[IGSMAIL-1390] ITRF93/ITRF94 changes

[Dennis]

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IGS Electronic Mail      Tue Jul 16 10:36:43 PDT 1996      Message Number 1390
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Author: Dennis McCarthy
Subject: ITRF93/ITRF94 changes

In order to maintain continuity in the comparisons of the GPS
series to the NEOS combined series, the EOPs for the GPS series
from GPS Week 860 (30 June 1996) on will be transformed back to
the ITRF93 system.  This procedure will be continued for
approximately one month.  At the end of this time, we hope to
have a better feeling for the discrepancies between the
theoretical differences of the ITRF93 to ITRF94 transformation
and the realized differences.  Once the discrepancies are
understood, we will reverse the process so that all EOP before
GPS Week 860 will be transformed from ITRF93 to ITRF94.
--
Dennis D. McCarthy                       dmc at maia.usno.navy.mil
Head, Earth Orientation Department       phone: (202) 762-1837
U.S. Naval Observatory                   fax: (202) 762-1563
Washington, DC 20392-5420


[Mailed From: Dennis McCarthy <dmc at Maia.usno.navy.mil>]