Operations and data
The Swarm mission is operated by ESA’s European Space Operations Centre, ESOC, in Germany, via the primary ground station in Kiruna, Sweden.
The critical launch and early orbit phase lasts about three days, during which the satellites’ booms are deployed and all the satellite units are switched on. This is followed by a three-month commissioning phase to ensure all the instruments are working correctly. To increase the number of daily contacts with the satellites during this phase, complementary ground stations in Norway, Antarctica and Australia are also used.
Once commissioned, Kiruna remains the primary ground station, both for receiving science data and for uplinking operational commands from ESOC. Data are downlinked from each satellite once a day.
The science data are then transferred to the Payload Data Ground Segment, PDGS, in Farnborough, UK. The PDGS is responsible for data processing, data archiving and user services.
The first step is to time-order and reformat the data to ‘Level-0’. These are then calibrated and processed to form ‘Level-1’data products, which are disseminated to the Swarm user community. ESA’s Centre for Earth Observation, ESRIN, in Frascati, Italy manages the PDGS and carries out checks to assure the quality of the data.
In addition to the Level-0 and Level-1 processing carried out by the PDGS, a European consortium of scientific institutions is responsible for processing the Level-1 data to Level-2 products. These products are also disseminated to the Swarm user community.
Level-0 – time-ordered raw data as measured by the Swarm satellites
Level-1 – time series along the satellites’ orbit for the various instruments
Level-2 – scientific models of magnetic fields originating from various sources and upper-atmosphere phenomena