Pluto

Discovered by	Clyde W. Tombaugh
Date of discovery	February 18, 1930
Mass (kg)	1.27e+22
Mass (Earth = 1)	2.125e-03
Equatorial radius (km)	1,137
Equatorial radius (Earth = 1)	0.1783
Mean density (gm/cm^3)	2.05
Mean distance from the Sun (km)	5,913,520,000
Mean distance from the Sun (Earth = 1))	39.5294
Rotational period (days)	-6.3872
Orbital period (years)	248.54
Mean orbital velocity (km/sec)	4.74
Orbital eccentricity	0.2482
Tilt of axis (degrees)	122.52
Orbital inclination (degrees)	17.148
Equatorial surface gravity (m/sec^2)	0.4
Equatorial escape velocity (km/sec)	1.22
Visual geometric albedo	0.3
Magnitude (Vo)	15.12
Atmospheric composition Methane Nitrogen	0.3