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diff --git a/ast/pal/palEvp.c b/ast/pal/palEvp.c
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+/*
+*+
+*  Name:
+*     palEvp
+
+*  Purpose:
+*     Returns the barycentric and heliocentric velocity and position of the
+*     Earth.
+
+*  Language:
+*     Starlink ANSI C
+
+*  Type of Module:
+*     Library routine
+
+*  Invocation:
+*     void palEvp( double date, double deqx, double dvb[3], double dpb[3],
+*                  double dvh[3], double dph[3] )
+
+*  Arguments:
+*     date = double (Given)
+*        TDB (loosely ET) as a Modified Julian Date (JD-2400000.5)
+*     deqx = double (Given)
+*        Julian epoch (e.g. 2000.0) of mean equator and equinox of the
+*        vectors returned.  If deqx <= 0.0, all vectors are referred to the
+*        mean equator and equinox (FK5) of epoch date.
+*     dvb = double[3] (Returned)
+*        Barycentric velocity (AU/s, AU)
+*     dpb = double[3] (Returned)
+*        Barycentric position (AU/s, AU)
+*     dvh = double[3] (Returned)
+*        heliocentric velocity (AU/s, AU)
+*     dph = double[3] (Returned)
+*        Heliocentric position (AU/s, AU)
+
+*  Description:
+*     Returns the barycentric and heliocentric velocity and position of the
+*     Earth at a given epoch, given with respect to a specified equinox.
+*     For information about accuracy, see the function eraEpv00.
+
+*  Authors:
+*     PTW: Pat Wallace (STFC)
+*     {enter_new_authors_here}
+
+*  History:
+*     2012-02-13 (PTW):
+*        Initial version.
+*        Adapted with permission from the Fortran SLALIB library.
+*     {enter_further_changes_here}
+
+*  Copyright:
+*     Copyright (C) 2005 Patrick T. Wallace
+*     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 "palmac.h"
+#include "pal1sofa.h"
+
+void palEvp( double date, double deqx, double dvb[3], double dpb[3],
+             double dvh[3], double dph[3] ){
+
+/* Local Variables; */
+   int i;
+   double pvh[2][3], pvb[2][3], d1, d2, r[3][3];
+
+/* BCRS PV-vectors. */
+   eraEpv00 ( 2400000.5, date, pvh, pvb );
+
+/* Was precession to another equinox requested? */
+   if ( deqx > 0.0 ) {
+
+/* Yes: compute precession matrix from J2000.0 to deqx. */
+      eraEpj2jd ( deqx, &d1, &d2 );
+      eraPmat06 ( d1, d2, r );
+
+/* Rotate the PV-vectors. */
+      eraRxpv ( r, pvh, pvh );
+      eraRxpv ( r, pvb, pvb );
+   }
+
+/* Return the required vectors. */
+   for ( i = 0; i < 3; i++ ) {
+      dvh[i] = pvh[1][i] / PAL__SPD;
+      dvb[i] = pvb[1][i] / PAL__SPD;
+      dph[i] = pvh[0][i];
+      dpb[i] = pvb[0][i];
+   }
+}