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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 in degrees)                          29.6

Orbit inclination (degrees)                                   1.77

Orbit eccentricity (deviation from circular)         0.009

Mean temperature (K)                                            48

Visual geometric albedo (reflectivity)                  0.51

Atmospheric components:    74% hydrogen, 25% helium, 1% methane (at depth)

Rings:    Rings are narrow, and contain concentrations of particles called ring arcs.


More information about Neptune can be found by clicking here.