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Despina: Facts & Figures
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Discovered By
S. Synnott, Voyager 2
Date of Discovery
1989
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)
0.335 Earth days
Average Orbit Velocity
Metric:
41,048.6 km/h
Orbit Eccentricity
0.000
Orbit Inclination
0.07 degree
Mean Radius
Metric:
75.0 km
Equatorial Circumference
Metric:
471.2 km
Volume
Metric:
1,767,146 km
3
Mass
Metric:
2,098,135,806,336,070,000 kg
Scientific Notation:
2.0981 x 10
18
kg
Density
Metric:
1.3 g/cm
3
Surface Area
Metric:
70,685.83 km
2
Surface Gravity
Metric:
0.025 m/s
2
Escape Velocity
Metric:
220 km/h
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Last Updated: 7 Mar 2011