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palFk45z

Convert B1950.0 FK4 star data to J2000.0 FK5 assuming zero proper motion in the FK5 frame

Description:

Convert B1950.0 FK4 star data to J2000.0 FK5 assuming zero proper motion in the FK5 frame (double precision)

This function converts stars from the Bessel-Newcomb, FK4 system to the IAU 1976, FK5, Fricke system, in such a way that the FK5 proper motion is zero. Because such a star has, in general, a non-zero proper motion in the FK4 system, the routine requires the epoch at which the position in the FK4 system was determined.

The method is from Appendix 2 of Ref 1, but using the constants of Ref 4.

Invocation

palFk45z( double r1950, double d1950, double bepoch, double r2000, double d2000 )

Arguments

r1950 = double (Given)
B1950.0 FK4 RA at epoch (radians).
d1950 = double (Given)
B1950.0 FK4 Dec at epoch (radians).
bepoch = double (Given)
Besselian epoch (e.g. 1979.3)
r2000 = double (Returned)
J2000.0 FK5 RA (Radians).
d2000 = double (Returned)
J2000.0 FK5 Dec(Radians).

Notes:

References