Moon

Io

The most volcanic body in the Solar System.

Hundreds of active volcanoes spew sulfur and silicate lava up to 500 km high, driven by Jupiter's tidal forces.

See also

Ganymede

Largest moon in the Solar System.

The Moon

Earth's constant companion.

Europa

Jupiter's ice world with a hidden ocean.

Titan

Saturn's moon with rivers of liquid methane.

Phobos

Mars' larger, doomed inner moon.

Deimos

Mars' tiny outer moon.