Andromeda
Log inJoin

Moon of Neptune

Thalassa

Open in OuranosCompare its size

A moon of Neptune.

At Neptune.

Measured

Mean radius
40 km
Goes round once every
7.48 hours
Distance from Neptune
about 50,100 km (its orbit's average)
Orbit
inclined 0.2°, eccentricity 0.001
JPL / NAIF id
804

How far, from the Earth

About 29.3 AU. To cross it:

  • Light4 hours 3 minutes
  • Voyager 1's speed8.22 years
  • Driving at 100 km/h4,990 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.