palMappa palMappa - Compute parameters needed by palAmpqk and palMapqk

Description:
Compute star-independent parameters in preparation for transformations between mean place and geocentric apparent place.

The parameters produced by this function are required in the parallax, aberration, and nutation/bias/precession parts of the mean/apparent transformations.

The reference systems and timescales used are IAU 2006.


Invocation:
void palMappa( double eq, double date, double amprms[21] )

Arguments:

eq = double (Given)
epoch of mean equinox to be used (Julian)
date = double (Given)
TDB (JD-2400000.5)
amprms = double[21] (Returned)
star-independent mean-to-apparent parameters:
  • (0) time interval for proper motion (Julian years)

  • (1-3) barycentric position of the Earth (AU)

  • (4-6) heliocentric direction of the Earth (unit vector)

  • (7) (grav rad Sun)$*$2/(Sun-Earth distance)

  • (8-10) abv: barycentric Earth velocity in units of c

  • (11) sqrt(1-v$*$$*$2) where v=modulus(abv)

  • (12-20) precession/nutation (3,3) matrix


Notes: