Io - NASA Science

Facts About Io

Jupiter's moon Io is the most volcanically active world in the solar system, with hundreds of volcanoes, some erupting lava fountains dozens of miles (or kilometers) high.

Io is caught in a tug-of-war between Jupiter's massive gravity and the smaller but precisely timed pulls from two neighboring moons that orbit farther from Jupiter—Europa and Ganymede. Io’s volcanoes are at times so powerful that they are seen with large telescopes on Earth, and Io even has lakes of molten silicate lava on its surface. Only slightly larger than Earth’s Moon, Io is about one-quarter the diameter of Earth itself.

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NASA Juno Mission Spots Most Powerful Volcanic Activity on Io to Date

Even by the standards of Io, the most volcanic celestial body in the solar system, recent events observed on the…

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NASA Photojournal: Io

Images of Io gathered by NASA spacecraft.