Archive-name: space/acronyms
Acronym List for Space and Astronomy
As of 2009 April 14
This list is offered as a reference for translating commonly appearing acronyms in the space-related newsgroups. If I forgot or botched your favorite acronym, please let me know! Also, if there's an acronym not on this list that confuses you, drop me a line, and if I can figure it out, I'll add it to the list.
The canonical version of this list is the HTML form, available at http://tla.surly.org/ . From that, I generate the text form for USENET posting.
Note that this is intended to be a reference for frequently seen acronyms, and is most emphatically not encyclopedic. If I incorporated every acronym I ever saw, I'd soon run out of disk space. :-)
The list will be posted at regular intervals, every 30 days. All comments regarding it are welcome; I'm reachable at tla@surly.org. NOTE: Due to the high level of spam I receive, you must include the text "tla" in the Subject header of your e-mail, or I will never see your message.
Note that this list just tells what the acronyms stand for -- you're on your own for figuring out what they mean. Note also that the total number of acronyms in use far exceeds what I can list; special-purpose acronyms that are essentially always explained as they're introduced are omitted. Further, some acronyms stand for more than one thing; these acronyms appear on multiple lines.
Thanks to everybody who's sent suggestions since the first version of the list!
PS: Strictly speaking, most of these are "initialisms" or "abbreviations" rather than "acronyms"; pedantically, it's only an "acronym" if you make a word out of it, like "laser" or "radar." In practice, though, everybody calls 'em acronyms.
| A&A: | Astronomy and Astrophysics |
| AAO: | Anglo-Australian Observatory |
| AAS: | American Astronomical Society |
| AAS: | American Astronautical Society |
| AAVSO: | American Association of Variable Star Observers |
| ACE: | Advanced Composition Explorer |
| ACRV: | Assured Crew Return Vehicle (or) Astronaut Crew Rescue Vehicle |
| AD: | Analog to Digital |
| ADFRF: | Ames-Dryden Flight Research Facility (now DFRC) (NASA) |
| AFAIK: | As Far As I Know |
| AGN: | Active Galactic Nucleus |
| AGU: | American Geophysical Union |
| AIAA: | American Institute of Aeronautics and Astronautics |
| AIPS: | Astronomical Image Processing System |
| AIT: | Assembly, Integration, and Testing |
| AJ: | Astronomical Journal |
| ALEXIS: | Array of Low Energy X-ray Imaging Sensors |
| ALPO: | Association of Lunar and Planetary Observers |
| ALS: | Advanced Launch System |
| ANSI: | American National Standards Institute |
| AOA: | Abort Once Around (Shuttle abort plan) |
| AOA: | Angle Of Attack |
| AOCS: | Attitude and Orbit Control System |
| Ap.J: | Astrophysical Journal |
| APL: | Applied Physics Laboratory (at Johns Hopkins) |
| APM: | Attached Pressurized Module (a.k.a. Columbus) |
| APU: | Auxiliary Power Unit |
| ARC: | Ames Research Center (NASA) |
| ARC: | Astrophysical Research Consortium |
| ARTEMIS: | Advanced Relay TEchnology MISsion |
| ASA: | Astronomical Society of the Atlantic |
| ASC: | Agence Spatiale Canadienne (also CSA) |
| ASI: | Agenzia Spaziale Italiana |
| ASP: | Astronomical Society of the Pacific |
