ESA Science & Technology - No. 23 - Monitoring New Avionics Software

Taking the opportunity of this period of daily contact a number of tests were carried out, which in turn served as confidence checks of the functionality of the new software:

• the two Navigation Cameras were checked out on 25 July and the first pictures received showed the Earth-Moon system from a distance of 70 million km
• for the first time the new strategy for reaction wheel offloading in an optimized attitude was used on 27 July, to reduce fuel consumption in high disturbance torques conditions
• the redundant Transfer Frame Generator (TFG) and Decoder were tested as part of the redundancy commissioning
• a special Star Tracker test was carried out on 29 July to track stars which have been identified for elimination from the catalogue
• a new thermal characterization exercise was carried out on 29 July, to observe the thermal behaviour of the spacecraft when the Sun is shining on the -Z side with an inclination of 50 degrees over the +X axis

The TC files containing the patch commands for the redundant avionics processors have been uplinked to the on-board mass memory. The patch of the redundant processors to the new software version 7 is planned for the beginning of August.

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

At the end of the last New Norcia pass in the reporting period (DOY 212) Rosetta was at 71.9 million kilometres from the Earth. The one-way signal travel time was 3 minutes 59 seconds.