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diff --git a/ast/pal/palRvlsrk.c b/ast/pal/palRvlsrk.c
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+/*
+*+
+*  Name:
+*     palRvlsrk
+
+*  Purpose:
+*     Velocity component in a given direction due to the Sun's motion
+*     with respect to an adopted kinematic Local Standard of Rest.
+
+*  Language:
+*     Starlink ANSI C
+
+*  Type of Module:
+*     Library routine
+
+*  Invocation:
+*     double palRvlsrk( double r2000, double d2000 )
+
+*  Arguments:
+*     r2000 = double (Given)
+*        J2000.0 mean RA (radians)
+*     d2000 = double (Given)
+*        J2000.0 mean Dec (radians)
+
+*  Returned Value:
+*     Component of "standard" solar motion in direction R2000,D2000 (km/s).
+
+*  Description:
+*     This function returns the velocity component in a given direction
+*     due to the Sun's motion with respect to an adopted kinematic
+*     Local Standard of Rest. The result is +ve when the Sun is receding
+*     from the given point on the sky.
+
+*  Notes:
+*     - The Local Standard of Rest used here is one of several
+*     "kinematical" LSRs in common use.  A kinematical LSR is the mean
+*     standard of rest of specified star catalogues or stellar
+*     populations.  The Sun's motion with respect to a kinematical LSR
+*     is known as the "standard" solar motion.
+*     - There is another sort of LSR, the "dynamical" LSR, which is a
+*     point in the vicinity of the Sun which is in a circular orbit
+*     around the Galactic centre.  The Sun's motion with respect to
+*     the dynamical LSR is called the "peculiar" solar motion.  To
+*     obtain a radial velocity correction with respect to the
+*     dynamical LSR use the routine sla_RVLSRD.
+
+*  Reference:
+*     - Delhaye (1965), in "Stars and Stellar Systems", vol 5, p73.
+
+*  Authors:
+*     PTW: Pat Wallace (STFC)
+*     DSB: David Berry (JAC, Hawaii)
+*     {enter_new_authors_here}
+
+*  History:
+*     2012-02-16 (DSB):
+*        Initial version.
+*        Adapted with permission from the Fortran SLALIB library.
+*     {enter_further_changes_here}
+
+*  Copyright:
+*     Copyright (C) 1995 Rutherford Appleton Laboratory
+*     Copyright (C) 2012 Science and Technology Facilities Council.
+*     All Rights Reserved.
+
+*  Licence:
+*     This program is free software: you can redistribute it and/or
+*     modify it under the terms of the GNU Lesser General Public
+*     License as published by the Free Software Foundation, either
+*     version 3 of the License, or (at your option) any later
+*     version.
+*
+*     This program is distributed in the hope that it will be useful,
+*     but WITHOUT ANY WARRANTY; without even the implied warranty of
+*     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*     GNU Lesser General Public License for more details.
+*
+*     You should have received a copy of the GNU Lesser General
+*     License along with this program.  If not, see
+*     <http://www.gnu.org/licenses/>.
+
+*  Bugs:
+*     {note_any_bugs_here}
+*-
+*/
+
+#include "pal.h"
+#include "pal1sofa.h"
+
+double palRvlsrk( double r2000, double d2000 ){
+
+/* Local Variables: */
+   double vb[ 3 ];
+
+/*
+*  Standard solar motion (from Methods of Experimental Physics, ed Meeks,
+*  vol 12, part C, sec 6.1.5.2, p281):
+*
+*  20 km/s towards RA 18h Dec +30d (1900).
+*
+*  The solar motion is expressed here in the form of a J2000.0
+*  equatorial Cartesian vector:
+*
+*      VA(1) = X = -SPEED*COS(RA)*COS(DEC)
+*      VA(2) = Y = -SPEED*SIN(RA)*COS(DEC)
+*      VA(3) = Z = -SPEED*SIN(DEC)
+*/
+
+   double va[ 3 ] = { -0.29000, +17.31726, -10.00141 };
+
+/* Convert given J2000 RA,Dec to x,y,z. */
+   eraS2c( r2000, d2000, vb );
+
+/* Compute dot product with Solar motion vector. */
+   return eraPdp( va, vb );
+}