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IERS Message No. 143                                      April 16, 2009
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Information on the updates to the IERS Conventions


The IERS Conventions Center provides the following information on the
updates to the IERS Conventions since IERS Message No. 142 (February 16,
2008).

Chapter 4 "Terrestrial reference systems and frames" has been updated on
10 April 2009, see http://tai.bipm.org/iers/convupdt/convupdt_c4.html .
The chapter (with a new title) has been significantly rewritten with
Z. Altamimi and C. Boucher as the main authors. A presentation of
ITRF2005 is now included. 

Chapter 7 "Displacements of reference points" has been updated on
10 April 2009, see http://tai.bipm.org/iers/convupdt/convupdt_c7.html .
The subroutine dehanttideinel.f has been updated to correct for a bug
(thanks to T. Springer). The effect of this bug was < 0.05 mm.

The Conventions Center is starting to upgrade the Conventions software
in order to provide additional documentation. At the same time, a new
software license is being added, providing information regarding the
terms and conditions for use of the Conventions software. It is
anticipated that upgraded routines will be available by the time of the
IAU General Assembly.

Gerard Petit and Brian Luzum
IERS Conventions Center


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