Subject: [SLR-Mail] No. 1730: Termination of the mission for GFO-1 From: Frank Lemoine ******************************************************************************** SLR Electronic Mail 2008-11-09 12:35:00 UTC Message No. 1730 ******************************************************************************** Author: Frank Lemoine Subject: Termination of the mission for GFO-1 Dear Colleagues- On about September 25, 2008, the GFO-1 went into safe mode, and into a non-nadir pointing attitude. The spacecraft team has attempted to recover the satellite, but the aged condition of the batteries and other spacecraft systems have made the recovery and return to normal operations impossible. Thus the decision has been taken to terminate the mission. The spacecraft will be guided into a re-entry, burning up its remaining fuel to prevent it from becoming a derelict and a space debris hazard. A maneuver is scheduled this weekend. We have been asked to support orbit determination up to and immediately following the maneuver to verify OD. We request the ILRS stations remove GFO from the tracking roster as of Wednesday November 12, 2008 the end of the UT day. The GFO project, and the scientific users of the GFO altimeter data (at NOAA, NASA, AVISO, and many other institutions) are extremely grateful for the contribution of the ILRS network over the past ten years. The mission was on the verge of cancellation after the failure of the GPS receiver, when the ILRS demonstrated that SLR tracking could be used to provided daily operational orbits. This was only possible because of the close interaction between the POD (Precision Orbit Determination) team at GSFC, the ILRS, and NOAA who prepared the daily altimeter data IGDRs (Interim Geophysical Data Records). As a result, we have compiled an eight-year dataset of satellite altimetry that augments the data provide by other missions (TOPEX, Jason-1, ENVISAT, Jason-2) for synoptic observation of the oceans. The GFO scientific users thank the ILRS for its dedication and support over the last ten years. Sincerely, Frank Lemoine Code 698, Planetary Geodynamics Laboratory From: slrmail@dgfi3.dgfi.badw-muenchen.de ********************************************************************************