Every world / Moon of Jupiter

Io

Outline The numbers here are measured. The rest of this page is being written.

The path of Io round Jupiter, seen from above and drawn to scale, with the white dot at its nearest point. Orbit from NASA/JPL Solar System Dynamics, planetary satellites.

Kind: Moon of Jupiter
Distance: 421,800 km from Jupiter on average
Once round: 42.5 hours
Path: very nearly a circle (eccentricity 0.004), tilted 0°
Size: 3,643 km across, 105 per cent of our Moon’s width
Density: 3.53 times water
Found: 1610, by Galileo

Jupiter On the atlas In 3D

Io, our Moon and Jupiter, drawn to one scale from their measured sizes, as plain discs.

Still being written

What it looks like up close
What it is made of
How it was found
Spacecraft that have seen it
What is still unknown

Sources: NASA/JPL Solar System Dynamics, planetary satellites.