| Acronym | Meaning |
 | EUV | Extreme UltraViolet |
 | EUVE | Extreme UltraViolet Explorer |
 | EVA | Extravehicular Activity |
 | FAP | Freedom Attached Payloads |
 | FAST | Fast Auroral SnapshoT Explorer |
 | FBV | Fuel Bleed Valve |
 | FEM | Flight-Engineering Model |
 | FFCC | Free-Flyer Control Centre |
 | FFT | Fast Fourier Transform |
 | FGS | Fine Guidance Sensors |
 | FHST | Fixed Head Star Trackers |
 | FIR | Far InfraRed |
 | FIRAS | Far InfraRed Absolute Spectrophotometer |
 | FITS | Flexible Image Transport System |
 | FOC | Faint Object Camera |
 | FOLD | Federally-Owned LANDSAT Data |
 | FOS | Faint Object Spectrograph |
 | FPD | Flight Projects Directorate |
 | FPM | Fiber Pulling In Microgravity |
 | FRC | Flight Research Center |
 | FRED | Space Station Freedom |
 | FRF | Flight Readiness Firing |
 | FRR | Flight-Readiness Review |
 | FRSI | Flexible Reusable Surface Insulation |
 | FTS | Flight Telerobotic Servicer |
 | FUSE | Far Ultraviolet Spectroscopic Explorer |
 | FWHM | Full Width At Half Maximum |
 | GAS | Get-Away Special |
 | GBT | Green Bank Telescope |
 | GC | Galactic Center |
 | GC | Globular Cluster |
 | GCVS | General Catalog Of Variable Stars |
 | GDCLS | General Dynamics Commercial Launch Services |
 | GDS | Great Dark Spot |
 | GEM | Giotto Extended Mission |
 | GEM | Graphite Epoxy Motor |
 | GEO | Geosynchronous Earth Orbit |
 | GEODSS | Ground-based Electro-optical Deep-space Surveillance System |
 | GGM | Goskogidromet/Gidromettsentr |
 | GHA | Greenwich Hour Angle |
 | GHRS | Goddard High Resolution Spectrograph |
 | GIF | Graphics Interchange Format |
 | GISS | Goddard Institute For Space Studies |
 | GLOMR | Global Low-Orbiting Message Relay |
 | GMC | Giant Molecular Cloud |
 | GMRT | Giant Meter-wave Radio Telescope |
 | GMS | Geostationary Meterological Satellite |
 | GMT | Greenwich Mean Time |
 | GNC | Guidance |
 | GOES | Geostationary Orbiting Environmental Satellite |