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Solar System Exploration
Hermippe: Facts & Figures
   Back to Jupiter   Overview   Facts & Figures   News 
Discovered By
Scott S. Sheppard, David C. Jewitt, and Jan T. Kleyna
Date of Discovery
9 December 2001
Orbit Size Around Jupiter (semi-major axis)
Metric: 21,300,000 km
English: 13,235,206 miles
Periapsis (closest)
Metric: 16,778,010 km
Apoapsis (farthest)
Metric: 25,821,990 km
Sidereal Orbit Period (Length of Year)
1.735523614 Earth years
633.90 Earth days
By Comparison: Retrograde orbit
Orbit Circumference
Metric: 132,310,864.30 km
Average Orbit Velocity
Metric: 8,696.9 km/h
Orbit Eccentricity
Orbit Inclination
By Comparison: Retrograde orbit
Mean Radius
Metric: 2.0 (assuming an albedo of 0.04) km
English: 1.2 miles
Equatorial Circumference
Metric: 12.6 km
English: 34 mi3
Metric: 89,920,105,985,832 kg
Scientific Notation: 8.9920 x 10 kg
Metric: 2.6 g/cm3
Surface Area
Metric: 50.27 km2
Surface Gravity
Metric: 0.002 m/s2
Escape Velocity
Metric: 9 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

-Ellis Miner

-Encyclopædia Britannica Online. 2010:
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Last Updated: 8 Mar 2011