| ASRM: | Advanced Solid Rocket Motor |
| ATDRS: | Advanced Tracking and Data Relay Satellite |
| ATLAS: | Atmospheric Laboratory for Applications and Science |
| ATM: | Amateur Telescope Maker |
| ATM: | Apollo Telescope Mount (on Skylab) |
| ATO: | Abort To Orbit |
| ATV: | Automated Transfer Vehicle |
| AU: | Astronomical Unit |
| AURA: | Association of Universities for Research in Astronomy |
| AW&ST: | Aviation Week and Space Technology (a.k.a. AvLeak) |
| AXAF: | Advanced X-ray Astrophysics Facility |
| BAe: | British Aerospace (now BAE SYSTEMS) |
| BATSE: | Burst And Transient Source Experiment (on CGRO) |
| BBXRT: | Broad-Band X-Ray Telescope (ASTRO package) |
| BDB: | Big Dumb Booster |
| BEM: | Bug-Eyed Monster |
| BH: | Black Hole |
| BIMA: | Berkeley Illinois Maryland Array |
| BIS: | British Interplanetary Society |
| BMDO: | Ballistic Missile Defense Office (was SDIO) |
| BNSC: | British National Space Centre |
| BTW: | By The Way |
| CARA: | Center for Astrophysical Research in Antarctica |
| C&T: | Communications & Tracking |
| CATS: | Cheap Access To Space |
| CCAFS: | Cape Canaveral Air Force Station |
| CCAS: | Cape Canaveral Air Station (now once again CCAFS) |
| CCD: | Charge-Coupled Device |
| CCDS: | Centers for the Commercial Development of Space |
| CD-ROM: | Compact Disc Read-Only Memory |
| CFA: | Center For Astrophysics |
| CFC: | ChloroFluoroCarbon |
| CFF: | Columbus Free Flyer |
| CFHT: | Canada-France-Hawaii Telescope |
| CFIT: | Controlled Flight Into Terrain |
| CG: | Center of Gravity |
| CGRO: | (Arthur Holley) Compton Gamma Ray Observatory (was GRO) |
| CHARA: | Center for High Angular Resolution Astronomy |
| CIRRIS: | Cryogenic InfraRed Radiance Instrument for Shuttle |
| CIT: | Circumstellar Imaging Telescope |
| CM: | Command Module (Apollo spacecraft) |
| CM: | Center of Mass |
| CMBR: | Cosmic Microwave Background Radiation |
| CMCC: | Central Mission Control Centre (ESA) |
| CNES: | Centre National d'Etude Spatiales |
| CNO: | Carbon-Nitrogen-Oxygen |
| CNSR: | Comet Nucleus Sample Return |
| COBE: | COsmic Background Explorer |
| COMPTEL: | COMPton TELescope (on CGRO) |
| COSTAR: | Corrective Optics Space Telescope Axial Replacement |
| COTS: | Commercial (or Cheap) Off The Shelf |
| CRAF: | Comet Rendezvous / Asteroid Flyby |
| CRRES: | Combined Release / Radiation Effects Satellite |
| CSA: | Canadian Space Agency (also ASC) |
| CSM: | Command and Service Module (Apollo spacecraft) |
| CSTC: | Consolidated Space Test Center (USAF) |
| CTB: | Cargo Transfer Bag |
| CTIO: | Cerro Tololo Interamerican Observatory |
| CV: | Cataclysmic Variable |
| CXBR: | Cosmic X-ray Background Radiation |
| DC: | Delta Clipper |
| DCX: | Delta Clipper eXperimental |
| DDCU: | DC-to-DC Converter Unit |
| DDTE: | Design, Development, Test, and Evaluation |
| DFRC: | Dryden Flight Research Center |
| DFRF: | Dryden Flight Research Facility (was ADFRF, now DFRC) |
| DMSP: | Defense Meteorological Satellite Program |
| DOD: | Department Of Defense (sometimes DoD) |
| DOE: | Department Of Energy |
| DOT: | Department Of Transportation |
| DRS: | Data Relay Satellite |
| DRS: | Direct Receiving Station |
| DSO: | Deep Sky (or Space) Object |
