Moon of Jupiter
Callisto
Jupiter's outermost large moon, cratered and calm.
Callisto orbits Jupiter every 16.7 days, well outside the resonance that binds Io, Europa, and Ganymede. With little tidal heating, its ancient surface is covered in craters. It keeps one face toward Jupiter as it goes.
How it moves
- Callisto orbits Jupiter every 16.689 days at about 1,882,700 km.
- It sits outside the 1:2:4 resonance of the three inner Galilean moons.
- Callisto is tidally locked, with the same hemisphere always facing Jupiter.
- It is the third largest moon in the solar system.
Facts
- Mean radius
- 2,410.3 km
- Mass
- 1.076e+23 kg
- Surface gravity
- 1.24 m/s²
- Rotation period
- 400.536 hours
- Orbital period
- 16.689 days
- Average orbital distance
- 1,882,700 km
- Eccentricity
- 0.007
- Discovered
- January 7, 1610, by Galileo Galilei
Galileo spacecraft data suggest Callisto may hide a salty ocean beneath its battered surface.
Sources: nssdc.gsfc.nasa.gov, ssd.jpl.nasa.gov, ssd.jpl.nasa.gov