ion invoked by the
                             'LT' option uses one iteration.

                             Both the target state as seen by the
                             observer, and rotation of the target
                             body, are corrected for light time.

                  'XLT+S'    &quot;Transmission&quot; case:  correct for
                             one-way light time and stellar
                             aberration using a Newtonian
                             formulation  