Io

Io is a Jovian moon marked by intense volcanic activity.[1] According to JPL, Io measures 1,821.49 kilometres in mean radius.[2] Io belongs to the group of four large moons called the Galilean moons.[3]

History

During a 1979 flyby, Voyager 1 saw evidence that Io was volcanically active.[1]

Findings

Hundreds of volcanoes are active on Io.[1] Some eruptions send lava fountains high above the surface of Io.[1] Gravity from Jupiter and timed pulls from Europa and Ganymede deform Io.[1]

Sources

  1. Io | NASA Science. Licence: facts-only (Track B), no text or images reused. Attribution: NASA.
  2. Physical Parameters of Natural Satellites | NASA/JPL. Licence: facts-only (Track B), no text reused. Attribution: NASA/JPL-Caltech.
  3. Facts about Jupiter | European Space Agency. Licence: facts-only (Track B), no text reused. Attribution: European Space Agency.

Evidence as of 2026-11-01.