Aster › Space program › Iapetus
Iapetus
Position on the route: 20/45 · level needed 130 · journey (Mk0 engine) 24.6 h
By the numbers
| Diameter | 1,469 km |
|---|---|
| Gravity | 0.223 m/s² |
| Orbit | 79 days |
| Feature | two-tone face, equatorial ridge |
The story
One half is as dark as coal, the other as bright as snow. The dark material is explained by dust from neighbouring moons; the dark side heats in the sun and moves ice to the other side, widening the contrast.
A ridge 20 km high and 1,300 km long runs along its equator, the reason for its ‘walnut’ look. Cassini found it in 2004.
Missions
- Cassini (2004, 2007): a close flyby and the discovery of the ridge
Colony note
Distant and quiet, with low radiation. The dark face is good ground for solar panels.
What probes bring back
- One face dark, the other bright: the dark material is explained by dust from Phoebe.
- A ridge 20 km high runs along the equator.