No. 34 - Preparations for Trajectory Correction Manoeuvre 4
19 November 2004 16:37Report for the period 28 October to 19 November 2004
Rosetta continues to fly in cruise mode which it entered 17 October. The AOCS gyro-less estimator was activated on 4 November and has been running since, outside the control loop for validation. This activity required an AOCMS patch in RAM to prevent incorrect use of gyro-less estimator output by the FDIR when the gyro-less and gyro-stellar estimators are ON in parallel. So far, the performance of the gyro-less estimator is good.
The last pass of the reporting period was dedicated to the preparation of TCM-4. In particular, the slews around the manoeuvre have been loaded on-board. This small Trajectory Correction Manoeuvre of about 9 cms-1 is planned on 25 November. SREM is kept activated for background radiation monitoring since 22 October. Weekly passes over the New Norcia station have been made since 18 October. There is no DSN support during this phase.
The table below shows a chronology of the main activities in the reporting period:
Note: skipped passes are not included.
At the end of the last New Norcia pass in the reporting period (DOY 324) Rosetta was at 49.8 million kilometres from the Earth. The one-way signal travel time was 2 minutes 46 seconds.