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.help fk52h Jun99 "Slalib Package"
.nf

      SUBROUTINE slFK5H (R5,D5,DR5,DD5,RH,DH,DRH,DDH)

     - - - - - -
      F K 5 H
     - - - - - -

  Transform FK5 (J2000) star data into the Hipparcos frame.

  (double precision)

  This routine transforms FK5 star positions and proper motions
  into the frame of the Hipparcos catalogue.

  Given (all FK5, equinox J2000, epoch J2000):
     R5        d      RA (radians)
     D5        d      Dec (radians)
     DR5       d      proper motion in RA (dRA/dt, rad/Jyear)
     DD5       d      proper motion in Dec (dDec/dt, rad/Jyear)

  Returned (all Hipparcos, epoch J2000):
     RH        d      RA (radians)
     DH        d      Dec (radians)
     DRH       d      proper motion in RA (dRA/dt, rad/Jyear)
     DDH       d      proper motion in Dec (dDec/dt, rad/Jyear)

  Called:  slDSC6, slDAVM, slDMXV, slDVXV, slDC6S

  Notes:

  1)  The proper motions in RA are dRA/dt rather than
      cos(Dec)*dRA/dt, and are per year rather than per century.

  2)  The FK5 to Hipparcos transformation consists of a pure
      rotation and spin;  zonal errors in the FK5 catalogue are
      not taken into account.

  3)  The published orientation and spin components are interpreted
      as "axial vectors".  An axial vector points at the pole of the
      rotation and its length is the amount of rotation in radians.

  4)  See also slHFK5, slF5HZ, slHF5Z.

  Reference:

     M.Feissel & F.Mignard, Astron. Astrophys. 331, L33-L36 (1998).

  P.T.Wallace   Starlink   7 October 1998

  Copyright (C) 1998 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

.fi
.endhelp