Reply-To: From: =?iso-8859-1?Q?G=E9rard_Petit?= To: , , , Cc: Subject: [IGSMAIL-6127]: updated IERS Conventions Chapters 1 and 3 Date: Fri, 9 Apr 2010 18:54:21 +0200 Organization: BIPM Message-ID: Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Thread-Index: AcrP7/L0qOVdvSH9Q4ukGQa/iIqi6QIA65AA Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 09 Apr 10:03:53 PDT 2010 Message Number 6127 ****************************************************************************** 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 ---------------------------------------- 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@bipm.org