Ron
November 19th 04, 08:47 PM
http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36102
Preparations for Trajectory Correction Manoeuvre 4
European Space Agency
Rosetta
November 19, 2004
Report for 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 manoeuver have been loaded
on-board. This small Trajectory Correction Manoeuver 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:
Mission Date DOY Main Activity
Day
241 28/29.10.04 302 Monitoring pass
248 04/05.11.04 309 Monitoring pass - Gyro-less estimator switch-on
255 11/12.11.04 316 Monitoring pass
262 18/19.11.04 323 Monitoring pass - TCM-4 Preparation
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.
Preparations for Trajectory Correction Manoeuvre 4
European Space Agency
Rosetta
November 19, 2004
Report for 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 manoeuver have been loaded
on-board. This small Trajectory Correction Manoeuver 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:
Mission Date DOY Main Activity
Day
241 28/29.10.04 302 Monitoring pass
248 04/05.11.04 309 Monitoring pass - Gyro-less estimator switch-on
255 11/12.11.04 316 Monitoring pass
262 18/19.11.04 323 Monitoring pass - TCM-4 Preparation
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.