Quick Facts

  • Age:

  • Diameter: ~

  • Adjective used: Callistoan, Callistan, Callistian, Callistonian

  • Pronunciation:

  • Alternate names: Jupiter IV

  • Callistian Day:

  • Callistian Year:

  • Type: Tidally-locked natural satellite

  • Distance from Jupiter: ~ 1,880,000 KM

  • Natural Satellite: 0

Callisto, also known as Jupiter IV, is the second-largest moon of the Jupiter. It is the third largest natural satellite in the solar system after Ganymede and Saturn’s Titan. Callisto is tidally locked with the Jupiter, hence the same hemisphere of Callisto faces the Jupiter always. Callisto possess an icy surface which is heavily saturated with craters.

Named after

Callisto is named after one of the lovers of Zeus, the Greek mythological god of sky and thunder, and counterpart of Roman king Jupiter. Callisto is named after Kallisto, a nymph who attracted Zeus.

Discovered by

Callisto was discovered Jan. 7, 1610, by Italian scientist Galileo Galilei along with Jupiter’s three other largest moons: Io, Euorpa, Ganymede.