Io

The world of volcanoes

The Galilean moon famous for its intense volcanic activity.

Educational illustration · shapes and sizes are not to scale.

Orbiting: Jupiter
Category: Natural satellite

What makes this world interesting

Gravitational interactions in the Jovian system maintain strong internal heating.

Observe or explore it

Locate Io as a point near Jupiter; its volcanoes are not visible in a small telescope.

Connect the discoveries

Jupiter

Sources and reference information

NASA Science — Io

Rounded educational data, sources consulted on 18 October 2026. Orbital distances are mean reference distances from the Sun, not current distances from Earth. Periods are expressed in Earth time. The planner provides date-specific positions for supported targets.