| DSCS: | Defense Satellite Communications System |
| DSN: | Deep Space Network |
| DSP: | Defense Support Program (USAF/NRO) |
| EAC: | European Astronaut Centre |
| EAFB: | Edwards Air Force Base |
| ECS: | Environmental Control System |
| EDO: | Extended Duration Orbiter |
| EGRET: | Energetic Gamma Ray Experiment Telescope (on CGRO) |
| EJASA: | Electronic Journal of the Astronomical Society of the Atlantic |
| ELV: | Expendable Launch Vehicle |
| EMU: | Extravehicular Mobility Unit |
| EOS: | Earth Observing System |
| ER: | Eastern Range (was ETR) |
| ERS: | Earth Resources Satellite (as in ERS-1) |
| ESA: | European Space Agency |
| ESIS: | European Space Information System |
| ESO: | European Southern Observatory |
| ESOC: | European Space Operations Centre |
| ESTEC: | European Space Research & Technology Centre |
| ET: | (Shuttle) External Tank |
| ETLA: | Extended Three Letter Acronym |
| ETR: | Eastern Test Range |
| EUV: | Extreme UltraViolet |
| EUVE: | Extreme UltraViolet Explorer |
| EVA: | ExtraVehicular Activity |
| FAQ: | Frequently Asked Questions |
| FAST: | Fast Auroral SnapshoT explorer |
| FFT: | Fast Fourier Transform |
| FGS: | Fine Guidance Sensors (on HST) |
| FHST: | Fixed Head Star Trackers (on HST) |
| FIR: | Far InfraRed |
| FITS: | Flexible Image Transport System |
| FOC: | Faint Object Camera (on HST) |
| FOS: | Faint Object Spectrograph (on HST) |
| FOV: | Field Of View |
| FRC: | Flight Research Center (old name for DFRC) |
| FRR: | Flight-Readiness Review |
| FTETTM: | From The Earth To The Moon |
| FTL: | Faster Than Light |
| FTP: | File Transfer Protocol |
| FTS: | Flight Telerobotic Servicer |
| FUSE: | Far Ultraviolet Spectroscopic Explorer |
| FWHM: | Full Width at Half Maximum |
| FYI: | For Your Information |
| G: | Gravity |
| GAS: | Get-Away Special |
| GBT: | Green Bank Telescope |
| GCVS: | General Catalog of Variable Stars |
| GEM: | Giotto Extended Mission |
| GEM: | Galileo Europa Mission |
| GEO: | Geosynchronous Earth Orbit |
| GDS: | Great Dark Spot |
| GHRS: | Goddard High Resolution Spectrograph (on HST) |
| GIF: | Graphics Interchange Format |
| GLOMR: | Global Low-Orbiting Message Relay |
| GLOW: | Gross Lift-Off Weight |
| GMC: | Giant Molecular Cloud |
| GMRT: | Giant Meter-wave Radio Telescope |
| GMT: | Greenwich Mean Time (also called UT) |
| GOES: | Geostationary Orbiting Environmental Satellite |
| GOX: | Gaseous OXygen |
| GPC: | General Purpose Computer |
| GPS: | Global Positioning System |
| GR: | General Relativity |
| GRB: | Gamma Ray Burster |
| GRC: | Glenn Research Center (NASA) |
| GRO: | Gamma Ray Observatory (now CGRO) |
| GRS: | Gamma Ray Spectrometer (on Mars Observer) |
| GRS: | Great Red Spot |
| GSC: | Guide Star Catalog (for HST) |
| GSFC: | Goddard Space Flight Center (NASA) |
| GTO: | Geostationary Transfer Orbit |
| GVI: | Global Village Idiot |
| HAO: | High Altitude Observatory |
| HD: | Henry Draper catalog entry |
| HEAO: | High Energy Astronomical Observatory |
| HeRA: | Hermes Robotic Arm |
| HF: | High Frequency |
| HGA: | High Gain Antenna |
| HLC: | Heavy Lift Capability |
| HLV: | Heavy Lift Vehicle |
| HMC: | Halley Multicolor Camera (on Giotto) |
| HOTOL: | HOrizontal TakeOff and Landing (a proposed SSTO craft) |
