Jupiter's Largest Moon Has a Rare Magnetic Field. A Strange Theory May Explain It
gizmodo.com
Ganymede shouldn't still have a magnetic field — but a bold new theory about its churning interior forces us to rethink everything we know about planetary dynamo theory.
Dynamo TheoryPlanetary DifferentiationTidal HeatingMagnetohydrodynamics
Theory Briefing
- Ganymede is the solar system's largest moon and uniquely possesses its own magnetic field, a phenomenon scientists struggle to explain.
- A new study proposes Ganymede's core is still hot and churning, generating a dynamo effect long after it should have cooled down.
- The finding challenges standard planetary cooling models, suggesting internal heat sources or tidal forces may sustain magnetic fields far longer than theory predicts.