| Acronym | Meaning |
![](file.png) | A&A | Astronomy And Astrophysics |
![](file.png) | AACS | Attitude And Articulation Control Subsystem |
![](file.png) | AAO | Anglo-Australian Observatory |
![](file.png) | AAS | American Astronomical Society |
![](file.png) | AAS | American Astronautical Society |
![](file.png) | AAVSO | American Association Of Variable Star Observers |
![](file.png) | AC | Atlas Centaur |
![](file.png) | ACE | Advanced Composition Explorer |
![](file.png) | ACF | Automated Control Function |
![](file.png) | ACR | Active Cavity Radiometer |
![](file.png) | ACRIM | ACR Irradiance Monitor |
![](file.png) | ACRV | Assured Crew Return Vehicle |
![](file.png) | ACRV | Astronaut Crew Rescue Vehicle |
![](file.png) | ACTS | Advanced Communications Technology Satellite |
![](file.png) | ADEOS | Advanced Earth Observing Satellite |
![](file.png) | ADFRF | Ames-Dryden Flight Research Facility |
![](file.png) | ADS | Astrophysical Data System (at Havard-Smithsonian CfA) |
![](file.png) | ADS | Aitken Double Star Catalog |
![](file.png) | AE | Arianespace SA |
![](file.png) | AEPI | Atmospheric Emissions Photometric Imaging |
![](file.png) | AF | Air Force |
![](file.png) | AFETR | USAF's ETR |
![](file.png) | AFGWC | Air Force Global Weather Center |
![](file.png) | AFP | Air Force Program |
![](file.png) | AFPRO | Air Force Plan Representative Office |
![](file.png) | AFRSI | Advanced FRSI |
![](file.png) | AFWTR | USAF's WTR |
![](file.png) | AGB | Asymptotic Giant Branch |
![](file.png) | AGE | Auxiliary Ground Equipment |
![](file.png) | AGN | Active Galactic Nucleus |
![](file.png) | AGU | American Geophysical Union |
![](file.png) | AIAA | American Institute Of Aeronautics And Astronautics |
![](file.png) | AIPS | Astronomical Image Processing System |
![](file.png) | AIRS | Atmospheric Infrared Sounder |
![](file.png) | AJ | Astronomical Journal |
![](file.png) | ALAE | Atmospheric Lyman-Alpha Emissions |
![](file.png) | ALDP | Advanced Launch Development Program |
![](file.png) | ALEXIS | Array Of Low Energy X-ray Imaging Sensors |
![](file.png) | ALPO | Association Of Lunar And Planetary Observers |
![](file.png) | ALS | Advanced Launch System |
![](file.png) | AMOS | Air Force Maui Optical System |
![](file.png) | AMSR | Advanced Microwave Sounding Radiometer |
![](file.png) | ANSI | American National Standards Institute |
![](file.png) | AOA | Abort Once Around (shuttle Abort Plan) |
![](file.png) | AOA | Angle Of Attack |
![](file.png) | AOCS | Attitude And Orbit Control System |
![](file.png) | APE | Auroral Photography Experiment |
![](file.png) | APJ | Astrophysical Journal |
![](file.png) | APL | Applied Physics Laboratory (at Johns Hopkins) |
![](file.png) | APM | Attached Pressurized Module (a.k.a. Columbus) |