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 DATA / PRODUCTS >  ICRF

The International Celestial Reference Frame (ICRF)

The International Celestial Reference Frame (ICRF) realizes an ideal reference system, the International Celestial Reference System (ICRS), by precise equatorial coordinates of extragalactic radio sources observed in Very Long Baseline Interferometry (VLBI) programmes. The Hipparcos catalogue which includes all the FK5 stars was astrometically aligned to ICRF and provides the primary realization of ICRS at optical wavelengths.

Contents   Equatorial coordinates of 608 extragalactic radio sources in J2000.0 observed with VLBI.
 
Accuracy   Uncertainties are given in the file.
   R.A. [s]  
  0.000017-   0.092072
   Dec. ["]  
  0.00026-   0.9467
 
Updates   First extension of the ICRF (ICRF-Ext.1)
 
Public access      
   ICRF     http://hpiers.obspm.fr/icrs-pc/ or
    ftp://hpiers.obspm.fr/iers/icrs-pc/icrf/
   ICRF + ICRF Ext. 1     http://hpiers.obspm.fr/icrs-pc/ or
    ftp://hpiers.obspm.fr/iers/icrs-pc/icrf/
 
Format   For format description see contents of the data file.
 
Documentation    
-  IERS Technical Note No. 23 (out of print!)
-  C. Ma et al.: The International Celestial Reference Frame as Realized by Very Long Baseline Interferometry (AJ, 1998, 116, 516-546)
-  http://hpiers.obspm.fr/icrs-pc/
-  http://rorf.usno.navy.mil/ICRF/
 
Product Centre   IERS ICRS Centre