The mean diameter of Ganymede is about 1.09 times the mean diameter of Callisto. Selected basis: approximate values.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions.
4,821 km - Mean diameter; approximate.
Callisto is a natural satellite of Jupiter, with a heavily cratered icy surface.
Rounded mean-radius model of Callisto. The derived area and volume describe a sphere; surface terrain and flattening are omitted.
NASA JPL — Planetary satellite physical parameters5,262 km - Mean diameter; approximate.
Ganymede is a natural satellite of Jupiter and contains a magnetic field generated by its partially liquid core.
Rounded mean-radius model of Ganymede. The derived area and volume describe a sphere; surface terrain and flattening are omitted.
NASA JPL — Planetary satellite physical parameters
There’s always another scale
SpaceCallisto4,821 kmCallisto is a natural satellite of Jupiter, with a heavily cratered icy surface.
SpaceGanymede5,262 kmGanymede is a natural satellite of Jupiter and contains a magnetic field generated by its partially liquid core.
SpaceMoon3,475 kmThe Moon is Earth’s natural satellite and the brightest large object in Earth’s night sky.
SpaceEarth12,740 kmEarth is the rocky planet on which we live and the third planet from the Sun.
SpacePluto2,377 kmPluto is a dwarf planet in the Kuiper Belt, composed of rock and ice and orbiting the Sun.
SpaceJupiter139,800 kmJupiter is a giant planet composed mainly of hydrogen and helium, orbiting the Sun beyond the asteroid belt.Side by side
Illustrative artwork · not to scale
Illustrative artwork · not to scale
Illustrative artwork · not to scale
Illustrative artwork · not to scaleGot a good eye for scale?