HOW BIG
DiscoverMoons

Moons

Hydra: size, dimension and comparison

The adopted reference is about 37 km.

Mean diameter ≈ 37 km

37 km = 37,000 m. A kilometer contains 1,000 meters.

A natural satellite of Pluto.

Explore at this scale
Hydra, 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 Helene 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 2 km.

Silhouette inspired by New Horizons; fine terrain details are hypothetical. Volume-equivalent diameter, not maximum length.