News

28.03.2013 09:53 Age: 12 yrs

[Jason-2] Jason-2 status update - start of recovery

Category: Operational news

The Jason-2 spacecraft entered safe mode on 25 March 2013 at approximately 03:30:59z. The current schedule foresee to turn on the Jason-2 payload core science instruments (POSEIDON3, AMR, GPSP) on Saturday, 30 March.

The Jason-2 spacecraft entered safe mode on 25 March 2013 at approximately 03:30:59z.
 
Jason-2 went to safe hold mode (SHM) during an Usingen pass, five minutes after a READMM telecommand. No on board alarms can be seen in the telemetry. The SHM caused an automatic switch to the redundant payload module (PM-B). Then Jason-2 converged to nominal 'BBQ' mode.
 
As the mission was running since the beginning on PM-A (allowing PM-B to be a full platform redundancy), CNES decided to switch back to PM-A in order to verify its status. During the autotest, one error inside the onboard memory was identified; after investigation this memory error was declared non critical and also not related to the previous SHM. To date diagnostics of the spacecraft by CNES and Thales Alenia Space (TAS) did not detect any trouble in the sub-systems or any loss of redundancy. Thus decision to remain on PM-A and to give priority to the recovery was approved.
 
The requested platform recovery operations for resuming the nominal mission have started on Tuesday 26th and are now well underway with gyros, star trackers and reaction wheels switched ON the 27th. DORIS instrument is operational since 26 March 02:20z. The OPS teams from CNES and NOAA are working closely to conduct operations and to monitor the spacecraft carefully. Due to orbital configuration most of recovery operations are performed during the european night!
 
The current schedule foresee to turn on the Jason-2 payload core science instruments (POSEIDON3, AMR, GPSP) on Saturday, 30 March, and full science operations will resume later that day. Jason-2 passengers (LPT, CARMEN2, T2L2) will be turned on on Tuesday, 2 April.
Of course this schedule is optimistic… there is no margin and it does not take into account any unexpected event.
The Jason-2 mission was interrupted during Cycle 174.  Cycle 174 will be impacted approximatively from passes 43 to 168. Normal science operations will resume prior to Cycle 175, which begins on 02 April at 09:03 UT.
 
 
Very best regards,
 
Thierry Guinle - CNES
on behalf EUMETSAT-NOAA-CNES-JPL Project Managers