No. 43 - Reload of SSMM Onboard Software
14 June 2005 08:52Report for period 27 May to 10 June 2005
The Rosetta spacecraft is in active cruise mode in preparation for the next science phase planned for end June. The most important activity in the reporting period was a full reload of the Solid State Mass Memory (SSMM) onboard software, carried out in the period 7 to 9 June.
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).
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.