Flight Operations Segment (FOS)
The Flight Operation Segment (FOS) is responsible for command and control of the satellite and is operated from ESA’s European Space Operations Centre (ESOC) in Darmstadt, Germany.
Figure 1: ESA's European Space Operations Centre
The FOS consists of the Ground Station and Communications Network, Flight Operations Control Centre and a General Purpose Communication Network.
The FOS provides the capability to monitor and control the satellite during all mission phases including the Flight Dynamics System facility responsible for orbit determination and prediction, and for the generation of attitude and orbit control telecommands.
The main functions of the FOS include:
Spacecraft status monitoring
Orbit determination and control
Attitude determination and control
On-board software maintenance