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Solar System Exploration
Arche: Facts & Figures
   Back to Jupiter   Overview   Facts & Figures 
Discovered By
Scott S. Sheppard
Date of Discovery
Orbit Size Around Jupiter (semi-major axis)
Metric: 23,355,000 km
English: 14,512,124 miles
Periapsis (closest)
Metric: 17,387,798 km
Apoapsis (farthest)
Metric: 29,322,203 km
Sidereal Orbit Period (Length of Year)
2.003832991 Earth years
731.90 Earth days
By Comparison: Retrograde orbit
Orbit Circumference
Metric: 144,318,784.67 km
Average Orbit Velocity
Metric: 8,216.0 km/h
Orbit Eccentricity
Orbit Inclination
By Comparison: Retrograde orbit
Mean Radius
Metric: 1.5 (assuming an albedo of 0.04) km
English: 0.9 miles
Equatorial Circumference
Metric: 9.4 km
Metric: 14 km3
Metric: 44,960,052,992,916 kg
Scientific Notation: 4.4960 x 1013 kg
Metric: 2.6 g/cm3
Surface Area
Metric: 28.27 km2
Surface Gravity
Metric: 0.001 m/s2
Escape Velocity
Metric: 7 km/h

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

- Dr. Ellis Miner, retired planetary scientist, Jet Propulsion Laboratory

-Encyclopædia Britannica Online. 2010:
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Last Updated: 24 Mar 2011