After launch, XMM had been released by Ariane 5 at 826 km. The first boosts raised the perigee to 4900 km. A final manoeuvre will then adjust the apogee to precisely 114,000 km. Brightly coloured schematics and graphs are displayed on the consoles of the Flight Operations Director, and those of the XMM Project team representatives. On these, can read the temperature and pressure throughout the propulsion system, for example for each of the thrusters as they are firing and the four hydrazine propellant tanks.
Controllers can also obtain a graphic view of what the spacecraft's star trackers are seeing.
For example, on this apogee passage, five stars are represented. It is to these points in space that XMM's Attitude and Orbit Control system has locked-on to maintain the spacecraft attitude. XMM has eight main thrusters in two redundant sets. For each perigee boost, one set is activated, the other remain as a backup. All four thrusters work at the same time, providing not only the increase in velocity but also maintaining XMM's orientation.