****************************************************************************** DORISMail 28-Sep-2004 16:18:24 Message No 0348 ****************************************************************************** Author: "H. Fagard" Subject: Antenna change at Marion Island (South Africa) Dear Colleagues, The DORIS antenna at Marion Island (South of South Africa) and its support have been changed. The old antenna drift (see DORISMail #335), due to corrosion of the aluminum plate, was measured and found equal to 67 mm towards North (for the 2 GHz phase center). The new Starec antenna is supported by a two meter very rigid metal tower, bolted on the same one-meter sided concrete block as the former antenna support. The beacon is a 3.0 model which was installed in April 2003. Transmissions from the former antenna (MARB) stopped on August 15, and resumed from the new antenna on August 21. The acronym for the new reference point is MATB. The DOMES number for the new antenna reference point is 30313S003. Its coordinates (ITRF2000, 1997.0) are: X = 3448405.705 m Y = 2680356.397 m Z = -4632640.602 m (sigma: 1 cm) The ITRF2000 velocities for this site (derived from MARA) are: VX = -0.0053 m/y VY = 0.0027 m/y VZ = 0.0020 m/y Many thanks to Attie Combrinck, a surveyor from the HartRAO (Hartebeesthoek Radio Astronomical Observatory) for successfully carrying out this renovation. Best regards, Herve Fagard -- ====================================================================== Herve FAGARD e-mail : herve.fagard@ign.fr Institut Geographique National 94165 SAINT-MANDE CEDEX PHONE : + 33 1 43 98 81 48 FRANCE FAX : + 33 1 43 98 84 50 ====================================================================== Please do not reply directly to this message, but send comments and suggestions to IDS.central.bureau@cls.fr