Lunar limb profiles in comparison with the boundary R_⊙ values: (left) 696,200 km as an upper R_⊙ limit for the local TSE visibility and (right) 699,400 km as a lower R_⊙ limit for the local ASE visibility, following the procedure of Figure 2. Here, we set their boundary conditions where the solar photosphere touches the bottom of (left) the deepest lunar valleys and (right) the top of the lunar mountains.