| AAAC | Astronomy and Astrophysics Advisory Committee |
| AAG | Astronomy and Astrophysics Research Grant |
| ACT | Atacama Cosmology Telescope |
| ACTA | Atmospheric erenkov Telescope Array |
| ACTpol | Atacama Cosmology Telescope polarization sensitive receiver |
| ADAP | Astrophysics Data Analysis Program |
| ADMX | Axion Dark Matter Experiment |
| AdvACT | Advanced Atacama Cosmology Telescope |
| AFTA | Astrophysics Focused Telescope Assets |
| AGILE | Astro-Rivelatore Gamma a Immagini Leggero |
| AGIS | Advanced Gamma ray Imaging System |
| ALMA | Atacama Large Millimeter Array |
| AMS | Alpha Magnetic Spectrometer |
| ANITA | Antarctic Impulse Transient Antenna |
| AO | Announcement of Opportunity |
| APOGEE | Apache Point Observatory Galactic Evolution Experiment |
| APRA | Astronomy and Physics Research and Analysis |
| APS | Astrophysical and Planetary Sciences |
| ARA | Askaryan Radio Array |
| ARIANNA | Antarctic Ross Iceshelf Antenna Neutrino Array |
| ART-XC | Astronomical Roentgen Telescope X-ray Concentrator |
| ASAS-SN | All Sky Automated Survey for Supernovae |
| ATI | Advanced Technologies and Instrumentation |
| ATP | Astrophysics Theory Program |
| AU | Astronomical Unit |
| AUI | Associated Universites, Inc. |
|
BAO |
baryon acoustic oscillation |
| BICEP | Background Imaging of Cosmic Extragalactic Polarization |
| BigBOSS | Big Baryon Oscillation Spectroscopic Survey |
| BOSS | Baryon Oscillation Spectroscopic Survey |
|
CAA |
Committee on Astronomy and Astrophysics |
| CALET | CALorimetric Electron Telescope |
| CARMA | Combined Array for Research in Millimeter-wave Astronomy |
| CASS | Cranfield Astrobiological Stratospheric Sampling |
| CATE | Cost and Technical Evaluation |
| CCAT | Cerro Chajnantor Atacama Telescope |
| CCD | charge-coupled device |
| CMB | Cosmic microwave background |
| CSO | Caltech Submillimeter Observatory |
| CTA | Cerenkov Telescope Array |
|
DES |
Dark Energy Survey |
| DESI | Dark Energy Spectroscopic Instrument |
| DKIST | Daniel K. Inouye Solar Telescope |
| DOE | Department of Energy |
| DRM | Design Reference Mission |
| DSIAC | Decadal Survey Implementation Advisory Committee |
|
EBEX |
E and B Experiment |
| eBOSS | Extended Baryon Oscillation Spectroscopic Survey |
| E-ELT | European Extremely Large Telescope |
| EHT | Event Horizon Telescope |
| eLISA | Evolved Laser Interferometer Space Antenna |
| ELT | Extremely Large Telescope |
| ESA | European Space Agency |
| ESO | European Southern Observatory |
|
FASR |
Frequency Agile Solar Radiotelescope |
| FAST | Fast Auroral Snapshot Explorer |
| FY | fiscal year |
| GBT | Green Bank Telescope |
| GMT | Giant Magellan Telescope |
| GO | Guest Observer |
| GSFC | Goddard Space Flight Center |
| GSMT | Giant Segmented Mirror Telescope |
| GUSTO | Gal/Xray U/LDB Spectroscopic Stratospheric Terahertz Observatory |
|
HAWC |
High-Altitude Water Cherenkov Observatory |
| HEPAP | High Energy Physics Advisory Panel |
| HERA | Hydrogen Epoch of Reionization Array |
| HESS | High Energy Stereoscopic System |
| HSC | Subaru Hyper-Suprime Camera |
| HST | Hubble Space Telescope |
|
IDRM |
Interim Design Reference Mission |
| IFU | integral field unit |
| IPTD | Inflation Probe Technology Development |
| ISG | Infrastructure Study Group |
| ISS | International Space Station |
| ISS-CREAM | ISS-Cosmic Ray Energetics and Mass |
| IXO | International X-ray Observatory |
|
JAXA |
Japan Aerospace Exploration Agency |
| JDEM-Omega | Joint Dark Energy Mission Omega |
| JUICE | JUpiter ICy moons Explorer |
| JVLA | Jansky Very Large Array (formerly the VLA) |
| JWST | James Webb Space Telescope |
|
KAGRA |
Kamioka Gravitational Wave Detector |
| KDP-A | Key Decision Point A |
| KPNO | Kitt Peak National Observatory |
