So far,eight of the ten EQM scientific instruments have been delivered to Turin and five of them - CONSERT, ALICE, COSIMA, VIRTIS and RPC - are integrated with the spacecraft's Payload Module. In the next few weeks, they will be joined by MIRO, GIADA and MIDAS. The remaining two instruments (OSIRIS and ROSINA) and the Rosetta lander are scheduled to arrive in early September.

Integration of the instruments extends over several months, but, as Claude Berner, the Rosetta Payload Operations Manager, explained, piecing together a complex spacecraft requires a slow, painstaking approach.

"Apart from the mechanical procedure of integrating the instruments, it involves testing them and their electrical interfaces," he said. "This means we have to send commands, see if they operate with the power on and then switch to their operational modes."

Claude is cautiously optimistic that all is going well.

"We're half way through the payload and keeping to our very tight schedule," he said. "So far, I'm delighted to say we have not encountered any major problems."

At the same time, work is continuing on the Rosetta EQM Service Module. Major subsystems already integrated on the module include the command management unit, the remote terminal unit which acts as a telemetry/telecommunications interface, and the power control and distribution units. In the coming weeks, the telecommunications subsystems will be added.

All of this work on the Rosetta orbiter EQM should come together at the end of September with the mating of the Payload Module and Service Module.