During a total so

During an eclipse, the moon entirely covers the sphere of the sun, therefore it can be said that both moon and the sun appear the same size form earth or they subtend the same solid angle on earth. Let ω be the solid angle subtended on earth, in which case we have,

where A_sun and A_moon, are the projected areas of the sun and moon as seen from earth and R_se, and R_{me �} are the distances of sun and moon from earth. Let R_sun and R_moon be the radii of the sun and the moon.

Then we have

Therefore, the distances of sun and moon are relative to their sizes.