Moon
Janus
TypeMoon
Mass1.898 × 10¹⁸ kg
Diameter179 km
Orbital Radius151,470 km
Orbital Period0.695 days
Rotation Period16.7 hours
Known Moons0
Surface Gravity0.05 m/s²
Average Temp-180 °C
AtmosphereNone
Discovered ByAudouin Dollfus
Discovery Year1966
About Janus
Co-orbital partner of Epimetheus, swapping orbits every four years in a gravitational dance. The two never collide, passing about 10,000 km apart as they trade places. First observed in 1966 and confirmed by Voyager 1 in 1980.
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