G
- G – (catalog) Giclas, a catalog of nearby stars
- GAIA – (telescope) Global Astrometric Interferometer for Astrophysics, a planned space telescope that will be used to make high-precision measurements of stars
- GALEX – (telescope) Galaxy Evolution Explorer, an ultraviolet space telescope
- GASP – (software) Guide star Astrometric Support Package
- GAT – (catalog) AO (Gatewood+), catalog of G. Gatewood's observations
- GBT – (telescope) Green Bank Telescope
- GC – (catalog) General Catalog, a catalog of clusters, nebulae, and galaxies created by John Herschel and now superseded by the New General Catalogue
- GCAS – (celestial object) Gamma CASsiopeiae, a class of eruptive variable stars named after Gamma Cassiopeiae, the archetype for the class
- GCMS – (instrumentation) – Gas Chromatograph and Mass Spectrometer, an instrument on the Huygens probe
- also GC/MS
- GCN – (organization) GRB Coordinates Network
- GCR – (astrophysics terminology) Galactic Cosmic Rays
- GCVS – (catalog) the General Catalog of Variable Stars
- GD – (catalog) Giclas Dwarf, a catalog of white dwarf
- GDS – (celestial object) Great Dark Spot, a transient feature in the clouds of Neptune
- GEM – (observing program) Galactic Emission Mapping
- GEM – (observing program) Galileo Europa Mission, the science observation program of Europa performed by the Galileo spacecraft
- GEM – (observing program) Giotto Extended Mission, the extended operations of the Giotto spacecraft
- GEMS – (organization) Group Evolution Multi-wavelength Study
- GEMS – (survey) Galaxy Evolution from Morphology and Spectral energy distributions
- GEMSS – (organization) Global Exoplanet M-dwarf Search-Survey, a search for exoplanets around m-dwarf stars
- GEODDS – (telescope) Ground-based Electro-Optical Deep Space Surveillance, a network of telescopes used in a United States Air Force program for observing space junk
- GEOS – (organization) Groupe Européen Observations Stellaires, an amateur and professional association for study of variable stars.
- GERLUMPH – (instrumentation) GPU-Enabled, High Resolution MicroLensing Parameter survey, where GPU is an acronym for Graphics Processing Unit.
- GH – (catalog) Giclas Hyades, a catalog of stars in the Hyades cluster
- GHRS – (instrumentation) Goddard High Resolution Spectrograph, a spectrograph on the Hubble Space Telescope
- also HRS
- GIA – (organization) Gruppo Italiano Astrometristi
- GIMI – (instrumentation) Global Imaging Monitor of the Ionosphere, an ultraviolet imager on the Advanced Research and Global Observation Satellite
- GJ – (catalog) Gliese & Jahreiß/Jahreiss nearby star catalog
- GL – (catalog) Gliese nearby star catalog
- GLAST – (telescope) Gamma-ray Large Area Space Telescope
- GLIMPSE – (observing program) Galactic Legacy Infrared Mid-Plane Survey Extraordinaire
- GMC – (celestial object) Giant molecular Cloud
- GMF – (celestial object) Galactic Magnetic Field
- GMRT – (telescope) Giant Meter Radio Telescope
- GMT – (telescope) – Giant Magellan Telescope, a telescope being built by a US-Australian collaboration
- GONG – (organization) Global Oscillation Network Group, an organization that monitors oscillations in the Sun
- GOODS – (survey) Great Observatories Origins Deep Survey a survey of various redshifts to study galactic formation and evolution
- GP – (astrophysics terminology) Giant Pulses, a type of observed pulse emission from pulsars
- GPS – (astrophysics teminology) GHz-Peaked Spectrum, the radio or microwave spectra of some galaxies
- GR – (astrophysics terminology) General Relativity
- GR – (catalog) Giclas Red dwarf, a catalog of red dwarfs
- GRB – (celestial object) Gamma Ray Burst
- GRO – (telescope) Gamma Ray Observatory, another name for the Compton Gamma Ray Observatory
- GROSCE – (telescope) Gamma Ray Burst Optical Counterparts Search Experiment, an automated telescope used to detect the optical counterparts to gamma ray bursts
- GRS – (instrumentation) Gamma Ray Spectrometer, an instrument on the Mars Observer
- GRS – (celestial object) Great Red Spot, a feature in the clouds of Jupiter
- GSC – (catalog) Guide Star Catalog, a catalog of stars used for pointing the Hubble Space Telescope
- GSC2 – (catalog) Guide Star Catalog version 2, a catalog of stars used for pointing the Hubble Space Telescope
- also GSC II
- GSFC – (organization) Goddard Space Flight Center, a NASA institution
- GSPC – (catalog) Guide Star Photometric Catalog, a catalog of stars with precisely measured fluxes used to calibrate the Guide Star Catalog
- GTC – (telescope) Gran Telescopio Canarias, the 10.4 m reflecting telescope on the island of La Palma, Canary Islands, Spain
Read more about this topic: List Of Astronomy Acronyms