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.

	Hydra	Pluto
Discovered By	Hal Weaver et al.	Clyde Tombaugh
Date of Discovery	June, 2005	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
Volume	195,432 km3	6,387,259,783 km3
Mass	989,121,165,844,147,000 kg	13,090,000,000,000,000,000,000 kg
Density	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)	38.2 Earth years	247.92065 sidereal years
Mean Orbit Velocity	443.7 km/h	16,809 km/h
Orbit Eccentricity	0.0051	0.2488273
Orbit Inclination to Ecliptic	0.212	17.14 degrees
Orbit Circumference	406,827.32 km	36,529,978,039 km