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Astronomy

The Orbital Resonances of Jupiter's Galilean Moons

Quick fact

Io, Europa, and Ganymede are in a 1:2:4 resonance, meaning for every one orbit Io completes, Europa completes two, and Ganymede completes exactly four. This resonance is so precise that it has remained stable for billions of years.

Why this is interesting

Jupiter's largest moons are not just subjects of gravity; they are locked in a delicate gravitational dance that makes one of them the most volcanically active world in the solar system and another a prime candidate for hosting life. How can a simple orbital pattern create such extremes?