| Acronym | Meaning |
 | GOMOS | Global Ozone Monitoring By Occultation Of Stars |
 | GOMR | Global Ozone Monitoring Radiometer |
 | GOSAMR | Gelation Of Soils: Applied Microgravity Research |
 | GOX | Gaseous OXygen |
 | GPC | General Purpose Computer |
 | GPPF | Gravitational Plant Physiology Facility |
 | GPS | Global Positioning System |
 | GR | General Relativity |
 | GRO | Gamma Ray Observatory |
 | GRS | Gamma Ray Spectrometer |
 | GRS | Great Red Spot |
 | GRTLS | Glide RTLS |
 | GRU | Glavnoye Razvedivatel'noye Upravileniye |
 | GSC | Guide Star Catalog |
 | GSFC | Goddard Space Flight Center |
 | GSO | GeoSynchronous Earth Orbit |
 | GST | Greenwich Sidereal Time |
 | GTO | Geostationary Transfer Orbit |
 | GUGK | Glavnoye Upravileniye Geodesii I Kartografii |
 | HAINS | High Accuracy Inertial Navigation System |
 | HALOE | Halogen Occultation Experiment |
 | HAO | High Altitude Observatory |
 | HB | Horizontal Branch |
 | HCI | Highes Communications |
 | HCMM | Heat Capacity Mapping Mission |
 | HD | Henry Draper Catalog Entry |
 | HDE | Henry Draper Extension |
 | HDM | Hot Dark Matter |
 | HEAO | High Energy Astronomical Observatory |
 | HERA | Hermes Robotic Arm |
 | HF | High Frequency |
 | HGA | High Gain Antenna |
 | HH | Hitchhiker |
 | HIRDLS | High Resolution Dynamics Limb Sounder |
 | HIRIS | High Resolution Imaging Spectrometer |
 | HIRS | High Resolution Infrared Radiation Sounder |
 | HJD | Helicentric Julian Date |
 | HLC | Heavy Lift Capability |
 | HLV | Heavy Lift Vehicle |
 | HMC | Halley Multicolor Camera |
 | HOTOL | HOrizontal TakeOff And Landing |
 | HPFTP | High Pressure Fuel Turbopump |
 | HPOTP | High Pressure Oxidizer Turbopump |
 | HR | Hertzsprung-Russell |
 | HRDI | High Resolution Doppler Imager |
 | HRI | High Resolution Imager |
 | HRMS | High Resolution Microwave Survey |
 | HRPT | High Resolution Picture Transmission |
 | HRSC | High Resolution Stereo Camera |
 | HRSI | High-temperature Reusable Surface Insulation |