National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
S/2003 J9: Facts & Figures
   Back to Jupiter   Overview   Facts & Figures 
Discovered By
Scott Sander Sheppard
Date of Discovery
February 2003
Orbit Size Around Jupiter (semi-major axis)
Metric: 23,385,000 km
English: 14,530,765 miles
Periapsis (closest)
Metric: 17,209,022 km
Apoapsis (farthest)
Metric: 29,560,979 km
Sidereal Orbit Period (Length of Year)
2.007693361 Earth years
733.31 Earth days
By Comparison: Retrograde orbit
Orbit Circumference
Metric: 144,335,680.97 km
Average Orbit Velocity
Metric: 8,201.2 km/h
Orbit Eccentricity
Orbit Inclination
By Comparison: Retrograde orbit
Mean Radius
Metric: 0.5 (assuming an albedo of 0.04) km
English: 0.3 miles
Equatorial Circumference
Metric: 3.1 km
Metric: 1 km3
Metric: 1,498,668,433,097 kg
Scientific Notation: 1.4987 x 1012 kg
Metric: 2.6 g/cm3
Surface Area
Metric: 3.14 km2
Surface Gravity
Metric: 0.0004 m/s2
Escape Velocity
Metric: 2 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:
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writers: Courtney O'Connor and Bill Dunford
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> NASA Advisory Council
> Open Government at NASA
Last Updated: 9 Mar 2011