Io
moon of Jupiter
5.37 AU from Earth
The most volcanic world known. Tidal squeezing by Jupiter melts its interior, feeding hundreds of volcanoes and lava lakes.
- radius 1,822 km · 400 active volcanoes
- plumes of sulphur rise 400 km into space
Numbers that change with time are from 8 November 2026.
open Io in the atlas ›- kind
- place in the Solar System · moon or small world
- distance
- 421,700 km from Jupiter
- size
- 3,640 km across
- orbits
- Jupiter