[IGSMAIL-5661]: recent updates to the IERS Conventions

[Jim.Ray]

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IGS Electronic Mail      21 Nov 06:09:55 PST 2007      Message Number 5661
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Author: Jim Ray (Conventions Advisory Board)

Gerard Petit and Brian Luzum of the IERS Conventions
Center have announced the following updates in IERS
Message No. 121.

*  Chapter 9 "Troposheric model" was extensively revised
on 28 June 2007, as previously reported.  See
  http://tai.bipm.org/iers/convupdt/convupdt_c9.html

* Chapter 5 "Transformation Celestial and Terrestrial
Systems" was updated on

   + 16 February 2007: Revised section 5.8.3 to make the
     references for the planetary fundamental arguments
     clear (from P. Wallace and N. Capitaine).

   + 23 October 2007: New section 5.4.6 on Free Core
     Nutation (FCN) has been added with a subroutine for
     a discrete model by S. Lambert, for those who do
     not apply IERS published empirical nutation offsets.
     Additional minor corrections in the text make the
     chapter's terminology consistent with current IAU
     Recommendations.

See: http://tai.bipm.org/iers/convupdt/convupdt_c5.html

* Chapter 7 "Displacement of Reference Points" was updated
on 20 June 2007 and 23 October 2007 for minor corrections
in the solid Earth tides subroutine dehanttideinel.f for
effects at the level of 0.1 mm or less.  The routine
remains under review for some other possible corrections
whose effect should be <0.05 mm.  See:
  http://tai.bipm.org/iers/convupdt/convupdt_c7.html


Information on all IERS Conventions updates can be found
at:  http://tai.bipm.org/iers/convupdt/convupdt.html