No. 71 - First Payload Active Checkout Operations
15 Dec 2006 16:34Report for Period 8 December to 15 December 2006
The reporting period covers the third consecutive week of active checkout operations with the Rosetta payload. During this period, the operated instruments included ALICE, OSIRIS, ROSINA, VIRTIS, RPC and SREM. In particular, interactive checkout operations were performed with OSIRIS and ROSINA. RPC and SREM remain active in the background throughout the campaign. The other instruments are only activated for execution of their checkout sequences.
All checkout operations were executed smoothly, except for the OSIRIS non-interactive operations scheduled for out-of-ground-coverage execution between 9 and 11 December, which failed because of an instrument anomaly.
The instrument was switched-off by ground as soon as the anomaly was detected during the ground contact on 11 December. A basic health confidence check with OSIRIS, to confirm that the anomaly has not impacted the instrument safety, is being scheduled on 20/21 December.
A total of 5 New Norcia (NNO) passes of 9 to 12 hours commanding were taken during the reporting period. One tracking pass of 4 hours and one delta-DOR measurement have been taken with DSN.
At the end of the reporting period (DOY 349) Rosetta was at 303.9 million km from Earth (2.03 AU; one-way signal travel time was 16 minutes 14 seconds). The distance to the Sun was 172 million km (1.15 AU).
The third PC4 non-interactive block was carried out outside ground station coverage and involved ALICE, OSIRIS, VIRTIS, RPC and SREM. The data acquired during this block were retrieved on ground on DOY 345 and completed as expected during the same pass. The OSIRIS observations failed due to an instrument anomaly that occurred at the beginning of the slot. All other instrument operations were successful. SREM and RPC remain active continuously throughout the Active Checkout scenario, with the exception of occasional RPC switch-off when required by other instruments.
The Mars Swingby Phase formally started on 28 July. The actual swingby will take place on 25 February 2007, followed by a Deep Space Manoeuvre in April 2007.
The on-going Payload Active Checkout (PC4) will last four weeks, with the last operations scheduled to be completed on 22 December.
The next short-term activities include a thermal characterisation on 27 December, an observation of asteroid Lutetia by OSIRIS between 2 and 4 January 2007, and a test of the pre-eclipse Mars observation attitude on 7 January.