`"Mean Distance"_("Neptune") = 30.156 "AU"`

30.156

The Mean Elliptical Radius from the planet Neptune to the Sun is 30.156 au.

The Math / Science

The orbit of Neptune around the Sun traces an elliptical path with closest approach (perihelion) of 29.81 AU, and a furthest approach (aphelion) of 30.33 AU.

The formula for the mean radius of an ellipse is:

       `r_u = (2 a +b)/3`

where:

• r_u is the mean radius of the ellipse
• a is the length of the semi-major axis
• b is the length of the semi-minor axis.