No. 61 - Operational Updates
No payload operations were carried out in the reporting period. SREM was kept active in the background for the entire period, and configured for a lower data collection rate to cope with the reduced visibility periods and bitrates available during the passive cruise period.
During the reporting period, the Rosetta Mission Control System was migrated to a new version based on the Venus Express system. The system was successfully used operationally for the first time on 14 June.
A total of 4 New Norcia passes of 8 hours commanding were taken during the reporting period.
TM/TC links with the OCC have been established for all passes. In addition, 2 Cebreros passes were scheduled on 6 and 7 June for investigation of noise on the coherent downlink signal.
|830||07.06.06||158||NSHM monitor pass|
|837||14.06.06||165||NSHM monitor pass|
|844||21.06.06||172||NSHM monitor pass - TM bit rate to 223 bps and Solar Array repositioning|
|851||28.06.06||179||NSHM monitor pass|
At the end of the reporting period (DOY 181) Rosetta was at 330.3 million kilometres from Earth (2.21 AU; one-way signal travel time was 17 minutes 41 seconds). The distance to the Sun was 192.4 million kilometres (1.28 AU).
As expected after Near Sun Hibernation Mode entry, the temperature of the spacecraft internal units, such as batteries, tanks, CDMUs, reaction wheels, has decreased by a few degrees. Apart from this mode-related adjustment of the on-board temperatures, the spacecraft is slowly warming up as the Sun distance decreases.
The only instrument operated in the reporting period was SREM. SREM remains active in the background for radiation monitoring, with reduced accumulation parameters (since DOY 142/2006) to cope with the limited ground contacts during the near Sun hibernation period.
The spacecraft will remain in Passive Cruise Mode until 26 July 2006. During the entire period, the spacecraft will be monitored on the basis of weekly ground station passes.
Operations for the Mars swing-by (February 2007) will start in August 2006, with another payload passive checkout (PC3), an intense tracking campaign around the Trajectory Correction Manoeuvre (DSM-2) in September, and the first payload Active Checkout (PC4) in November/December.