| HR: | Hertzsprung-Russell (diagram) |
| HRMS: | High Resolution Microwave Survey |
| HRI: | High Resolution Imager (on ROSAT) |
| HSP: | High Speed Photometer (on HST) |
| HST: | Hubble Space Telescope |
| HTH: | Hope This Helps |
| HTHL: | Horizontal Takeoff Horizontal Landing |
| HTVL: | Horizontal Takeoff Vertical Landing |
| HUT: | Hopkins Ultraviolet Telescope (ASTRO package) |
| HV: | High Voltage |
| IAPPP: | International Amateur/Professional Photoelectric Photometry |
| IAU: | International Astronomical Union |
| IAUC: | IAU Circular |
| ICE: | International Cometary Explorer |
| IDA: | International Dark-sky Association |
| IDL: | Interactive Data Language |
| IGM: | InterGalactic Medium |
| IGY: | International Geophysical Year |
| IIRC: | If I Recall Correctly |
| IMHO: | In My Humble Opinion |
| IMO: | International Meteor Organization |
| INTEGRAL: | INTErnational Gamma-Ray Astrophysics Laboratory |
| IOTA: | Infrared-Optical Telescope Array |
| IOTA: | International Occultation Timing Association |
| IPS: | Inertial Pointing System |
| IR: | InfraRed |
| IRAF: | Image Reduction and Analysis Facility |
| IRAS: | InfraRed Astronomical Satellite |
| IRFNA: | Inhibited Red Fuming Nitric Acid |
| ISAS: | Institute of Space and Astronautical Science (Japan) |
| ISM: | InterStellar Medium |
| ISO: | Infrared Space Observatory |
| ISO: | International Standards Organization |
| ISPM: | International Solar Polar Mission (now Ulysses) |
| ISPP: | In-Situ Propellant Production |
| ISS: | International Space Station |
| ISY: | International Space Year |
| IUE: | International Ultraviolet Explorer |
| IUS: | Inertial Upper Stage |
| JEM: | Japanese Experiment Module (for SSF) |
| JGR: | Journal of Geophysical Research |
| JILA: | Joint Institute for Laboratory Astrophysics |
| JPL: | Jet Propulsion Laboratory |
| JSC: | Johnson Space Center (NASA) |
| KAO: | Kuiper Airborne Observatory |
| KPNO: | Kitt Peak National Observatory |
| KSC: | Kennedy Space Center (NASA) |
| KTB: | Cretaceous-Tertiary Boundary (from German) |
| L: | Lagrange (as in Lagrange points L1 through L5) |
| LANL: | Los Alamos National Laboratory |
| LaRC: | Langley Research Center (NASA) |
| LASER: | Light Amplification by Stimulated Emission of Radiation |
| LDEF: | Long Duration Exposure Facility |
| LEM: | Lunar Excursion Module (a.k.a. LM) (Apollo spacecraft) |
| LEO: | Low Earth Orbit |
| LeRC: | Lewis Research Center (NASA; now GRC) |
| LEST: | Large Earth-based Solar Telescope |
| LFSA: | List of Frequently Seen Acronyms (!) |
| LGA: | Low Gain Antenna |
| LGM: | Little Green Men |
| LH: | Liquid Hydrogen (also LH2 or LHX) |
| LITVC: | Liquid Injection Thrust Vector Control |
| LLNL: | Lawrence-Livermore National Laboratory |
| LM: | Lunar Module (a.k.a. LEM) (Apollo spacecraft) |
| LMC: | Large Magellanic Cloud |
| LN2: | Liquid N2 (Nitrogen) |
| LOX: | Liquid OXygen |
| LPO: | La Palma Observatory |
| LPV: | Long Period Variable |
| LRB: | Liquid Rocket Booster |
| LSR: | Local Standard of Rest |
| LTP: | Lunar Transient Phenomenon |
| M: | Messier (as in M31, M13, M57, etcetera) |
| MACRO: | Monopoles, Astrophysics, and Cosmic Ray Observatory |
| MB: | Manned Base |
| MCC: | Mission Control Center |
