ADC/CDS Standard Document for Catalog:
/catalogs/1/1227/

IMPORTANT NOTICE:

Superseded  Paris AC Zone Data Reduced to ACRS (+18 to +24) (Urban+ 1996)
================================================================================
Paris AC Zone Data Reduced to ACRS    
   Urban S.E., Jackson E.S., Corbin T.E.
   <unpublished, (1996)>
================================================================================
ADC_Keywords: Astrographic zones; Astrometric data; Historical catalog; 
              Magnitudes, photographic; Photographic catalog; Positional data;
              Regional catalog; Surveys; Cross indentifications 

Abstract:  
  The U.S. Naval Observatory is in the process of making new reductions
  of the Astrographic Catalogue (AC) using a modern reference system, the 
  ACRS, which represents the system of the FK5.
  The data from the Paris Zone, whose plates are centered between
  declinations +18 and +24 degrees (eq. 1900), have been analyzed
  for scale, rotation, tilt, coma, magnitude equation, radial
  distortion and distortions introduced by the use of reseaux in the
  Carte du Ciel program.  The result is a positional catalog of over
  253,000 stars on eq. J2000.0, epoch of observation.  Additionally,
  all stars have been matched with the Tycho Input Catalog (revised);
  those numbers have been added for additional identification purposes.

See also:
 Superseded by catalog 1247:
 1247  The AC2000 Catalogue             (Urban+ 1997)
 at URL ftp://adc.astro.umd.edu/pub/adc/archives/catalogs/1/1247


****SUPERSEDED****
================================================================================