Uranus · natural satellite

Portia

Mean diameter: Not available
Mean orbital distance: 66,101 km from centre
Orbital period: 0.513 Earth days

Orbit & discovery

Surface gravity: Not available
Discovery: 1986
Discoverer / team: Voyager Science Team
Provisional designation: S/1986 U1
JPL satellite ID: 712
Orbital eccentricity: 0.004
Inclination: 2.7 degrees

Inclination reference: Laplace. Mean-element epoch: 2025-01-01.0 TDB · URA184.

Diameters use volume-equivalent mean radii, including for irregular bodies. Mean orbital elements describe an orbit; they are not live positions. Missing physical measurements remain unavailable.

Missions in the Uranus system · 1 records

1 launches · 0 linked events

These records cover the planetary system. A system mission did not necessarily visit this moon. Dedicated targets are marked separately; programme events include the journey and briefings. Launch outcomes do not establish arrival, landing success or present spacecraft operation.

Dedicated targets only

PLANETARY SYSTEM

Voyager 2

August 20, 1977 · UTC

Lockheed Martin · Titan IIIE

1 records from the complete 9,386‑record production catalogue.

Sources & measurements