EPHEM

                                                                                
----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
EPHEM         200                                                               
----+----0----+----0----+----0----+----0----+----0----+----0----+----0----+----0
                                                                                
                                                                                
COLUMNS FORMAT         DESCRIPTION                         DEFAULT VALUE & UNITS
                                                                                
1-6     A6     EPHEM - Tells GEODYN which ephemeris                             
               is being input on unit #1. This                                  
               card is required to select the                                   
               DE118 ephemeris and is optional                                  
               for the DE96 and DE200 ephemerides.                              
                                                                                
15-17   I3     Ephemeris indicator as follows:                   200            
                                                                                
               = 96 - DE96 ephemeris using mean                                 
                      equator and equinox of 1950                               
                      and Woolard's nutations                                   
                      series.                                                   
                                                                                
               =118 - DE118 ephemeris using mean                                
                      equator and equinox of 1950                               
                      coordinates and Wahr's                                    
                      nutations series.                                         
                                                                                
                                                                                
               =200 - DE200 ephemeris using mean                                
                      equator and equinox of 2000                               
                      coordinates and Wahr series                               
                      nutations. The selection of                               
                      the DE200 ephemeris also                                  
                      causes different precession                               
                      and Greenwich Mean Sidereal                               
                      Time(GMST) calculations.
AUG 1985

8507.0

GLOBAL SET

EPHEM (cont)

                                                                                
 NOTE:  GEODYN is unable to distinguish between the DE118 and DE200             
        ephemerides without this option card, but it is able to distinguish     
        between the DE96 and the later DE118 and DE200 ephemerides. Thus        
        this card is REQUIRED only when the DE118 ephemeris is selected. For    
        the DE96 and DE200 ephemeris the program will determine which           
        ephemeris is actually supplied on unit #1                               
                                                                                
                                                                                
                                                                                
                                                                                
IF CARD OMITTED:  DE200 ephemeris is assumed input on UNIT 1. If a DE96         
                  ephemeris is input on UNIT 1 and this option card is          
                  not present, GEODYN will reject the DE96 ephemeris and        
                  function properly.
JUNE 1989

8906.0

GLOBAL SET



Patrick Dahiroc
1998-09-10