HOW BIG
DiscoverMoons

Moons

Io: size, dimension and comparison

The adopted reference is about 3,643 km.

Mean diameter ≈ 3 643 km

3,643 km ≈ 3,643,000 m. A kilometer contains 1,000 meters.

A natural satellite of Jupiter.

Explore at this scale
Io, interpreted illustration
Interpreted illustration · dimension stated in the fact sheet.

What does this number measure?

Size calculated from the mean radius published by NASA/JPL: the diameter of a sphere with equivalent volume. The actual shape of small moons can be highly irregular.

Compare the stated dimensions

The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.

Compare with Moon in the explorer →

Source and limitations

Catalogue value: a source is provided, but the measurement has not been individually audited in this project.

Uncertainty stated in the catalogue: about 1 km.

Interpreted astronomical view. The textures are illustrative; this image is neither a space mission photograph nor a scientific map.