Io's break to escape Jupiter

Nature: Jupiter's moon Io is about the same size as our Moon, but the similarities end there.

Its motion around Jupiter is tightly constrained by its gravitational interactions with the giant planet and with two of Jupiter's other moons, Europa and Ganymede.

Io's orbital imprisonment is the cause of its spectacular volcanism. But Valéry Lainey, Jean-Eudes Arlot, Özgür Karatekin, and Tim Van Hoolst have provided evidence that Io is loosening the bonds that hold it in its unexpectedly elliptical path around Jupiter. If it eventually breaks free, the most volcanically active object in our Solar System will become dormant.

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