slaSubet -

SYNOPSYS

void slaSubet(rc, dc, eq, rm, dm)

PARAMETERS

double rc
double dc
double eq
double *rm
double *dm

DESCRIPTION


  Remove the e-terms (elliptic component of annual aberration)
  from a pre IAU 1976 catalogue RA,Dec to give a mean place.

  (double precision)

Given

     rc,dc     double     RA,Dec (radians) with e-terms included
     eq        double     Besselian epoch of mean equator and equinox

Returned

     *rm,*dm   double     RA,Dec (radians) without e-terms

Called

     slaEtrms, slaDcs2c, sla,dvdv, slaDcc2s, slaDranrm

Explanation

     Most star positions from pre-1984 optical catalogues (or
     derived from astrometry using such stars) embody the
     e-terms.  This routine converts such a position to a
     formal mean place (allowing, for example, comparison with a
     pulsar timing position).

Reference

     Explanatory Supplement to the Astronomical Ephemeris,
     section 2D, page 48.

  P.T.Wallace   Starlink   31 October 1993

SEE ALSO