fk52h¶

erfa.fk52h(r5, d5, dr5, dd5, px5, rv5)[source]¶

Transform FK5 (J2000.0) star data into the Hipparcos system.

Parameters:

r5double array
d5double array
dr5double array
dd5double array
px5double array
rv5double array

Returns:

rhdouble array
dhdouble array
drhdouble array
ddhdouble array
pxhdouble array
rvhdouble array

Notes

Wraps ERFA function eraFk52h. The ERFA documentation is:

- - - - - - - - -
 e r a F k 5 2 h
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Transform FK5 (J2000.0) star data into the Hipparcos system.

Given (all FK5, equinox J2000.0, epoch J2000.0):
   r5      double    RA (radians)
   d5      double    Dec (radians)
   dr5     double    proper motion in RA (dRA/dt, rad/Jyear)
   dd5     double    proper motion in Dec (dDec/dt, rad/Jyear)
   px5     double    parallax (arcsec)
   rv5     double    radial velocity (km/s, positive = receding)

Returned (all Hipparcos, epoch J2000.0):
   rh      double    RA (radians)
   dh      double    Dec (radians)
   drh     double    proper motion in RA (dRA/dt, rad/Jyear)
   ddh     double    proper motion in Dec (dDec/dt, rad/Jyear)
   pxh     double    parallax (arcsec)
   rvh     double    radial velocity (km/s, positive = receding)

Notes:

1) This function transforms FK5 star positions and proper motions
   into the system of the Hipparcos catalog.

2) The proper motions in RA are dRA/dt rather than
   cos(Dec)*dRA/dt, and are per year rather than per century.

3) The FK5 to Hipparcos transformation is modeled as a pure
   rotation and spin;  zonal errors in the FK5 catalog are not
   taken into account.

4) See also eraH2fk5, eraFk5hz, eraHfk5z.

Called:
   eraStarpv    star catalog data to space motion pv-vector
   eraFk5hip    FK5 to Hipparcos rotation and spin
   eraRxp       product of r-matrix and p-vector
   eraPxp       vector product of two p-vectors
   eraPpp       p-vector plus p-vector
   eraPvstar    space motion pv-vector to star catalog data

Reference:

   F.Mignard & M.Froeschle, Astron.Astrophys., 354, 732-739 (2000).

This revision:  2021 May 11

Copyright (C) 2013-2023, NumFOCUS Foundation.
Derived, with permission, from the SOFA library.  See notes at end of file.

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fk52h¶