[IGSMAIL-6127]: updated IERS Conventions Chapters 1 and 3

[Gérard Petit]

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IGS Electronic Mail      09 Apr 10:03:53 PDT 2010      Message Number 6127
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Author: Girard Petit (IERS Conventions Center)


Information on the updates to the IERS Conventions

The IERS Conventions Center informs of the following updates:

Chapter 1 "General definitions and numerical standards" has been updated on
9 April 2010, see http://tai.bipm.org/iers/convupdt/convupdt_c1.html.
[Note that an interim version was present on 8 April 2010,
please update if you happen to have taken it]

The section "Numerical standards" has been re-written and the list
of constants ensures consistency with the IAU (2009) system of
astronomical constants.


Chapter 3 "Conventional Dynamical Realization of the ICRS" has been updated
on
8 April 2010, see http://tai.bipm.org/iers/convupdt/convupdt_c3.html.

The chapter has been re-written (with W.M. Folkner as main contributor)
and provides information on recently released ephemerides.
When a conventional choice is needed, DE421 is recommended to provide
continuity for implementation by users.

Girard Petit and Brian Luzum
IERS Conventions Center


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Gerard Petit
Time, frequency and gravimetry department, BIPM
Address: Pavillon de Breteuil
         92312 Sevres  FRANCE
Phone: (33)1-45077067
FAX: (33)1-45077059
E-mail: gpetit at bipm.org