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Solar System Exploration
Deimos: Facts & Figures
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Discovered By
A. Hall
Date of Discovery
Orbit Size Around Mars (semi-major axis)
Metric: 23,458 km
English: 14,576 miles
Periapsis (closest)
Metric: 23,453 km
Apoapsis (farthest)
Metric: 23,463 km
Sidereal Orbit Period (Length of Year)
0.003456263 Earth years
1.2624 Earth days
Orbit Circumference
Metric: 147,390.96 km
Average Orbit Velocity
Metric: 4,864.8 km/h
Orbit Eccentricity
Orbit Inclination
1.788 degrees
Mean Radius
Metric: 6.2 km
By Comparison: 7.5 x 6.1 x 5.2 km, tri-axial shape
Equatorial Circumference
Metric: 39.0 km
Metric: 998 km3
Metric: 1,476,188,406,600,740 kg
Scientific Notation: 1.4762 x 1015 kg
Metric: 1.471 g/cm3
Surface Area
Metric: 483.05 km2
Surface Gravity
Metric: 0.003 m/s2
Escape Velocity
Metric: 20 km/h
English: 13 mph
Scientific Notation: 6 m/s
Rotation Period (Length of Day)
1.2624 Earth days
30.2976 hours
By Comparison: Synchronous with orbital period
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Last Updated: 6 Mar 2014