Solid.AddSphere

void AddSphere(float diameter, float kilograms, Nullable`1 offset)

   
float diameter Twice the radius of the sphere! The total size, in meters!
float kilograms How many kilograms does this shape weigh?
Nullable`1 offset Offset ot this shape from the center of the solid.

This adds a sphere to this solid’s physical shape! This is in addition to any other shapes you’ve added to this solid.