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Featured planetary moon

Triton

A captured world moving backward around Neptune.

Triton follows a retrograde orbit, strong evidence that it formed elsewhere and was captured by Neptune. Its young icy surface, thin atmosphere and active plumes make it one of the most distinctive outer-system worlds.

Orbit representation
Representative mean elements
Surface
derived map

Reference measurements

The numbers that shape this world

Mean radius
1,352.6 km
Mean orbital distance
354,800 kmSemi-major axis around the parent body.
Orbital period
5.877 days
Eccentricity
0
Inclination
157.3°Local Laplace plane from the JPL pole
Rotation
Tidally locked

World portrait

Capture rewrote an entire system

Triton’s arrival likely disturbed Neptune’s earlier satellite family. Its orbital direction is therefore not a minor parameter but the key to the moon’s origin story.

System geometry

Triton in motion around Neptune

Triton travels at a mean orbital distance of 354,800 km and completes a circuit in 5.877 days. Its eccentricity of 0 and 157.3° inclination are read against Local Laplace plane from the JPL pole. Synchronous rotation keeps the same hemisphere broadly oriented toward the parent body.

Representation notes

What Explore is showing

JPL fitted mean elements describe general orbit shape and orientation; they are not an accurate ephemeris.

Reviewed official partial imagery prepared as a 1K display texture. Unobserved areas are softly completed from the observed hemisphere so the globe remains natural-looking in motion; the body summary identifies those regions as reconstructed rather than directly observed. Final seam, pole and landmark review remains device-dependent.

Provenance

Sources and related destinations