preces Subroutine

public subroutine preces(tjd1, pos1, tjd2, pos2)

THIS SUBROUTINE PRECESSES EQUATORIAL RECTANGULAR COORDINATES FROM ONE EPOCH TO ANOTHER. THE COORDINATES ARE REFERRED TO THE MEAN DYNAMICAL EQUATOR AND EQUINOX OF THE TWO RESPECTIVE EPOCHS. SEE EXPLANATORY SUPPLEMENT TO THE ASTRONOMICAL ALMANAC, PP. 103-104, AND CAPITAINE ET AL. (2003), ASTRONOMY AND ASTROPHYSICS 412, 567-586.

 TJD1 = TDB JULIAN DATE OF FIRST EPOCH (IN)
 POS1 = POSITION VECTOR, GEOCENTRIC EQUATORIAL RECTANGULAR
        COORDINATES, REFERRED TO MEAN DYNAMICAL EQUATOR AND
        EQUINOX OF FIRST EPOCH (IN)
 TJD2 = TDB JULIAN DATE OF SECOND EPOCH (IN)
 POS2 = POSITION VECTOR, GEOCENTRIC EQUATORIAL RECTANGULAR
        COORDINATES, REFERRED TO MEAN DYNAMICAL EQUATOR AND
        EQUINOX OF SECOND EPOCH (OUT)

NOTE: EITHER TJD1 OR TJD2 MUST BE 2451545.0 (J2000.0) TDB.

Arguments