archive / atlas record
Ganymede
The largest moon and the only one known with an intrinsic magnetic field.
- classification
- Icy moon
- system
- Jupiter system
Ganymede is larger than Mercury and contains a differentiated interior, an icy shell and evidence for a buried ocean.
- Class
- Icy moon
- Location / system
- Jupiter system
- Distance
- 1.07 million km mean distance from Jupiter
Only values with an established scientific consensus are listed. Where a quantity is uncertain or model-dependent, it is discussed in the sections below rather than stated as data.
Overview (starter entry, expanded review pending)
Ganymede is larger than Mercury and contains a differentiated interior, an icy shell and evidence for a buried ocean.
Imaging, spectra and orbital dynamics
Ganymede's surface or atmosphere is constrained by telescopic and spacecraft imaging where available; spectra identify materials, while repeated position measurements establish its orbit and system context.
- What remains least constrained about Ganymede?Composition, internal structure, formation history or local environment can require different observations and may remain model-dependent.
Items above are unresolved. Hypotheses are labelled as such and are not presented as confirmed findings.
NASA // verified 28 September 2026
NASA/JPL // verified 28 September 2026