Adjective(s) Unknown
Orbital properties
Aphelion/apoapsis 1897000 km
Perihelion/periapsis 1869000 km
Semi-major axis 1 882 700 km
Orbital eccentricity 0.0074
Orbital period 16.6890184 d
Average orbital speed 8.204 km/s
Physical properties
Radius 2410.3±1.5 km (0.378 Earths)
Mass (1.075938±0.000137)×1023 kg
(0.018 Earths)
Mean density 1.8344±0.0034 g/cm3
Escape velocity 2.440 km/s
Rotation period synchronous
Average surface temperature min mean max

80±5 134±11 165±5

Apparent magnitude 5.65 (opposition)
Moons 0

Callisto is the third largest moon in the Solar System. It orbits around the planet Jupiter.


  • Galileo discovered Callisto, along with Io, Ganymede, and Europa, in 1610.
  • Like the rest of the Galilean Satellites, Callisto is named after one of Zeus's lovers.