Herschel Flight Model Service Module
Herschel's service module is seen from below as the spacecraft flight model is hanging from a crane. The spacecraft is being hoisted from its transporter truck onto the multi-purpose trolley inside the cleanroom at ESTEC.
In the centre of the octagonal shaped service module the two startrackers are seen (with their orange protective covers) between two helium tanks (silver spheres). The service module contains the systems needed to operate the spacecraft: power, attitude and orbit control, spacecraft control and data management, RF communications. It also houses those parts of the instruments that do not require cooling.