Callisto

Callisto is Jupiter's second-largest moon and a heavily cratered world.[3]

History

Galileo Galilei discovered Callisto in 1610.[3]

Findings

The Galileo orbiter later carried out the first detailed survey of Jupiter and its large moons.[3] Galileo data indicated that a salty ocean may lie beneath Callisto's surface.[3] JPL lists Callisto's mean radius as 2,410.3 kilometres.[1]

Current status

NASA notes that the possible ocean made Callisto a candidate world in the search for life.[3] The USGS maintains a mapped catalogue of named Callisto features.[2]

Sources

  1. Solar System Dynamics: Physical Parameters. Licence: facts-only (Track B), no text reused. Attribution: NASA/JPL-Caltech.
  2. Gazetteer of Planetary Nomenclature. Licence: US federal work, public domain (17 USC 105). Attribution: U.S. Geological Survey.
  3. Callisto | NASA Science. Licence: facts-only (Track B), no text or images reused. Attribution: NASA.

Evidence as of 2026-11-01.