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                         IMCCE - Observatoire de Paris

                               PRECESSION PRCBDL94

                                  December 1997
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These files and programs are associated to :

Numerical expressions for precession formulae and mean elements
for the Moon and the planets.
    Simon J.L., Bretagnon P., Chapront J., Chapront-Touze M.,
    Francou G., Laskar J.
    Astron. Astrophys. 282, 663 (1994).

Authors' Address:

    IMCCE - Observatoire de Paris
    77, Avenue Denfert-Rochereau
    75014, Paris, France.

Contents

    The expressions for the precession quantities use the secular variations
    of the ecliptic pole defined by the planetary theories built at the
    Bureau des longitudes.
    A set of formulae allow to update these expressions with new values of
    the planetary masses, precession constant and obliquity J2000.

File Summary:

-------------------------------------------------------------------------
 FileName    Lrecl    Records   Explanations
-------------------------------------------------------------------------
README          80        .     This file.
prctable.doc    80      152     Table of precession quantities BDL94.
prcbdl94.f      80      279     Fortran77 code : compute precession
                                quantities with formulae BDL94.
prcupdat.f      80      504     Fortran77 code : improve the numerical
                                expressions of precession BDL94 with new
                                values for general precession, obliquity
                                and ratios Sun mass / planet mass.
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