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Naiad: Facts & Figures
   Back to Neptune   Overview   Gallery   Facts & Figures   News 
Discovered By
Voyager 2
Date of Discovery
1989
Orbit Size Around Neptune (semi-major axis)
Metric: 48,227 km
English: 29,967 miles
Periapsis (closest)
Metric: 48,213 km
Apoapsis (farthest)
Metric: 48,241 km
Orbit Circumference
Metric: 303,019.17 km
Average Orbit Velocity
Metric: 42,944.9 km/h
Orbit Eccentricity
0.0003
Orbit Inclination
4.691 degrees
Mean Radius
Metric: 33.0 km
Equatorial Circumference
Metric: 207.3 km
Volume
Metric: 150,533 km3
Mass
Metric: 194,826,896,302,635,000 kg
Scientific Notation: 1.9483 x 1017 kg
Density
Metric: 1.3 g/cm3
Surface Area
Metric: 13,684.78 km2
Surface Gravity
Metric: 0.012 m/s2
Escape Velocity
Metric: 101 km/h
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Last Updated: 12 Aug 2013