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authorJoe Hunkeler <jhunkeler@gmail.com>2015-08-11 16:51:37 -0400
committerJoe Hunkeler <jhunkeler@gmail.com>2015-08-11 16:51:37 -0400
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+.help fk5hz Jun99 "Slalib Package"
+.nf
+
+ SUBROUTINE slF5HZ (R5,D5,EPOCH,RH,DH)
+
+ - - - - - -
+ F 5 H Z
+ - - - - - -
+
+ Transform an FK5 (J2000) star position into the frame of the
+ Hipparcos catalogue, assuming zero Hipparcos proper motion.
+
+ (double precision)
+
+ This routine converts a star position from the FK5 system to
+ the Hipparcos system, in such a way that the Hipparcos proper
+ motion is zero. Because such a star has, in general, a non-zero
+ proper motion in the FK5 system, the routine requires the epoch
+ at which the position in the FK5 system was determined.
+
+ Given:
+ R5 d FK5 RA (radians), equinox J2000, epoch EPOCH
+ D5 d FK5 Dec (radians), equinox J2000, epoch EPOCH
+ EPOCH d Julian epoch (TDB)
+
+ Returned (all Hipparcos):
+ RH d RA (radians)
+ DH d Dec (radians)
+
+ Called: slDS2C, slDAVM, slDIMV, slDMXV, slDC2S
+
+ Notes:
+
+ 1) The FK5 to Hipparcos transformation consists of a pure
+ rotation and spin; zonal errors in the FK5 catalogue are
+ not taken into account.
+
+ 2) 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.
+
+ 3) See also slFK5H, slHFK5, 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