International Astronomical Union IERS / International VLBI Service

The International Celestial Reference Frame

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Adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1 January 1998.


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2009 August 13: The XXVII IAU General Assembly approved without dissent Resolution B3 adopting the ICRF2 as the fundamental celestial reference frame as of 1 January 2010. A complete description of ICRF2 is available in IERS Technical Note 35.

2006 Aug-Dec: Working groups for ICRF2 are formed.

2004 Jun: ICRF-Ext.2, the second extension of the International Celestial Reference Frame is released. The manuscript "The Second Extension of the International Celestial Reference Frame: ICRF-Ext.2," by A. Fey et al. is published in The Astronomical Journal (AJ, 2004, 127, 3587).

1999 Jul: ICRF-Ext.1 is released.

1998 Jul: The manuscript "The International Celestial Reference Frame as Realized by Very Long Baseline Interferometry," by C. Ma et al. is published in The Astronomical Journal (AJ, 1998, 116, 516).

1998 Mar: The manuscript "The International Celestial Reference Frame as Realized by Very Long Baseline Interferometry," by C. Ma et al. is accepted for publication in The Astronomical Journal. A preprint is available. PostScript (3485kb)

1998 Jan: The ICRS becomes the IAU celestial reference system. The ICRF replaces the FK5 optical frame as the fundamental celestial reference frame. The "Maintenance of the ICRF" World Wide Web page is created.

1997 Aug: The ICRF is presented to the IAU at the Kyoto General Assembly and accepted by the IAU as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1 January 1998.

1997 Jun: IERS Technical Note No 23, "The Definition and Realization of the International Celestial Reference System by VLBI Astrometry of Extragalactic Objects," is published; C. Ma and M. Feissel (eds)


Last modified: Tue Dec 19 08:42:18 EST 2006
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