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Larissa: Facts & Figures
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Discovered By
H. Reitsema, W. Hubbard, L. Lebofsky, D. Tholen
Date of Discovery
1982
Orbit Size Around Neptune (semi-major axis)
Metric: 73,548 km
English: 45,701 miles
Periapsis (closest)
Metric: 73,445 km
Apoapsis (farthest)
Metric: 73,651 km
Sidereal Orbit Period (Length of Year)
0.001519507 Earth years
0.555 Earth days
Orbit Circumference
Metric: 462,115.49 km
Average Orbit Velocity
Metric: 34,693.4 km/h
Orbit Eccentricity
0.0014
Orbit Inclination
0.205 degree
Mean Radius
Metric: 97.0 km
By Comparison: 104 x 89 km, ellipsoidal
Equatorial Circumference
Metric: 609.5 km
Volume
Metric: 3,822,996 km3
Mass
Metric: 4,945,605,829,220,740,000 kg
Scientific Notation: 4.9456 x 1018 kg
Density
Metric: 1.3 g/cm3
Surface Area
Metric: 118,236.98 km2
Surface Gravity
Metric: 0.035 m/s2
Escape Velocity
Metric: 297 km/h
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Last Updated: 6 Feb 2014