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Solar System Exploration
Ananke: Facts & Figures
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Discovered By
Seth Barnes Nicholson
Date of Discovery
28 September 1951
Orbit Size Around Jupiter (semi-major axis)
Metric: 21,276,000 km
English: 13,220,293 miles
Scientific Notation: 2.1276x107 km (1.4222x10-1 A.U.)
Periapsis (closest)
Metric: 16,095,294 km
Apoapsis (farthest)
Metric: 26,456,706 km
Sidereal Orbit Period (Length of Year)
1.72421629 Earth years
629.77 Earth days
By Comparison: Retrograde orbit
Orbit Circumference
Metric: 131,676,895.83 km
Average Orbit Velocity
Metric: 8,712.0 km/h
Orbit Eccentricity
Orbit Inclination
By Comparison: Retrograde orbit
Mean Radius
Metric: 14.0 (assuming an albedo of 0.04) km
English: 8.7 miles
Scientific Notation: 1.4x101 km
Equatorial Circumference
Metric: 88.0 km
Metric: 11,494 km3
Metric: 29,973,368,661,943,900 kg
Scientific Notation: 2.9973x1016 kg
Metric: 2.6 g/cm3
Surface Area
Metric: 2,463.01 km2
Surface Gravity
Metric: 0.010 m/s2
Escape Velocity
Metric: 61 km/h
English: 38 mph
Scientific Notation: 17 m/s

Additional Information:

-USGS Astrogeology: Gazetteer of Planetary Nomenclature:

-JPL Solar System Dynamics:

-Solar System Moons: Discovery and Mythology by Jürgen Blunck; Springer-Verlag Berlin Heidelberg 2010

-Encyclopedia of the Solar System, second edition; edited by Lucy-Ann McFadden, Paul R. Weissman, and Torrence V. Johnson; Academic Press 2007

-Ellis Miner

-Encyclopædia Britannica Online. 2010:
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Last Updated: 25 Apr 2012