Io
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One of Jupiter's moons. Io is the only
celestial body, other than Earth, that
is known to have active volcanoes.
When Io was first colonized, a high
concentration of minerals and ores
was discovered. Today, Io boasts the
largest off-Earth mining operation.
Although Io's volcanoes are rich with
raw materials, for safety reasons,
most mines are located away from the
volcanoes.