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CONTENTS OF THE DIRECTORY

This directory contains observational data concerning the galilean satellites of
Jupiter from 1891 to 1978. One will find:

1) - File  pos_rela_jup.dat

     Contents:
       - File containing 1138 photographic observations of relative positions of 
         the galilean satellites of Jupiter made on 41 oppositions by 11 obser- 
         vers from 17 sites, from  December 22, 1891 to April 12, 1978. 
         (tangential coordinates in equatorial 1950,0 reference frame),
       - The origin of the coordinates may be the center of mass of all the 
         observed satellites or the observed center of Jupiter.
       - 468 observations from D. Pascu are not include in this file. If you
         want obtained them, you write to the author with this e-mail address,

                U.S. Naval observatory
                34th st and Mass. Ave. NW
                Washington D.C. 20390 USA
                e-mail:"pas@cygnus.usno.navy.mil"
         The periods of these observations are:
            . 1967 December,   4 to 1968 June,      7 ( 95 obs.),
            . 1973 July,      19 to 1973 October,  21 ( 72 obs.),
            . 1974 July,      21 to 1974 December,  6 (123 obs.),
            . 1975 September,  9 to 1975 December,  6 ( 84 obs.),
            . 1976 September,  1 to 1977 February, 11 ( 35 obs.),
            . 1977 October,   31 to 1978 March,    19 ( 59 obs.). 

     Reference: 
         These observations are extracted from,
	 - Arlot, J.-E., 1982, "Amelioration des ephemerides des satellites 
	   galileens de Jupiter par l'analyse des observations", These de 
	   Doctorat d'etat, Obs. de Paris.
  
     Format: 
         This is a sequential file and ne record contains 132 bytes with the 
         following format,

         i4      the year,
         4i2     the month, the day, hours, minutes,
         f4.1    seconds,
         i2      code of the reference frame, 1 = mean terrestrial equatorial 
                                                  frame, 1950,
                                              2 = Jovian equatorial frame of
                                                  the date,
                                              3 = others special frames.
         i2      code of referential center,  1 = center of gravity of observed
                                                  satellites,
                                              2 = center of observed Jupiter.
         i4      code of observatories in the file pos_rela_jup.dat,
         4f11.6  equatorial coordinates of each observed satellite in arcseconds 
                 in X, or - ,in format a11, if the coordinate is absent
         4f11.6  equatorial coordinates of each observed satellite in arcseconds 
                 in Y, or - ,in format a11, if the coordinate is absent
         f8.3    the plate scale in arsecond per millimeter,
         i4      the number of series of observations,
         i4      the code of the observer,
         i4      the number of year of opposition of Jupiter.        

2) - Le fichier tab_vatoir_posjup.dat

     Contents: 
       - 17 names of the sites of observations with the code of them in the file
         pos_rela_jup.dat

     Format:
       - This is a sequential file which has 17 records of 30 bytes with the 
         following format 2a,i4,

         a18   the name of the site of observations,
         a8    "is coded",
         i4    the number of code of the site.

3) - The file tab_vator_posjup.dat

     Contents: 
       - 10 names of observers with the code of them in the file
         pos_rela_jup.dat

     Format:
       - This is a sequential file which has 11 records of 36 bytes with the 
         following format 2a,i4,

         a27   the name of the observer,
         a5    "coded",
         i4    the number of the code of the observer.

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