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Solar System Exploration
Despina: Facts & Figures
   Back to Neptune   Overview   Gallery   Facts & Figures   News 
Discovered By
S. Synnott, Voyager 2
Date of Discovery
Orbit Size Around Neptune (semi-major axis)
Metric: 52,526 km
English: 32,638 miles
Periapsis (closest)
Metric: 52,515 km
Apoapsis (farthest)
Metric: 52,537 km
Sidereal Orbit Period (Length of Year)
0.00091718 Earth years
0.335 Earth days
Average Orbit Velocity
Metric: 41,048.6 km/h
Orbit Eccentricity
Orbit Inclination
0.07 degree
Mean Radius
Metric: 75.0 km
Equatorial Circumference
Metric: 471.2 km
Metric: 1,767,146 km3
Metric: 2,098,135,806,336,070,000 kg
Scientific Notation: 2.0981 x 1018 kg
Metric: 1.3 g/cm3
Surface Area
Metric: 70,685.83 km2
Surface Gravity
Metric: 0.025 m/s2
Escape Velocity
Metric: 220 km/h
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Last Updated: 7 Apr 2014