palSubet
palSubet
- Remove the E-terms from a pre IAU 1976 catalogue RA,Dec
- Description:
- Remove the E-terms (elliptic component of annual aberration)
from a pre IAU 1976 catalogue RA,Dec to give a mean place.
- Invocation:
- void palSubet ( double rc, double dc, double eq,
double
rm, double
dm );
- Arguments:
-
-
rc = double (Given)
-
RA with E-terms included (radians)
-
dc = double (Given)
-
Dec with E-terms included (radians)
-
eq = double (Given)
-
Besselian epoch of mean equator and equinox
-
rm = double
(Returned)
-
RA without E-terms (radians)
-
dm = double
(Returned)
-
Dec without E-terms (radians)
- Notes:
- 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).
-
See Also
- Explanatory Supplement to the Astronomical Ephemeris,
section 2D, page 48.