****************************************************************************** dorismail 24-Feb-2020 16:32:04 Message No 1220 ****************************************************************************** Author: Ferrage Pascale Subject: [Jason-3] Doris data interruption due to Safe Hold Mode Dear colleagues, Jason3 was twice in Safe Hold Mode between 2020/01/31 to 2020/02/12 During this period, the impacts on the dissemination of DORIS data to the IDS Data Centers (IGN/CDDIS) were as follows: Between 2020/01/31 at 4:51 TU to 2020/02/04 at 15:59 TU and between 2020/02/05 at 21:00 TU to 2020/02/12 at 17:05 TU: NO available/valid DORIS data & products : DORIS data (RINEX format), orbits (sp3 format) , solar panel & attitude quaternions files Best regards, Pascale Ferrage De : Marechal Christophe Envoy=E9 : jeudi 6 f=E9vrier 2020 16:49 =C0 : ostst@jpl.nasa.gov Cc : aviso@altimetry.fr Objet : [EXTERNAL] [Jason-3] New Safe Hold Mode Dear OSTST, Yesterday, on February 5th, at 21:00:53UTC (cycle 147, pass 45) , a new Saf= e Hold Mode was triggered on Jason-3, immediately stopping its measurements. Despite the fact that this new SHM occurs only 12 hours after recovery, the= re is no sign of degradation of the gyros. The symptoms of this new SHM (no reconfiguration telemetry available) are s= imilar to what happened in April 2019. At that time, investigations conclud= ed to a RAM corruption. A recovery was performed, with no new occurrence un= til now. In order to ensure full reliability of the satellite, extensive tests will = be run on the RAM in the coming days. SHM recovery operations are then slig= htly delayed, and may start at the beginning of next week. We will of course keep you updated of Jason-3 status. Very best regards, Christophe Marechal / CNES JASON-3 project manager, on behalf 4P project ma= nagers, at EUMETSAT, NOAA, and JPL. ___________________________________________________________________________= __________ De : Marechal Christophe Envoy=E9 : jeudi 6 f=E9vrier 2020 16:49 =C0 : ostst@jpl.nasa.gov Cc : aviso@altimetry.fr Objet : [EXTERNAL] [Jason-3] New Safe Hold Mode Dear OSTST, Yesterday, on February 5th, at 21:00:53UTC (cycle 147, pass 45) , a new Saf= e Hold Mode was triggered on Jason-3, immediately stopping its measurements. Despite the fact that this new SHM occurs only 12 hours after recovery, the= re is no sign of degradation of the gyros. The symptoms of this new SHM (no reconfiguration telemetry available) are s= imilar to what happened in April 2019. At that time, investigations conclud= ed to a RAM corruption. A recovery was performed, with no new occurrence un= til now. In order to ensure full reliability of the satellite, extensive tests will = be run on the RAM in the coming days. SHM recovery operations are then slig= htly delayed, and may start at the beginning of next week. We will of course keep you updated of Jason-3 status. Very best regards, Christophe Marechal / CNES JASON-3 project manager, on behalf 4P project ma= nagers, at EUMETSAT, NOAA, and JPL. De : Marechal Christophe Envoy=E9 : mercredi 5 f=E9vrier 2020 10:59 =C0 : Marechal Christophe ; ostst@jpl.nasa.gov Cc : aviso@altimetry.fr Objet : [EXTERNAL] Jason-3 back to operations Dear OSTST, Jason-3 was restarted successfully on the last visibility (cycle 147 pass 3= 3) : - POSEIDON at 09:34UTC - AMR at 09:36UTC - GPSP at 09:37UTC OGDRs will start flowing around 11:45UTC. Very best regards, Christophe Marechal / CNES JASON-3 project manager, on behalf 4P project ma= nagers, at EUMETSAT, NOAA, and JPL. __________________________________________________________________________ De : Marechal Christophe Envoy=E9 : vendredi 31 janvier 2020 16:59 =C0 : ostst@jpl.nasa.gov Cc : aviso@altimetry.fr Objet : [EXTERNAL] Jason-3 in Safe Hold Mode on January 31st, 2020 Dear OSTST, Today, January 31st 2020, at 04:51:17 UTC, during pass 154 of cycle 146, Ja= son-3 was automatically reconfigured to Safe Hold Mode, immediately interru= pting its measurements. This event was triggered by an anomaly in SAA of its gyro #3. Our first ana= lyses show that the symptoms of this anomaly are not consistent with the se= veral anomalies met between 2017 and 2019 on Jason-2 gyros. It has then bee= n decided to carry on nominally with a Safe Hold Mode recovery procedure, a= nd restart the gyros nominally next Monday. The operational team is working hard on this recovery, and hopes to restart= Jason-3 measurements during next week : the time for restart will be commu= nicated beginning of next week, as soon as it is precisely known. Very best regards, Christophe Marechal / CNES JASON-3 project manager, on behalf 4P project ma= nagers, at EUMETSAT, NOAA, and JPL.