avionics Integration Laboratory |
![](file.png) | SAM | Shuttle Activation Monitor |
![](file.png) | SAMPEX | Solar Anomalous And Magnetospheric Particle EXplorer |
![](file.png) | SAMS | Space Acceleration Measurement System |
![](file.png) | SAO | Smithsonian Astrophysical Observatory |
![](file.png) | SAR | Search And Rescue / Synthetic Aperture Radar |
![](file.png) | SARA | Satellite Pour Astronomie Radio Amateur |
![](file.png) | SAREX | Search And Rescue Exercise / Shuttle Amateur Radio Experiment |
![](file.png) | SAS | Space Activity Suit / Space Adaptation Syndrome |
![](file.png) | SAT | Synthetic Aperture Telescope |
![](file.png) | SB | Spiral |