Reference image
Object guide
Callisto's surface is one of the most heavily cratered in the Solar System and preserves a record of early bombardment. It may host a subsurface ocean, but it is less geologically active than other Galilean moons. Callisto is approximately 4,820.6 km across.
How to observe Callisto
Callisto is resolved as a separate world mainly through imaging or spacecraft data; visually, its relationship to jupiter is the key observing context.
Scientific context
Useful scale comparisons are 0.378 Earth diameters, 0.126 g surface gravity, 0.046 Earth years per orbit. These values are rounded from the catalogue measurements shown on this page.
- Radius
- 2,410.3 km
- Diameter
- 4,820.6 km
- Mass
- 1.08E+23 kg
- Mean density
- 1.841 g/cm³
- Surface gravity
- 1.235 m/s² (0.126 g)
- Orbital period
- 16.689 days (0.046 years)
- Parent body
- jupiter
0.378 Earth diameters0.126 g surface gravity0.046 Earth years per orbit
Source: NASA Science (checked 2026-08-09). Values are rounded catalogue measurements.
Interactive orbit model
Aug 13, 2026, 22:251×
Calculated positions / separate exploration scales