| Date: | 2010-06-17 23:42:00 | |
| Sender: | Rolf Koenig/GFZ <Carey Noll <Carey.Noll@nasa.gov>> | |
| Subject: | [SLR-Mail] No. 1876: Upcoming launch of TanDEM-X | |
| Author: | Rolf Koenig | |
| Content: | ******************************************************************************** SLR Electronic Mail 2010-06-17 23:42:00 UTC Message No. 1876 ******************************************************************************** Author: Rolf Koenig/GFZ Subject: Upcoming launch of TanDEM-X Dear Colleagues: Launch of TanDEM-X (TDX) is planned for June 21, 2010, 02:24 UTC, from Baikonur launch site. Initial orbit predictions can be found in the operational directories at CDDIS and EDC for CPF predictions, e.g.: ftp://cddis.gsfc.nasa.gov/pub/slr/cpf_predicts/2010/tandemx/tandemx_cpf_100621_6725.gfz The SIC number for TDX is 6202; the ILRS name is ”tandemx”; the COSPAR ID and NORAD number will be sent out as soon as they have been identified. The normal point bin size for TDX should be set to 5 s in accordance with the TSX settings. Tracking can start any time; however the satellite will be subject to a series of checkouts that mainly concern the attitude of the spacecraft. Stations are free to try as soon as the predictions are issued. We´ll update the orbit predictions any time we get better orbit knowledge and new maneuver planning information: so stay tuned during the first few days. The commissioning phase of TanDEM-X and its formation flight with TerraSAR-X (TSX) seen from the orbit point of view will look as follows: 2010-06-21 - 2010-07-21: Launch and early orbit phase (LEOP): TDX will drift towards TSX until 20 km along-track distance is reached prior to the end of this phase. 2010-07-22 - 2010-10-03: Mono-static commissioning phase: 20 km along- track distance will be maintained: maximum cross-track distance between the orbits at the equator will be 1305 m, the estimated radial distance between orbits will be 300 m at the poles and 0 m at the equator. 2010-10-04 - 2010-10-06: Transition to close formation. 2010-10-07 - 2010-10-17: Maintenance for ground segment checkout and updates: close formation. 2010-10-18 - 2010-11-30: Bi-static commissioning phase: close formation; the mean along-track distance between the satellites will be 0, the maximum across-track separation at the equator will be 362 m and the radial distances will be 400 m at the poles and 0 m at the equator. The SLR tracking challenges of the close formation were reported at the Laser Workshop in Poznan by Snopek, Grunwaldt and Koenig: ”Challenges of the TerraSAR/TanDEM-X formation”. In summary: Satellite separation will be between 300 and 600 m; the orbits will form a helix so separation occurs in all directions, radial, cross-and along-track. Orbit predictions should be much better than the minimum separation between the satellites, which should help in distinguishing between the targets. Common field of view for both targets will occur in approximately 20 % of all possible tracks (at low elevations). Under these conditions, the distance in range between the two targets should be larger than 2000 ns most of the time, which again should allow distinction between the two targets. The stations are advised to interleave the passes of TSX and TDX if they can, otherwise they should track alternate passes. If you have any questions, please contact Rolf Koenig at: -------------------------------------------- Dr. Rolf Koenig Dep. 1: Geodesy and Remote Sensing Phone: +49 (0)8153/28-1353 FAX: +49 (0)8153/28-1735 Email: rolf.koenig@gfz-potsdam.de --------------------------------- Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Public Law Foundation State of Brandenburg c/o DLR Oberpfaffenhofen, 82234 Wessling -------------------------------------------- Regards, Carey. ----- Ms. Carey Noll Manager, Crustal Dynamics Data Information System (CDDIS) Secretary, ILRS Central Bureau NASA GSFC Code 690.1 Greenbelt, MD 20771 USA E-mail: Carey.Noll@nasa.gov Voice: (301) 614-6542 Fax: (301) 614-6015 WWW: http://cddis.gsfc.nasa.gov From: Carey Noll ******************************************************************************** |