Message-ID: <068CC65B1509FA4D89CB2E7509C5E7B97FB97A@cluwsh03.gold.rtgold.nima.mil> From: "Slater, James A. " To: "'igsmail@igscb.jpl.nasa.gov'" Subject: [IGSMAIL-4219]: 3 New GLONASS Satellites Launched Date: Thu, 26 Dec 2002 14:34:04 -0500 Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 26 Dec 11:34:33 PST 2002 Message Number 4219 ****************************************************************************** Author: Jim Slater Season's Greetings from IGLOS!!! (Some of you will have already seen this message from IGLOSmail, so I apologize for the duplication. Jim Ray also sent an IGSmail message with the GLONASS launch news.) On 25 December 2002, three new GLONASS satellites were launched into slots 21, 22 and 23 in orbit plane 3. These are designated as GLONASS numbers 792, 791 and 793, respectively. If they are all successfully placed into operation, there will be 10 operational GLONASS satellites. The IGS's IGLOS tracking network now consists of about 45 worldwide tracking stations with dual-frequency receivers. These data are integrated into the IGS Global Data Center archives. BKG and ESA in Germany and the Mission Control Center in Russia continue to compute precise orbits for all the satellites. These individual orbits are combined by the IGLOS Analysis Coordinator to produce combined orbits for each GLONASS satellite. (We are still looking for one or more additional analysis centers to compute GLONASS orbits in order to strengthen the quality of the combined orbits.) We have noticed that many organizations have been downloading the precise orbits. We would very much like to know what the orbits and tracking data are being used for. PLEASE SEND ME INFORMATION ABOUT WHAT APPLICATIONS AND USES YOU HAVE FOR THE GLONASS DATA AND ORBITS. There is a considerable amount of effort being made by all the organizations that run the tracking stations, and by the Analysis Centers and other individuals to maintain the IGLOS project. The IGS needs to understand what people are using these data for and whether it is worthwhile to maintain the GLONASS service. We will be evaluating this during the next few months. The 10-satellite GLONASS constellation when added to the GPS constellation of 28 satellites means that the user community will have 38 navigation satellites available. The extra satellites can provide positional accuracy benefits in areas with obstructed visibility at lower elevation angles. They can also add a significant amount of data for certain ionospheric and atmospheric applications that currently exploit the microwave signals from GPS. Integration of GLONASS and GPS data into existing software and applications has been a good test case for the interoperability and compatibility issues that will be encountered when trying to do the same thing with the European Galileo system in the future. Best Wishes for the coming year! Jim Slater, Chair IGLOS Pilot Project ............................................................................ ................ JIM SLATER (301)227-4549 Fax: (301)227-2837 E-mail: slaterj@nima.mil NIMA, PPSC, MS D-68, 4600 Sangamore Rd., Bethesda, MD 20816-5003, U.S.A. "...skate to where the puck is going to be, not where it has been." -Wayne Gretzky