No. 43 - Reload of SSMM Onboard Software
This software was required to cure a problem detected before launch affecting the selective dump of compressed files. The new software had already been delivered by SAAB in October 2004, but the activity was postponed to June 2005 due to the criticality of the operations involved. The spacecraft was configured to operate without SSMM over several days, whilst the actual software upload took place on 7 and 8 June. All activities were carried out successfully and in fact completed one day earlier than planned. On 9 June Rosetta was back to its nominal configuration with full use of the SSMM capabilities.
On 31 May a test of the OSIRIS door mechanism was carried out with the presence of the PI team at ESOC. The purpose of this test was to characterise the behaviour of the flight model, compare it with the test results on the ground models and finalise the new software routines for the control of the door to be uplinked on 14 June. The test was successful and the OSIRIS team has already delivered the new software. ESOC is preparing for next week's uplink and verification operations.
On 1 June a new version of the On-Board Control Procedure (OBCP) that controls the RPC (Rosetta Plasma Consortium) modes was uplinked. The procedure was verified by switching on the RPC and the Langmuir Probe instrument (LAP) - one of the five instruments comprising the RPC.
SREM is always active in the background, but the instrument was temporarily deactivated over the period of SSMM software maintenance.
A total of 6 New Norcia passes of a max duration of about 9 hours commanding were taken over the reporting period (three passes per week).
|OSIRIS Door test
|Uplink and verify updated RPC OBCP
|Prepare SSMM OBSM; go to short Mission Timeline (MTL)
|Go to ops without SSMM, and SSMM OBSM on Memory Controller B (MC B)
|SSMM OBSM on MC A
|Go to Normal MTL + uplink OSIRIS OBSM files
At the end of the reporting period (DOY 161) Rosetta was at 46.5 million kilometres from the Earth. The one-way signal travel time was 2 minutes and 34.9 seconds.