Mustafar is a fictional exoplanet in the Star Wars universe. It is depicted in Star Wars Episode III: Revenge of the Sith.
The planet is covered by hundreds of caldera, most of which are in a state of constant eruption. The volcanic activity is caused by gravitational stresses on the planet created by the two gas giants that affect its orbit (similar to Jupiter's Galilean moons). An automated energy and mineral collection facility on the planet is used by the Separatist Council as their last headquarters.
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