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Solar System Exploration
Amalthea: Facts & Figures
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Discovered By
Edward Emerson Barnard
Date of Discovery
Orbit Size Around Jupiter (semi-major axis)
Metric: 181,400 km
English: 112,717 miles
Periapsis (closest)
Metric: 180,820 km
Apoapsis (farthest)
Metric: 181,980 km
Orbit Period (Length of Year)
0.00136345 Earth years
0.498 Earth days
Orbit Circumference
Metric: 1,139,766.90 km
Average Orbit Velocity
Metric: 95,362.0 km/h
Orbit Eccentricity
Orbit Inclination
0.38 degrees
Mean Radius
Metric: 83.45 km
By Comparison: 131 x 73 x 67 km, tri-axial
Equatorial Circumference
Metric: 524.3 km
Metric: 2,434,264 km3
Metric: 2,068,162,437,674,130,000 kg
Scientific Notation: 2.0682 x 1018 kg
Metric: 0.849 g/cm3
Surface Area
Metric: 87,510.98 km2
Surface Gravity
Metric: 0.020 m/s2
Escape Velocity
Metric: 207 km/h
English: 129 mph
Scientific Notation: 58 m/s
Rotation Period (Length of Day)
By Comparison: Synchronous with orbital period
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Last Updated: 12 Aug 2013