  Typically
   the data are made available by loading kernels; however the
   data may be supplied via subroutine interfaces if applicable.
  
   The following data are required:
 
      - DSK data:  a DSK file containing a plate model representing the
        target body's surface must be loaded. This kernel must contain
        a type 2 segment that contains data for the entire surface of
        the target body.

      - SPK data:  ephemeris data for target, observer, and Sun must be
        loaded.  If 