|
LBO |
Long Baseline Observatory |
| LHC | Large Hadron Collider |
| LIGO | Advanced Laser Interferometry Gravitational-wave Observatory |
| LISA | Laser Interferometer Space Antenna |
| LiteBIRD | Light [Lite] satellite for the studies of B-mode polarization and Inflation from cosmic background Radiation Detection |
| LMT | Large Millimeter Telescope |
| LPF | LISA Pathfinder |
| LSST | Large Synoptic Survey Telescope |
| LTSA | Long Term Space Astrophysics |
| LUX-ZEPLIN | Large Underground Xenon-ZonEd Proportional scintillation in LIquid Noble gases |
|
MAGIC |
Major Atmospheric Gamma Imaging Cherenkov Observatory |
| MIDEX | Medium-Class Explorer |
| MoO | Mission of Opportunity |
| MREFC | Major Research Equipment and Facilities Construction |
| MSIP | Mid-Scale Innovations Program |
| MWA | Murchison Widefield Array |
|
NANOGrav |
North American Nanohertz Observatory for Gravitational Waves |
| NASA | National Aeronautics and Space Administration |
| NASA-APD | NASA Astrophysics Division |
| NICER | Neutron-star Interior Composition Explorer |
| NOAO | National Optical Astronomy Observatory |
| NRAO | National Radio Astronomy Observatory |
| NRC | National Research Council |
| NRO | National Reconnaissance Office |
| NSF | National Science Foundation |
| NSF-AST | NSF Division of Astronomical Sciences |
| NSF-PHY | NSF Division of Physics |
| NuSTAR | Nuclear Spectroscopic Telescope Array |
| NWNH | New Worlds, New Horizons |
| NWTD | New Worlds Technology Development |
|
OIR |
Optical and Infrared Astronomy |
| ORM | Roque de los Muchachos Observatory |
| OSS | Origins of Solar Systems |
|
P5 |
Particle Physics Project Prioritization Panel |
| PAMELA | Payload for Antimatter/Matter Exploration and Light-nuclei Astrophysics |
| Pan-STARRS | Panoramic Survey Telescope and Rapid Response System |
| PAPER | Precision Array to Probe Epoch of Reionization |
| PI | principal investigator |
| PIPER | Primordial Inflation Polarization Explorer |
| PPP | Project Prioritization Panels |
| PRAXyS | Polarimeter for Relativistic Astrophysical X-ray Sources |
| PTF | Palomar Transient Factory |
|
ReSTAR |
Renewing Small Telescopes |
| RFI | Request for Information |
|
SAT |
Strategic Astrophysics Technology |
| SDSS | Sloan Digital Sky Survey |
| SDT | Science Definition Team |
| SFP | Science Frontier Panel |
| SKA | Square Kilometer Array |
| SMEX | Small Explorer |
| SOFIA | Stratospheric Observatory for Infrared Astronomy |
| SPHEREx | all-sky near IR spectral survey |
| SPICA | Space Infrared Telescope for Cosmology and Astrophysics |
| SPT | South Pole Telescope |
| SPT3G | South Pole Telescope 3rd Generation |
| SPTpol | South Pole Telescope polarization instrument |
| SQUID | Superconducting Quantum Interference Devices |
| Super-CDMS | Super Cryogenic Dark Matter Search |
| Super-TIGER | Super Trans-Iron Galactic Element Recorder |
|
TA |
Telescope Array |
| TCAN | Theoretical and Computational Astrophysics Networks |
| TESS | Transiting Exoplanet Survey Satellite |
| TMT | Thirty Meter Telescope |
| TRL | technology readiness level |
| TSIP | Telescope Systems Instrumentation Program |
|
URO |
University Radio Observatories |
| UV | ultraviolet |
|
VERITAS |
Very Energetic Radiation Imaging Telescope Array System |
| VLA | Very Large Array |
| VLBA | Very Long Baseline Array |
| VLT | Very Large Telescope |
|
WFC3 |
Wide Field Camera 3 |
| WFIRST | Wide-Field Infrared Survey Telescope |
| WIMP | weakly interacting massive particle |
| WIYN | Wisconsin/Indiana/Yale/NOAO Telescope |
| WMAP | Wilkinson Microwave Anisotropy Probe |
|
XMM |
NASA’s X-ray Multi-Mirror Mission |
| XMM-Newton | European Space Agency’s X-ray Multi-Mirror Mission |
| XRP | Exoplanet Research Program (formerly OSS) |