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3.1.4 The Io question answered

Figure 10 Io image captured by Galileo in 1997.

Answer – thanks to orbital resonance with Europa, the varying tidal forces on Io caused by the eccentricity of its orbit around Jupiter are so strong that Io’s tidal bulges rise and fall by up to 100 m during a single orbit, and also migrate to and fro a little. This distortion generates an immense amount of heat, fuelling the most volcanic body in the Solar System.


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