MOC data transfer and storage

(Note: Adapted from Tauber et al. 2010, A&A 520, A1 & private communication from S. Foley)

The mission operations centre (MOC), located at ESA’s operations centre in Darmstadt (Germany), is responsible for all aspects of flight control and of the health and safety of the Planck satellite, including both instruments. It plans and executes all necessary satellite activities, including instrument commanding requests by the instrument operations centres. MOC communicates with the satellite using two ESA deep-space ground stations in New Norcia (Australia) and Cebreros (Spain), usually the former, over a daily 3-h period, during which it uplinks a scheduled activity timeline which is autonomously executed by the satellite, and downlinks the science and housekeeping (HK) data acquired by the satellite during the past 24 h. The downlinked data are transferred from the ground station to the MOC over a period of typically 8 h; at MOC they are put onto a data server from where they are retrieved by the two Data Processing Centres.

There is no data processing done at MOC. Only transfer and storage of data is performed at this stage. MOC verifies the reception of all telemetry packets, which are transfered from the spacecraft via the ground station, as given by the Source Sequence Count related to each Virtual Channel (VC) and Application ID (APID). All data are stored in the Long Term Archive (LTA) as telemetry packets (duplicated in A and B archives). The LTAs present an archive of all data, both science and house-keeping, acquired through the whole mission.