Moons of the Solar System
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Another of Jupiter's moons is Io, which may be the most colorful moon in the solar system. Io is certainly the most volcanically active moon, even more so than the planet Earth. This picture shows a volcano erupting, throwing solid materials 100 miles high.
Fun Fact: Molten rock is constantly re-forming the surface of Io. In fact, scientists observed one volcano move 50 miles across the surface of Io in the span of just 17 years.
Photo source: NASA