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Iapetus: Facts & Figures
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Discovered By
G.D. Cassini
Date of Discovery
Orbit Size Around Saturn (semi-major axis)
Metric: 3,560,851 km
English: 2,212,610 miles
Periapsis (closest)
Metric: 3,456,518 km
Apoapsis (farthest)
Metric: 3,665,184 km
Sidereal Orbit Period (Length of Year)
0.217193703 Earth years
79.33 Earth days
Orbit Circumference
Metric: 22,368,684.06 km
Average Orbit Velocity
Metric: 11,748.8 km/h
Orbit Eccentricity
Orbit Inclination
8.313 degrees
Mean Radius
Metric: 735.6 km
Equatorial Circumference
Metric: 4,621.9 km
Metric: 1,667,300,080 km3
Metric: 1,805,952,411,282,580,000,000 kg
Scientific Notation: 1.8060 x 1021 kg
Metric: 1.083 g/cm3
Surface Area
Metric: 6,799,755.63 km2
Surface Gravity
Metric: 0.223 m/s2
Escape Velocity
Metric: 2,061 km/h
Rotation Period (Length of Day)
By Comparison: Synchronous with orbital period
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Last Updated: 12 Aug 2013