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Celestial Reference Frame


Celestial Reference Frame (CRF)

The Celestial Reference Frame product consists of milli-arcsecond accurate astrometric positions of extragalactic radio sources.


VLBI solutions from which the above products are derived including explanations, comparisons and format information.

Celestial Reference Frame
Terrestrial Reference Frame
Global VLBI Solution crf2008b Global VLBI TRF/EOP Solution 2008b


USNO Master Clock Time
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