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SUBROUTINE sla_MAP (RM, DM, PR, PD, PX, RV, EQ, DATE, RA, DA)
*+
* - - - -
* M A P
* - - - -
*
* Transform star RA,Dec from mean place to geocentric apparent
*
* The reference frames and timescales used are post IAU 1976.
*
* References:
* 1984 Astronomical Almanac, pp B39-B41.
* (also Lederle & Schwan, Astron. Astrophys. 134,
* 1-6, 1984)
*
* Given:
* RM,DM dp mean RA,Dec (rad)
* PR,PD dp proper motions: RA,Dec changes per Julian year
* PX dp parallax (arcsec)
* RV dp radial velocity (km/sec, +ve if receding)
* EQ dp epoch and equinox of star data (Julian)
* DATE dp TDB for apparent place (JD-2400000.5)
*
* Returned:
* RA,DA dp apparent RA,Dec (rad)
*
* Called:
* sla_MAPPA star-independent parameters
* sla_MAPQK quick mean to apparent
*
* Notes:
*
* 1) EQ is the Julian epoch specifying both the reference
* frame and the epoch of the position - usually 2000.
* For positions where the epoch and equinox are
* different, use the routine sla_PM to apply proper
* motion corrections before using this routine.
*
* 2) The distinction between the required TDB and TT is
* always negligible. Moreover, for all but the most
* critical applications UTC is adequate.
*
* 3) The proper motions in RA are dRA/dt rather than
* cos(Dec)*dRA/dt.
*
* 4) This routine may be wasteful for some applications
* because it recomputes the Earth position/velocity and
* the precession/nutation matrix each time, and because
* it allows for parallax and proper motion. Where
* multiple transformations are to be carried out for one
* epoch, a faster method is to call the sla_MAPPA routine
* once and then either the sla_MAPQK routine (which includes
* parallax and proper motion) or sla_MAPQKZ (which assumes
* zero parallax and proper motion).
*
* P.T.Wallace Starlink 19 January 1993
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION RM,DM,PR,PD,PX,RV,EQ,DATE,RA,DA
DOUBLE PRECISION AMPRMS(21)
* Star-independent parameters
CALL sla_MAPPA(EQ,DATE,AMPRMS)
* Mean to apparent
CALL sla_MAPQK(RM,DM,PR,PD,PX,RV,AMPRMS,RA,DA)
END
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