Rosetta Status Report 26 April 2004

Second ALICE Commissioning Slot

Report for week 16 to 23 April 2004

Payload commissioning activities continued in the reporting period. The main activity was the completion of the second ALICE commissioning slot. In support of the ALICE high voltage operations the ROSINA COPS pressure monitor was active for most of the time.

All activities were successfully executed, but some delays were accumulated due to the fact that the prime pyro firing to open the ALICE detector door did not work (DOY 108) and an investigation was conducted before the redundant pyro could be fired. This activity took place successfully on DOY 112 and the detector door confirmed open. As a result of the delay, the final ALICE Payload Aliveness Test, originally scheduled for this slot, was postponed to DOY 115. This does not have any impact on the rest of the commissioning schedule since the pass on DOY 115 was scheduled to be a passive telemetry dump pass.

On the subsystem side no special activity was performed. Close monitoring of the thermal environment continues, but the temperatures were very stable throughout the week, including in the new inertial pointing attitude required by ALICE.

The table below shows a chronology of the main activities in the reporting period:

Mission Day	Date	DOY	Main Activity
46	16/17.04.04	107/108	ALICE commissioning slot 2 – pass 2
47	17/18.04.04	108/109	ALICE commissioning slot 2 – pass 3
48	18/19.04.04	109/110	ALICE commissioning slot 2 – pass 4
49	19/20.04.04	110/111	ALICE commissioning slot 2 – pass 5
50	20/21.04.04	111/112	ALICE commissioning slot 2 – pass 6
51	21/22.04.04	112/113	ALICE commissioning slot 2 – pass 7
52	22/23.04.04	113/114	ALICE commissioning slot 2 – pass 8

At the end of the last New Norcia pass in the reporting period (DOY 114, 02:40) Rosetta was at 20 million km from the Earth. The one-way signal travel time was 66 seconds.