Brief_I/O">Brief_I/O</a></h4>
<PRE>
 
   Variable  I/O  Description 
   --------  ---  -------------------------------------------------- 
   targ       I   Target body name. 
   et         I   Observer epoch. 
   ref        I   Reference frame of output position vector. 
   abcorr     I   Aberration correction flag. 
   obs        I   Observing body name. 
   ptarg      O   Position of target. 
   lt         O   One way light time between observer and target. 
 </PRE>
<h4><a name="Detailed_Input">Detailed_