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Solar System Exploration
Eris: Facts & Figures
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Discovered By
M. E. Brown, C. A. Trujillo and D. Rabinowitz
Date of Discovery
21 Oct. 2003
Orbit Size Around Sun (semi-major axis)
Metric: 10,180,122,852 km
English: 6,325,635,074 miles
Scientific Notation: 1.0180123 x 1010 km (6.8049918 x 101 A.U.)
By Comparison: 68.050
Perihelion (closest)
Metric: 5,765,732,799 km
English: 3,582,660,264 miles
Scientific Notation: 5.76573 x 109 km (3.854 x 101 A.U.)
Aphelion (farthest)
Metric: 14,594,512,904 km
English: 9,068,609,883 miles
Scientific Notation: 1.45945 x 1010 km (9.756 x 101 A.U.)
Sidereal Orbit Period (Length of Year)
561.37 Earth years
Orbit Circumference
Metric: 60,841,487,025 km
English: 37,805,147,330 miles
Scientific Notation: 6.084 x 1010 km
By Comparison: 64.733
Average Orbit Velocity
Metric: 12,364 km/h
English: 7,682 mph
Scientific Notation: 3.4344 x 103 m/s
Orbit Eccentricity
By Comparison: 25.948
Orbit Inclination
Sidereal Rotation Period (Length of Day)
1.079 Earth days
25.90000 hours
By Comparison: 1.08
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Last Updated: 20 Apr 2015