| MCD: | Minimum Cost Design |
| MCO: | Mars Climate Orbiter |
| MECO: | Main Engine CutOff |
| MERIS: | Medium Resolution Imaging Spectrometer |
| MGS: | Mars Global Surveyor |
| MHD: | MagnetoHydroDynamic |
| MLI: | Multi-Layer Insulation |
| MMH: | MonoMethyl Hydrazine |
| MMT: | Multiple Mirror Telescope |
| MMU: | Manned Maneuvering Unit |
| MNRAS: | Monthly Notices of the Royal Astronomical Society |
| MO: | Mars Observer |
| MOC: | Mars Observer Camera (on MO and MGS) |
| MODIS: | Moderate Resolution Imaging Spectroradiometer |
| MOL: | Manned Orbiting Laboratory |
| MOLA: | Mars Observer Laser Altimeter (on Mars Observer) |
| MOMV: | Manned Orbital Maneuvering Vehicle |
| MOTV: | Manned Orbital Transfer Vehicle |
| MPC: | Minor Planets Circular |
| MPEC: | Minor Planets Electronic Circular |
| MPL: | Mars Polar Lander |
| MRSR: | Mars Rover and Sample Return |
| MRSRM: | Mars Rover and Sample Return Mission |
| MSFC: | (George C.) Marshall Space Flight Center (NASA) |
| MTC: | Man Tended Capability |
| NACA: | National Advisory Committee on Aeronautics (became NASA) |
| NASA: | National Aeronautics and Space Administration |
| NASDA: | NAtional Space Development Agency (Japan) |
| NASM: | National Air and Space Museum |
| NASP: | National AeroSpace Plane |
| NBS: | National Bureau of Standards (now NIST) |
| NDV: | NASP Derived Vehicle |
| NEAR: | Near Earth Asteroid Rendezvous (now named NEAR Shoemaker) |
| NERVA: | Nuclear Engine for Rocket Vehicle Application |
| NG: | NewsGroup |
| NGC: | New General Catalog |
| NGST: | Next Generation Space Telescope |
| NICMOS: | Near Infrared Camera / Multi Object Spectrometer (HST upgrade) |
| NIMS: | Near-Infrared Mapping Spectrometer (on Galileo) |
| NIR: | Near InfraRed |
| NIST: | National Institute of Standards and Technology (was NBS) |
| NLDP: | National Launch Development Program |
| NOAA: | National Oceanic and Atmospheric Administration |
| NOAO: | National Optical Astronomy Observatories |
| NORAD: | NORth American aerospace Defense |
| NRAO: | National Radio Astronomy Observatory |
| NRO: | National Reconnaissance Office |
| NS: | Neutron Star |
| NSA: | National Security Agency |
| NSF: | National Science Foundation |
| NSO: | National Solar Observatory |
| NSSDC: | National Space Science Data Center |
| NTR: | Nuclear Thermal Rocket(ry) |
| NTT: | New Technology Telescope |
| OAO: | Orbiting Astronomical Observatory |
| OCST: | Office of Commercial Space Transportation |
| OMB: | Office of Management and Budget |
| OMS: | Orbital Maneuvering System |
| OPF: | Orbiter Processing Facility |
| ORFEUS: | Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer |
| OSC: | Orbital Sciences Corporation |
| OSCAR: | Orbiting Satellite Carrying Amateur Radio |
| OSSA: | Office of Space Science and Applications |
| OSSE: | Oriented Scintillation Spectrometer Experiment (on CGRO) |
| OT: | Off-Topic |
| OTA: | Optical Telescope Assembly (on HST) |
| OTHB: | Over The Horizon Backscatter |
| OTV: | Orbital Transfer Vehicle |
| OV: | Orbital Vehicle |
| PAM: | Payload Assist Module |
| PAM-D: | Payload Assist Module, Delta-class |
| PDS: | Planetary Data System |
| PI: | Principal Investigator |
| PLSS: | Portable Life Support System |
| PM: | Pressurized Module |
