Cryovolcanism also occurs in the Neptune system. Triton,
Neptune’s largest moon, is an irregular moon. In one
proposed scenario, Triton was migrating along with a similarly
sized close companion; Triton was captured, and the
companion carried away the excess angular momentum. To
achieve its present circular, synchronous orbit, Triton must
have experienced extreme tidal stresses from Neptune following
its capture. As on Io, such stresses would have gen-erated large amounts of thermal energy. The interior might
even have melted, allowing Triton to become chemically
differentiated.