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Solar
Moon

Io

Orbital elements

Semi-major axis
0.003 AU
Eccentricity
0.0041
Inclination
0.05°
Orbital period
42.5 hours
Epoch · J2000
J2000

Physical properties

Mean radius
1,822 km
Mass
8.932 × 10²² kg
Density
3.528 g/cm³
Rotation period
42.46 hours
Surface gravity
1.8 m/s²

Visual & observation

Geometric albedo
0.63
Representative colour
#E3D27E

Discovery & classification

Discovered by
Galileo Galilei
Discovery date
8 January 1610

Sources