| PMC: | Permanently Manned Capability |
| PMIRR: | Pressure Modulated InfraRed Radiometer (on Mars Observer) |
| PMT: | PhotoMultiplier Tube |
| PPM: | Positions and Proper Motions (catalog) |
| PSF: | Point Spread Function |
| PSR: | PulSaR |
| PV: | Photovoltaic |
| PVO: | Pioneer Venus Orbiter |
| QSO: | Quasi-Stellar Object |
| RADAR: | RAdio Detection And Ranging |
| RAS: | Royal Astronomical Society |
| RASC: | Royal Astronomical Society of Canada |
| RCI: | Rodent Cage Interface (for SLS mission) |
| RCS: | Radar Cross Section |
| RCS: | Reaction Control System |
| REM: | Rat Enclosure Module (for SLS mission) |
| RF: | Radio Frequency |
| RFI: | Radio Frequency Interference |
| RFNA: | Red Fuming Nitric Acid |
| RIACS: | Research Institute for Advanced Computer Science |
| RMS: | Remote Manipulator System |
| RNGC: | Revised New General Catalog |
| ROTFL: | Rolling On The Floor Laughing |
| ROSAT: | ROentgen SATellite |
| ROUS: | Rodents Of Unusual Size (I don't believe they exist) |
| RSA: | Russian Space Agency |
| RSN: | Radio SuperNova |
| RSN: | Real Soon Now |
| RTG: | Radioisotope Thermoelectric Generator |
| RTLS: | Return To Launch Site (Shuttle abort plan) |
| SAA: | South Atlantic Anomaly |
| SAGA: | Solar Array Gain Augmentation (for HST) |
| SAMPEX: | Solar Anomalous and Magnetospheric Particle EXplorer |
| SAO: | Smithsonian Astrophysical Observatory |
| SAR: | Search And Rescue |
| SAR: | Synthetic Aperture Radar |
| SARA: | Satellite pour Astronomie Radio Amateur |
| SAREX: | Search and Rescue Exercise |
| SAREX: | Space Amateur Radio Experiment |
| SAS: | Space Activity Suit |
| SAS: | Space Adaptation Syndrome |
| SAT: | Synthetic Aperture Telescope |
| S/C: | SpaceCraft |
| SCA: | Shuttle Carrier Aircraft |
| SCT: | Schmidt-Cassegrain Telescope |
| SDI: | Strategic Defense Initiative |
| SDIO: | Strategic Defense Initiative Organization (now BMDO) |
| SEDS: | Students for the Exploration and Development of Space |
| SEI: | Space Exploration Initiative |
| SEST: | Swedish ESO Submillimeter Telescope |
| SETI: | Search for ExtraTerrestrial Intelligence |
| SID: | Sudden Ionospheric Disturbance |
| SIR: | Shuttle Imaging Radar |
| SIRTF: | Space (formerly Shuttle) InfraRed Telescope Facility |
| SL: | (Comet) Shoemaker-Levy |
| SL: | SpaceLab |
| SLAR: | Side-Looking Airborne Radar |
| SLC: | Space Launch Complex |
| SLS: | Space(lab) Life Sciences |
| SMC: | Small Magellanic Cloud |
| SME: | Solar Mesosphere Explorer |
| SMEX: | SMall EXplorers |
| SMM: | Solar Maximum Mission |
| SN: | SuperNova (e.g., SN1987A) |
| SNR: | Signal to Noise Ratio |
| SNR: | SuperNova Remnant |
| SNU: | Solar Neutrino Units |
| SOFIA: | Stratospheric Observatory For Infrared Astronomy |
| SOHO: | SOlar Heliospheric Observatory |
| SPAN: | Space Physics and Analysis Network |
| SPDM: | Special Purpose Dextrous Manipulator |
| SPOT: | Satellite Pour l'Observation de la Terre |
| SPS: | Solar Power Satellite |
| SR: | Special Relativity |
| SRB: | Solid Rocket Booster |
| SRM: | Solid Rocket Motor |
| SSF: | Space Station Fred (er, Freedom) (Superseded by ISS) |
| SSI: | Solid-State Imager (on Galileo) |
| SSI: | Space Studies Institut |
| SSME: | Space Shuttle Main Engine |
