put to the stellar aberration correction. 
 
   When light time and stellar aberration corrections are both 
   applied to a geometric position vector, the resulting position  
   vector indicates where the target &quot;appears to be&quot; from the 
   observer's location.   
 
   As opposed to computing the apparent position of a target, one 
   may wish to compute the pointing direction required for 
   transmission of photons to the target.  This also requires correction 
   of the geometric target posit