Neptune

Planet Profile

Mass (kg)............................................1.02 x 10^26
Diameter (km)........................................49528
Mean density (kg/m^3) ...............................1640
Escape velocity (m/sec)..............................23300

Average distance from Sun (AU).......................30.06
Rotation period (length of day) (in Earth hours).....19.1
Revolution period (length of year) (in Earth years)..164.8

Obliquity (tilt of axis) (degrees)...................29.6
Orbit inclination (degrees)..........................1.77
Orbit eccentricity...................................0.009

Mean temperature (K).................................48

Visual geometric albedo..............................0.51
Atmospheric components...............................74% hydrogen, 
                                                     25% helium,
                                                      1% methane (at depth)
Rings................................................Rings are 
                          narrow, and contain concentrations of 
			  particles called ring arcs.

LES SATELLITES NATURELS

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