| SSPF: | Space Station Processing Facility |
| SSPS: | Sky Survey Prototype System |
| SSRMS: | Space Station Remote Manipulator System |
| SSRT: | Single Stage Rocket Technology |
| SST: | Spectroscopic Survey Telescope |
| SST: | SuperSonic Transport |
| SSTO: | Single Stage To Orbit |
| STIS: | Space Telescope Imaging Spectrometer (to replace FOC and GHRS) |
| STS: | Shuttle Transport System (or) Space Transportation System |
| STScI: | Space Telescope Science Institute |
| STSDAS: | Space Telescope Science Data Analysis System |
| SWAS: | Submillimeter Wave Astronomy Satellite |
| SWF: | ShortWave Fading |
| TAL: | Transatlantic Abort Landing (Shuttle abort plan) |
| TANSTAAFL: | There Ain't No Such Thing As A Free Lunch |
| TAU: | Thousand Astronomical Unit (mission) |
| TCS: | Thermal Control System |
| TDRS: | Tracking and Data Relay Satellite |
| TDRSS: | Tracking and Data Relay Satellite System |
| TEA: | Torque Equilibrium Attitude |
| TES: | Thermal Emission Spectrometer (on Mars Observer) |
| THEMIS: | THermal EMission Imaging System (on Mars 2001 Odyssey) |
| TIROS: | Television InfraRed Observation Satellite |
| TLA: | Three Letter Acronym |
| TOMS: | Total Ozone Mapping Spectrometer |
| TOPS: | Toward Other Planetary Systems |
| TPS: | Thermal Protection System |
| TSS: | Targeted Search System |
| TSS: | Tethered Satellite System |
| TSTO: | Two Stage To Orbit (also 2STO) |
| UARS: | Upper Atmosphere Research Satellite |
| UBM: | Unpressurized Berthing Mechanism |
| UDMH: | Unsymmetrical DiMethyl Hydrazine |
| UFO: | Unidentified Flying Object |
| UGC: | Uppsala General Catalog |
| UHF: | Ultra High Frequency |
| UIT: | Ultraviolet Imaging Telescope (Astro package) |
| UKST: | United Kingdom Schmidt Telescope |
| USAF: | United States Air Force |
| USMP: | United States Microgravity Payload |
| USNO: | United States Naval Observatory |
| UT: | Universal Time (a.k.a. GMT, or Zulu Time; cf UTC) |
| UTC: | Coordinated Universal Time (subtly different from UT) |
| UV: | UltraViolet |
| UVS: | UltraViolet Spectrometer |
| VAB: | Vehicle Assembly Building (formerly Vertical Assembly Building) |
| VAFB: | Vandenberg Air Force Base |
| VEEGA: | Venus-Earth-Earth Gravity Assist (Galileo flight path) |
| VHF: | Very High Frequency |
| VLA: | Very Large Array |
| VLBA: | Very Long Baseline Array |
| VLBI: | Very Long Baseline Interferometry |
| VLF: | Very Low Frequency |
| VLT: | Very Large Telescope |
| VMS: | Vertical Motion Simulator |
| VOIR: | Venus Orbiting Imaging Radar (superseded by VRM) |
| VPF: | Vertical Processing Facility |
| VRM: | Venus Radar Mapper (now called Magellan) |
| VTHL: | Vertical Takeoff Horizontal Landing |
| VTVL: | Vertical Takeoff Vertical Landing |
| WD: | White Dwarf |
| WFF: | Wallops Flight Facility |
| WFPC: | Wide Field / Planetary Camera (on HST) |
| WFPCII: | Replacement for WFPC |
| WIYN: | Wisconsin / Indiana / Yale / NOAO telescope |
| WR: | Western Range (was WTR) |
| WSF: | Wake Shield Facility |
| WSMR: | White Sands Missile Range |
| WTR: | Western Test Range |
| WUPPE: | Wisconsin Ultraviolet PhotoPolarimter Experiment (Astro package) |
| XMM: | X-ray Multi Mirror |
| XUV: | eXtreme UltraViolet |
| YSO: | Young Stellar Object |
| Z: | Zulu (see UT) |