Janus

Moon· orbits Saturn

Janus is a moon orbiting Saturn.

Open in 3D viewSee Janus in the live, interactive 3D map

Key facts

Mass

1.90 × 10¹⁸ kg

0.0000258 Moon masses

Radius

89.2 km

5% of our Moon's radius

Surface gravity

0.0159 m/s²

0% of Earth's

Orbit around Saturn

16.8 hours

0.70 Earth days

Science

Physical

Mass: 1.90 × 10¹⁸ kg · 0.0000258 Moon masses
Radius: 89.2 km · 5% of our Moon's radius
Density: 638 kg/m³ · 0.64× water
Surface gravity: 0.0159 m/s² · 0% of Earth's
Escape velocity: 53.3 m/s · 0% of Earth's

Orbit around Saturn

Distance from Saturn: 4,474,300 km
Orbital period: 16.80 hours
Eccentricity: 0.008697
Inclination: 6.31 °

Radiation & temperature

Insolation: 0.0112 S⊕ · 1% of the sunlight Earth receives

Discovery & history

By: A. Dollfus (1966), D. Pascu (1980)

Janus was discovered in 1966, 1980 by A. Dollfus (1966) and D. Pascu (1980). Saturn's moons are named after giants and deities of world mythology — its distant irregular moons after Norse, Inuit and Gallic figures. Beyond its discovery and naming, little more about it has been individually recorded.

Images

Janus, imaged by Cassini — NASA / JPL / Space Science Institute (public domain) · Wikimedia Commons

Epimetheus Before Janus — NASA/JPL/Space Science Institute · NASA Image Library

Janus from Afar — NASA/JPL-Caltech/Space Science Institute · NASA Image Library

Janus Floats On — NASA/JPL/Space Science Institute · NASA Image Library

Long Shadow, Short Shadow — NASA/JPL/Space Science Institute · NASA Image Library

Across the Encke Gap — NASA/JPL/Space Science Institute · NASA Image Library

So Close… — NASA/JPL/Space Science Institute · NASA Image Library

Small Moon Shadow — NASA/JPL/Space Science Institute · NASA Image Library

Images from open archives · credit shown per image