Io is the most volcanically active moon in our solar system, orbiting the planet Jupiter. It hosts over 400 active volcanoes, with lava fountains that can reach dozens of miles into space. The surface features vast lakes of molten silicate lava, such as Loki Patera, which spans more than 200 kilometers in diameter. Io’s surface displays vibrant colors like yellow and orange, caused by sulfur and other volcanic chemicals continuously replenished through frequent eruptions.

The primary source of heat on Io is tidal heating. Its elliptical orbit between Jupiter and other moons creates gravitational friction within its rocky layers, generating enough heat to melt rock into magma. Discovered by Galileo Galilei in 1610, Io remains geologically young. Its intense volcanism constantly resurfaces the moon, leaving few visible impact craters.

Io’s active geology, driven by tidal forces, makes it a key subject for understanding planetary dynamics and internal heating processes.