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Solar System Exploration
Triton: Facts & Figures
   Back to Neptune   Overview   Gallery   Facts & Figures   News 
Discovered By
W. Lassell
Date of Discovery
Orbit Size Around Neptune (semi-major axis)
Metric: 354,759 km
English: 220,437 miles
Periapsis (closest)
Metric: 354,759 km
Apoapsis (farthest)
Metric: 354,759 km
Orbit Period (Length of Year)
0.016090349 Earth years
5.877 Earth days
By Comparison: Retrograde orbit
Orbit Circumference
Metric: 2,229,016.54 km
Average Orbit Velocity
Metric: 15,803.2 km/h
Orbit Eccentricity
Orbit Inclination
156.865 degrees
By Comparison: Retrograde orbit
Mean Radius
Metric: 1353.4 km
Equatorial Circumference
Metric: 8,503.7 km
Metric: 10,384,058,491 km3
Metric: 21,394,990,550,895,500,000,000 kg
Scientific Notation: 2.1395 x 1022 kg
Metric: 2.059 g/cm3
Surface Area
Metric: 23,017,714.99 km2
Surface Gravity
Metric: 0.779 m/s2
Escape Velocity
Metric: 5,229 km/h
English: 3,249 mph
Scientific Notation: 1452 m/s
Rotation Period (Length of Day)
By Comparison: Synchronous with orbital period
Atmospheric Temperature
(at level with pressure = 1 bar)
Scientific Notation: 38 K
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Last Updated: 12 Aug 2013