    sequence of times. Perform each computation twice, using both the
      &quot;intercept&quot; and &quot;ellipsoid near point&quot; options for the sub-observer
      point and sub-solar point computations. Compute the corresponding
      illumination angles using an ellipsoidal surface for comparison.
      (Note that the surface points on the plate model generally will
      not lie on the ellipsoid's surface, so the emission and solar
      incidence angles won't generally be zero at the sub-observer
