===========================                         ============================
                              BUREAU DES LONGITUDES 

		   	     /pub/ephem/satel/posxy

                                1995, February 3
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SATEL/POSXY:      Ephemerides of the main planetary satellites:
                  differential positions of the satellites of Mars,
                  Jupiter,Saturn, Uranus, given under the form of developments
                  in mixed functions.



AUTHORS :         J.-E. Arlot, Ch. Ruatti, D.T. Vu and W. Thuillot


ADDRESS :         Bureau des Longitudes - URA 707 
                  77 av. Denfert Rochereau, F-75014 PARIS
                  Phone: (1) 40 51 22 67  / (1) 40 51 22 65  
                  Fax:   (1) 46 33 28 34 
                  e-mail:arlot@bdl.fr, vu@bdl.fr, ruatti@bdl.fr, thuillot@bdl.fr

CONTENTS:


     diffpos.f  : FORTRAN source to be used with the files of satellites 
                  ephemerides whose names are 'planet.year'. This algorithm 
                  is founded on the mixed function representation by
                  (Chapront and Vu, 1984).                               (12 Ko)

     diffposAix : executable software issued from the compiling of
                  diffpos.f with AIX 3.2.5 & X11R5 1.2.4 system          (31 Ko)

     diffposSun : executable software issued from the compiling of
                  diffpos.f with SunOS Release 4.1.3_U1                 (205 Ko)

     marsbin.YY : Binary file of coefficients of the satellites of Mars, Phobos
                  and Deimos, for the year YY. These coefficients are computed 
                  from the Chapront-Touze's theory (Chapront-Touze, 1990).
                                                                         (20 Ko)

     jupibin.YY : Binary file of coefficients of the Galilean satellites 
                  for the year YY. These coefficients are computed from 
                  the original ephemeride is the G-5 ephemeride (Arlot, 1982)
                  founded on the Sampson-Lieske theory (Sampson 1921, 
                  Lieske, 1977)                                          (55 Ko)
                     
     satubin.YY : Binary file of coefficients of the first eight satellites of
                  Saturn  for the year YY. These coefficients are computed from 
                  the theories of Dourneau (1993), Rapaport (1977), 
                  Kosai (1959) and Struve (1930).                        (55 Ko)
                           
     uranbin.YY : Binary file of coefficients of the five main satellites of 
                  Uranus for the year YY. These coefficients are computed from 
                  the theory of Laskar and Jacobson (Laskar and Jacobson, 1987).
                                                                         (21 Ko)

     example    : Example of an output data for several dates and satellites.
                                                                         (11 Ko)

     seqdir.f   : FORTRAN program for the conversion of ASCII files of 
                  coefficients  in direct access binary files:
                  this program transforms the files named  'planete asc.YY'
                  into the files named 'planete bin.YY' and used by diffpos.f
                                                                          (5 Ko)
     seqdirAix  : executable software issued from the compiling of
                  seqdir.f with AIX 3.2.5 & X11R5 1.2.4 system           (16 Ko)

     seqdirSun  : executable software issued from the compiling of
                  seqdir.f with SunOS Release 4.1.3_U1                  (188 Ko)

     marsasc.YY : ASCII file of the coefficients of the satellites of Mars, 
                  Phobos and Deimos, for the year YY.                    (40 Ko)
                                                                      
     jupiasc.YY : ASCII file of the coefficients of the Galilean satellites of
                  Jupiter for the year YY.                              (110 Ko)

     satuasc.YY : ASCII file of the coefficients of the first eight satellites of
                  Saturn  for the year YY.                              (110 Ko)

     uranasc.YY : ASCII file of the coefficients of the five main satellites of 
                  Uranus for the year YY.                                (41 Ko)


MORE...:

     The input data of diffpos.f are:
     - the date of a beginning of intervall in the Terrestrial Time scale (TT), 
     - the step to use and the number of the planet concerned. 

     The output data are the differential tangential coordinates of the 
     satellites with respect to the center of the planet (in arceseconds). These 
     coordinates are mean equatorial J2000 for all satellites.
     The Y axis is set towards the pole of the equator (North), the X axis 
     towards the increasing right ascensions (East).
 

     The differences between TT and UTC are given in the following table:

     --------------------------------
     period            TT-UTC (sec.)
     --------------------------------
     1/7/94-1/1/96      61.184  
     1/1/96-1/7/97      62.184
     1/7/97-            63.184
     --------------------------------
 

BIBLIOGRAPHY:


Arlot, J.-E.: 1982, Astron. Astrophys. 107, 305

Chapront, J., Vu, D.T.: 1984,  Astron. Astrophys., 141, 131

Chapront-Touze, M.: 1990, 1990, Astron. Astrophys., 240, 159

Dourneau, G.: 1993, Astron. Astrophys., 267, 292

Kosai, Y.: 1959, Astron. J. 64, 367

Laskar, J., Jacobson, R.A.: 1987, Astron. Astrophys. 188, 212.

Lieske, J.H.: 1977, Astron. Astrophys., 56, 333

Rapaport, M.: 1977, Astron. Astrophys., 62, 235

Sampson, R.A.: 1921, Mem. Roy. Astron. Soc. 63

Struve, G.: 1930, Astron. Astrophys., Veroff. Univ. Sternw. Berlin Babelsberg 6.


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