Jupiter · natural satellite
Ganymede
The largest moon
Ganymede is larger in diameter than Mercury. It has its own magnetic field, bright grooved terrain and older dark regions. It is Juice’s main target.
- Mean diameter
- 5,262.4 km
- Mean orbital distance
- 1,070,400 km from centre
- Orbital period
- 7.156 Earth days
Compared with our Moon
One diameter scale. Circle shapes compare volume-equivalent diameters; irregular moons are not spheres.
Orbit & discovery
- Surface gravity
- 1.428 m/s²
- Discovery
- 1610
- Discoverer / team
- Galileo
- Provisional designation
- —
- JPL satellite ID
- 503
- Orbital eccentricity
- 0.001
- Inclination
- 0.2 degrees
Inclination reference: Laplace. Mean-element epoch: 2000-01-01.5 TDB · JUP365.
Diameters use volume-equivalent mean radii, including for irregular bodies. Mean orbital elements describe an orbit; they are not live positions. Missing physical measurements remain unavailable.
Physical measurements & uncertainties
- Mean radius · km
- 2631.20 ±1.70 [1]
- GM · km³/s²
- 9887.83275 ±0.00247 [JUP365]
- Density · g/cm³
- 1.9416 ±0.0038 [*]
Missions in the Jupiter system · 24 records
9 launches · 15 linked events
These records cover the planetary system. A system mission did not necessarily visit this moon. Dedicated targets are marked separately; programme events include the journey and briefings. Launch outcomes do not establish arrival, landing success or present spacecraft operation.
Juice Ganymede Impact
Date to be confirmed
European Space Agency
Juice Ganymede Orbit Insertion
December 2034 · date to be confirmed
European Space Agency
Juice Jupiter Orbit Insertion
July 2031 · date to be confirmed
European Space Agency
Juice Earth Flyby
January 2029 · date to be confirmed
European Space Agency
Europa Clipper Earth Flyby
December 2026 · date to be confirmed
Jet Propulsion Laboratory
Juice Earth Flyby
September 28, 2026 · UTC
European Space Agency
Juice Venus Flyby
August 31, 2025 · UTC
European Space Agency
Europa Clipper Mars Flyby
March 1, 2025 · UTC
Jet Propulsion Laboratory
Europa Clipper
October 14, 2024 · UTC
SpaceX · Falcon Heavy
Europa Clipper News Conference
September 17, 2024 · UTC
Jet Propulsion Laboratory
Europa Clipper Update Briefing
September 9, 2024 · UTC
Jet Propulsion Laboratory
Juice Moon-Earth Flyby
August 19, 2024 · UTC
European Space Agency
Europa Clipper One Year From Launch Public Talk
October 20, 2023 · UTC
National Aeronautics and Space Administration
JUICE (JUpiter ICy moons Explorer)
April 14, 2023 · UTC
Arianespace · Ariane 5 ECA+
ESA JUICE Pre-Launch Press Briefing
April 6, 2023 · UTC
Juno Europa Flyby
September 29, 2022 · UTC
Juno's New Findings Press Conference
October 28, 2021 · UTC
Juno
August 5, 2011 · UTC
United Launch Alliance · Atlas V 551
New Horizons
January 19, 2006 · UTC
United Launch Alliance · Atlas V 551
STS-34 (Galileo)
October 18, 1989 · UTC
Lockheed Space Operations Company · Space Shuttle
Voyager 1
September 5, 1977 · UTC
Lockheed Martin · Titan IIIE
Voyager 2
August 20, 1977 · UTC
Lockheed Martin · Titan IIIE
Pioneer 11
April 6, 1973 · UTC
United States Air Force · Atlas SLV-3D Centaur
Pioneer 10
March 3, 1972 · UTC
United States Air Force · Atlas SLV-3C Centaur
No dedicated-target flight is recorded for this moon.
24 records from the complete 9,386‑record production catalogue.
Sources & measurements
- JPL · IAU-recognized satellite discoveries ↗
- JPL · physical parameters and uncertainties ↗
- JPL · mean orbital elements ↗
- NASA NSSDCA · Jovian sidereal orbital periods ↗
- NASA · planetary exploration history ↗
- NASA · Voyager encounters ↗
- NASA · Galileo ↗
- NASA · Juno ↗
- NASA · Cassini–Huygens ↗
- NASA · New Horizons ↗
- ESA · Juice targets ↗
- NASA · Europa Clipper ↗
- NASA · Dragonfly ↗
- JAXA · MMX ↗