| Date: | 2006-11-04 00:25:00 | |
| Sender: | F. Lemoine <Frank G. Lemoine <flemoine@puuoo.gsfc.nasa.gov>> | |
| Subject: | [SLR-Mail] No. 1503: Jason-1 spacecraft in safehold | |
| Author: | F. Lemoine | |
| Content: | ******************************************************************************** SLR Electronic Mail 2006-11-04 00:25:00 UTC Message No. 1503 ******************************************************************************** Author: F. Lemoine Subject: Jason-1 spacecraft in safehold Dear Colleagues, This message is sent by SLRMAIL, because of exploder problems at the CDDIS. The Jason-1 spacecraft has been in safehold since October 30. As per the project status message below, corrective measures are being taken by the CNES and JPL control centers. In safehold, the spacecraft is not in its nominal attitude, so this explains the tracking problems experienced by SLR stations in recent days. We will send out updates as soon as more information becomes available. In the meantime, normal tracking of Jason-1 may be reduced although we need some passes to maintain the SLR predicts, and to avoid the need to resort to use of TLE´s when Jason-1 exits safehold. Sincerely, F.G. Lemoine NASA Goddard Space Flight Center ====================================================================== DATE: 30 October 2006, 1700 PDT PROJECT: Jason-1 DATE OF INCIDENT: 30 October 2006 LOCATION OF INCIDENT: In Earth Orbit DESCRIPTION OF INCIDENT: On a routine Jason-1 telemetry contact through the CNES Aussaguel (France) Earth Terminal on October 30 at 1326 PDT, numerous ground system telemetry alarms indicated that the satellite had transitioned to a Safe Mode state. CORRECTIVE ACTION: Per documented Safe Mode contingency procedures, commands were uplinked to command the satellite to a low-rate telemetry mode; it was also verified that the satellite was in a safe and power-positive sun-pointing configuration. Over several subsequent contact opportunities, attempts were made to read out recorded on-board engineering telemetry data in proximity to the Safe Mode transition point; however, early indications are these data were somehow corrupted in the on-board memory storage unit, and useful data around the anomaly event may not be present/available (it is possible this corruption may be a symptom or cause of the Safe Mode transition). IMPACT ON PROJECT AND SCHEDULE: No science data is being collected while the satellite is in a Safe Mode configuration, and the satellite currently remains in a stable, power-positive state. CNES is now managing and directing satellite contingency operations from the CNES operations center in Toulouse, France, with support from the JPL operations center. Additional incident report updates will be issued when the cause of the anomaly has been determined and a recovery plan/schedule is made available. From: ”Frank G. Lemoine” ******************************************************************************** |