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Moon of Pluto

Hydra

Open in OuranosCompare its size

A moon of Pluto.

At Pluto.

Measured

Mean radius
18.5 km
Goes round once every
38.2 days
Distance from Pluto
about 65,200 km (its orbit's average)
Orbit
inclined 0.3°, eccentricity 0.009
JPL / NAIF id
903

How far, from the Earth

About 36 AU. To cross it:

  • Light4 hours 59 minutes
  • Voyager 1's speed10.1 years
  • Driving at 100 km/h6,140 years

Voyager 1 at the speed it moved outward over the year to 2026-10-25 (JPL Horizons). Driving: nonstop, never refuelling.

Where this comes from

  • Moons: JPL Planetary Satellite Mean Elements and Physical Parameters, paced to JPL Horizons. NASA/JPL-Caltech. Sizes JPL leaves out are estimates, mostly from brightness: Scott Sheppard's moon pages at Carnegie.

Every catalogue Ouranos draws is credited on the credits page.