Exploratour - Volcanoes of the Solar System
The diagram to the left shows the interior of Io, based on recent measurements by the Galileo spacecraft. It shows a large iron/sulphur core (the Earth's core is iron/nickel), overlain with a silicate rocky material.
As shown in the figure, possible pools of melted, liquid sulphur, encounter hot pockets of Io's interior and boil, providing Io with geysers on the surface.
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