Cosmic Scale
Dione
Moon of Saturn · 377,396 km from Saturn
How big is Dione?
Dione is about 1,123 km across.
See Dione in 3D, at true scale
Dione is an icy moon of Saturn with bright ice cliffs streaking its trailing side. Cassini found hints of a buried ocean beneath its crust.
At a glance
| Diameter | 1,123 km |
|---|---|
| Mass | 1.09 × 10²¹ kg |
| Diameter compared with Earth | 0.088 × Earth |
| Size | 1,123 km |
| Orbits | Saturn, every 2.7 days |
| Discovered | 1684, Giovanni Cassini |
| Visited | Cassini, 2004–2017 |
Good to know
- The bright streaks once thought to be frost turned out to be ice cliffs hundreds of metres high.
- It has a very thin atmosphere of oxygen ions.
- Two small moons share its orbit, ahead of and behind it.