NAME:
  paracorr
 PURPOSE:   (one line only)
  Take raw Gaia catalog data information and apply correction to a time
 DESCRIPTION:
 CATEGORY:
  Astrometry
 CALLING SEQUENCE:
  paracorr,info
 INPUTS:
  jd - UT Julian date to correct the catalog positions to
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
  FNCAT - Optional file name to read, default is star.cat.gcat
 OUTPUTS:
  info - anonymous structure with the information from the input file
           and the correction position(s)
 KEYWORD OUTPUT PARAMETERS:
 CONFIGURATION:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  2021/01/27, Written by Marc W. Buie, Southwest Research Institute
  2022/06/21, MWB, added DR3 pm bias correction.
  2022/06/22, MWB, changed to earth center, not barycenter, and J2000 coords
  2022/08/29, MWB, changed to heliocenter, not SS barycenter