 vector as a low-accuracy estimate 
         of the apparent position for an application where execution  
         speed is critical: 
 
            Use &quot;NONE&quot;. 
 
 
      6) While this routine cannot perform the relativistic 
         aberration corrections required to compute positions 
         with the highest possible accuracy, it can supply the 
         geometric positions required as inputs to these computations: 
 
            Use &quot;NONE&quot;, then apply relativistic aberration 
   