Saturn · natural satellite

Rhea

Cratered icy plains

Saturn’s second-largest moon has a heavily cratered surface. Cassini observed its bright icy terrain and faint atmosphere.

Mean diameter: 1,527 km
Mean orbital distance: 527,200 km from centre
Orbital period: 4.518 Earth days

Rhea · NASA spacecraft imagery — NASA/JPL/Space Science Institute · Image source ↗

Compared with our Moon

Rhea · 1,527 km

Moon · 3,474.8 km

One diameter scale. Circle shapes compare volume-equivalent diameters; irregular moons are not spheres.

Orbit & discovery

Surface gravity: 0.264 m/s²
Discovery: 1672
Discoverer / team: G.D. Cassini
Provisional designation: —
JPL satellite ID: 605
Orbital eccentricity: 0.001
Inclination: 0.3 degrees

Inclination reference: Laplace. Mean-element epoch: 2000-01-01.5 TDB · SAT441.

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.

Physical measurements & uncertainties

Mean radius · km: 763.50 ±0.60 [1]
GM · km³/s²: 153.94175 ±0.00041 [SAT441]
Density · g/cm³: 1.2372 ±0.0029 [*]

Missions in the Saturn system · 5 records

5 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 · UPCOMING