You have: ((au + (10 mi)) / au) ^ 2 You want: Definition: 1.0000002 (viewing the Sun as a point source located at its center and applying the inve

You have: ((au + (10 mi)) / au) ^ 2 You want: Definition: 1.0000002 (viewing the Sun as a point source located at its center and applying the inverse square law; I'm sure we could find a much better model for this)