Astronomy
Articles about stars, planets, space and the universe.
George's Secret Key to the Universe
Geostationary orbit
Geosynchronous orbit
Gertrude (crater)
Giant impact hypothesis
Giant impact hypothesis: origin of the Moon
Giant Magellan Telescope
Giant star
Gihō calendar
Ginga (satellite)
Ginga (Astro‑C): Japanese X‑ray Astronomy Satellite
Gliese 581
Gliese 581 c
Gliese 667 Cc
Gliese 667 Cc — potentially habitable super-Earth in the Gliese 667 system
Gliese 876
Gliese 876 — nearby red dwarf with a resonant multiplanet system
Globular cluster
GN-z11
GN-z11 — an early, distant galaxy
Gould Belt
Gravitational lensing
Gravity assist
GRB 970228
GRB 970228 — first gamma‑ray burst with a detected afterglow
Great Attractor
Great Attractor: a nearby gravitational concentration in the local universe
Great Comet of 1811
Great Comet of 1811 (C/1811 F1)
Great Dark Spot
Great Observatories program
Great Red Spot
Great Red Spot (Jupiter's long‑lived storm)
Great Wall
Great White Spot
Great White Spot (Saturn): periodic planet‑encircling storms
Greip (moon)
Greip (Saturn moon)
Grus (constellation)
H I region
H I region (neutral atomic hydrogen cloud)
H II region
Habitable zone
Habitable zone (Goldilocks zone)
Halimede (moon)
Halley's Comet
Harpalyke (moon)
Hati (moon)
Hati (moon) — Saturn XLIII, a small retrograde irregular satellite
Haumea (dwarf planet)
Hayabusa
Hayabusa (Japanese asteroid sample-return spacecraft)
Hegemone (moon)
Hegemone (Jupiter XXXIX): an irregular retrograde moon of Jupiter
Helene (moon)
Helene (moon of Saturn)
Helike (moon)
Heliocentrism
Heliocentrism: The Sun-centered model of the Solar System
Heliocentrism is the model that places the Sun near the center of the Solar System. This article outlines its principles, historical development, evidence, and how it differs from
Heliosphere
Helix nebula
Helix Nebula (NGC 7293): a nearby planetary nebula in Aquarius
Hercules–Corona Borealis Great Wall
Hermippe (moon)
Hermippe: Jupiter's irregular moon (Jupiter XXX)
Herschel Space Observatory
Herschel Space Observatory: ESA's Far-Infrared and Submillimetre Telescope
Herse (moon)
Herse (moon of Jupiter)
Hertzsprung–Russell diagram
Hertzsprung–Russell diagram (H-R diagram)