Generate the matrix of precession between two epochs, using the old, pre IAU 1976,
Bessel-Newcomb model, in Andoyer’s formulation.
CALL:
CALL sla_PREBN (BEP0, BEP1, RMATP)
GIVEN:
BEP0
D
beginning Besselian epoch
BEP1
D
ending Besselian epoch
RETURNED:
RMATP
D(3,3)
precession matrix
NOTE:
The matrix is in the sense:
v1
= M⋅v0
where v1
is the star vector relative to the mean equator and equinox of epoch BEP1, M is the
3×3 matrix
RMATP and v0
is the star vector relative to the mean equator and equinox of epoch BEP0.