****************************************************************************** DORISMail 31-Oct-2002 13:27:14 Message No 0205 ****************************************************************************** Author: "H. Fagard" Subject: Unlucky new station at Thule (Greenland) Dear Colleagues, A new DORIS station has been installed within the premises of the US Air Force base at Thule, Greenland, Denmark, thanks to the kind contribution of the Danish national survey agency, KMS. It consists of a third generation beacon installed in the same shelter that hosts the GPS receivers of the IGS stations THU1 and THU3. The Starec antenna is installed on top of a 2 m high, 30 cm sided very rigid tower, set on a large concrete pad (21 m x 9 m, 0.3 m thick), founded 1.7 m deep in the permafrost. The name of the station is "Thule" and its acronym in the data files is THUB. Transmissions started on September 28. The DOMES number for the antenna reference point is 43001S005. Its approximate coordinates (ITRF2000, 1997.0) are: X= 538110.68 m Y= -1389031.33 m Z= 6180994.48 (sigma: 1 cm) The ITRF2000 velocities for the nearby "THU1" IGS station are: VX = -0.0217 m/y VY = -0.0041 m/y VZ = 0.0033 m/y Unfortunately, this new station (the 55th in our network) has not stood the test of the harsh Arctic climate. Although the tower and fastening bolts we use are designed to stand stronger winds that the 100 knot storm that blew on October 14, they did not resist a crash from a nearby hut (6 meter long) and the large concrete beams that were supposed to keep this hut in place, that were moved by several meters by the wind. Our tower (which stopped the hut's movement) was bent and the DORIS antenna broken at a 45 degree angle. Transmissions were not stopped immediately (I don't have the exact date, but this should have been done between October 16 and 18) therefore I recommend to the analysis centers to discard any data from THUB dated October 14 or later. A spare tower and antenna are on their way to Thule, and I will keep you posted on the status of this station. 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 ====================================================================== [ Part 2: "Attached Text" ] Please do not reply directly to this message, but send comments and suggestions to IDS.central.bureau@cls.fr