Moon of Saturn
Enceladus
An icy moon spraying its ocean into space.
Enceladus orbits Saturn every 32.9 hours and is locked in a 2:1 resonance with Dione, completing two orbits for each of Dione's one. Dione's pull keeps Enceladus on a slightly elliptical path, so Saturn's tides flex it. That flexing helps power the jets of water that spray from its south pole.
How it moves
- Enceladus orbits Saturn every 1.370 days (32.9 hours) at about 238,020 km.
- It orbits twice for every single orbit of Dione (a 2:1 resonance).
- Dione's gravity stretches Enceladus's orbit into a slight ellipse, driving tidal flexing.
- It is tidally locked and travels inside the densest part of Saturn's E ring.
- Material from its jets spreads along its orbit and supplies the E ring.
Facts
- Mean radius
- 252.1 km
- Mass
- 1.080e+20 kg
- Surface gravity
- 0.113 m/s²
- Rotation period
- 32.885 hours
- Orbital period
- 1.37 days
- Average orbital distance
- 238,020 km
- Eccentricity
- 0.0045
- Discovered
- August 28, 1789, by William Herschel
Enceladus feeds one of Saturn's rings: its icy spray spreads along its orbit to form the E ring.
Sources: nssdc.gsfc.nasa.gov, ssd.jpl.nasa.gov, ssd.jpl.nasa.gov