SLA_SUBET - Remove E-terms   

ACTION:

Remove the E-terms (elliptic component of annual aberration) from a pre IAU 1976 catalogue $[\,\alpha,\delta\,]$ to give a mean place.

CALL:

CALL sla_SUBET (RC, DC, EQ, RM, DM)

GIVEN:

$$[\,\alpha,\delta\,]$$ RC,DC

EQ D Besselian epoch of mean equator and equinox

RETURNED:

$$[\,\alpha,\delta\,]$$ RM,DM

NOTE:

Most star positions from pre-1984 optical catalogues (or obtained by astrometry with respect to such stars) have the E-terms built-in. 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.