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Comparison Chart
Comparison: Hydra vs. Pluto

This chart shows the differences between Hydra and Pluto. To change the planets/moons being compared, change one or more of the form fields at the bottom and click Refresh.

Discovered By
Hal Weaver et al.
Clyde Tombaugh
Date of Discovery
June, 2005
18 Feb 1930
Average Orbit Distance
64,749 km
5,906,440,628 km
Perihelion/Perigee (closest)
64,419 km
4,436,756,954 km
Aphelion/Apogee (farthest)
65,079 km
7,376,124,302 km
Equatorial Radius
36 km
1,151 km
Equatorial Circumference
226.2 km
7,231.9 km
195,432 km3
6,387,259,783 km3
989,121,165,844,147,000 kg
13,032,000,000,000,000,000,000 kg
5 g/cm3
2.050 g/cm3
Surface Area
16,286.02 km2
16,647,940 km2
Equatorial Surface Gravity
0.051 m/s2
0.66 m/s2
Escape Velocity
218 km/h
4,428 km/h
Orbit Period (Length of Year)
0.1045859 Earth years
247.92065 sidereal years
Mean Orbit Velocity
443.7 km/h
16,809 km/h
Orbit Eccentricity
Orbit Inclination to Ecliptic
17.14 degrees
Orbit Circumference
406,827.32 km
36,529,978,039 km


New planets/moons to compare:

System of measurement:

Compare All Eight Planets

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Last Updated: 17 Jul 2015