problem
   becomes a purely geometric one and is described by the diagram above. 

 </PRE>
<h4><a name="Examples">Examples</a></h4>
<PRE>
 
   The numerical results shown for this example may differ across
   platforms. The results depend on the SPICE kernels used as input,
   the compiler and supporting libraries, and the machine specific
   arithmetic implementation.
 
   1) Find the illumination angles at both the sub-observer point and
      sub-solar point on Phobos as seen from Mars for a specified
  