# Callisto

*In the Solar System*

The outermost of Jupiter's four large moons and the most heavily cratered surface in the Solar System: an old, dark, frozen face that has hardly changed in four billion years. It stays outside the orbital resonance that heats its neighbours, so it was never kneaded from inside, and it seems only partly separated into rock and ice. Even so, the way it disturbs Jupiter's magnetic field suggests a thin ocean far down.

| | |
| --- | --- |
| Radius | 2,410 km |
| Around the equator | 15,144 km |
| From the Sun | 794,683,946 km (+706,252 km/d) |
| From the Earth | 869,283,021 km (-1,253,405 km/d) |
| A signal takes | 48 min |
| Goes round | Jupiter |
| Placed to within | 482 km |

Distances and speed are computed from JPL Horizons trajectories and are true of 2026-10-09, changing at the rate given beside each. The interpolation itself is good to a few kilometres; what ages these figures is the date, not the arithmetic.

## Elsewhere

- On the live map: https://www.orbitalmap.space/?world=solar-system&focus=callisto
- This object as a page: https://www.orbitalmap.space/o/callisto/
- Every object: https://www.orbitalmap.space/o/
- What this site is and what it reads: https://www.orbitalmap.space/llms.txt