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Solar System Exploration
Laomedeia: Facts & Figures
   Back to Neptune   Overview   Gallery   Facts & Figures 
Discovered By
Matthew J. Holman, John J. Kavelaars, Tommy Grav, Wesley C. Fraser, and Dan Milisavljevic
Date of Discovery
13 August 2002
Orbit Size Around Neptune (semi-major axis)
Metric: 23,567,000 km
English: 14,643,855 miles
Scientific Notation: 2.3567x107 km
Periapsis (closest)
Metric: 14,213,258 km
Apoapsis (farthest)
Metric: 32,920,742 km
Sidereal Orbit Period (Length of Year)
8.682628337 Earth years
3,171.33 Earth days
Orbit Circumference
Metric: 142,059,611.72 km
Average Orbit Velocity
Metric: 1,866.5 km/h
Orbit Eccentricity
Orbit Inclination
Mean Radius
Metric: 21.0 (assuming an albedo of 0.04) km
English: 13.0 miles
Equatorial Circumference
Metric: 131.9 km
Metric: 38,792 km3
Metric: 89,920,105,985,831,600 kg
Scientific Notation: 8.9920x1016 kg
Metric: 1.5 g/cm3
Surface Area
Metric: 5,541.77 km2
Surface Gravity
Metric: 0.014 m/s2
Escape Velocity
Metric: 86 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: 7 Mar 2011