SIZE IN SPACE

dwarf planet · Object guide

How big is Pluto?

A small world, not a small idea.

One scale. Two worlds.True diameter scale
Pluto and Earth to scaleTheir diameters differ by a factor of 5.3614. Illustrations show body diameter, not separation in space.

Body diameters to scale. Positions and surface artwork are illustrative; Saturn’s rings are excluded.

A change of perspective

5.3614× the diameter. See how the two worlds measure up.

Diameter is a distance across an object. Volume grows with the cube of that distance.

Choose a size to bring this comparison down to Earth.

Pluto: Twice the source mean radius; body diameter only, excluding rings.

Earth: Twice the source mean radius; body diameter only, excluding rings.

How we measure size →
Mean diameter

2,376.6 km

Twice the source mean radius; body diameter only, excluding rings.

Pluto and the Moon offer an approachable comparison: both remain easy to see on the same screen. Try predicting which disk will be wider before checking the labels.

A different way to explore

Compare Pluto with Earth, then move directly to Jupiter. You do not need to follow a fixed sequence. The object selectors let your own questions determine the next step.

Measurement source

Planetary Physical Parameters — NASA JPL. Twice the source mean radius; body diameter only, excluding rings.

Source references