A simulated EPIC camera deep-field exposure. Photo: ESA

All of the European Space Agency's X-ray Multi-Mirror observatory's instruments have been switched on and their computer software loaded on board. The first task has been to check the health of the instruments repeating the engineering test procedure used on the ground before launch. This has confirmed that all instruments remain in the same condition as before launch. This was also the 'acid test' to verify that the instrument data sent by the spacecraft were reaching Villafranca and were being processed correctly.

On January 4, to everyone's relief, the first data arrived and were processed correctly by the new software installed at the XMM Science Observations Centre. Watching this important event, XMM project manager Robert Laine commented: "I saw big smiles all around when EPIC then later test images appeared on the screen."

All the data collected are now being processed in detail by the various institutes which contributed to the development of XMM scientific instruments.

Currently all instruments are in the 'shut' position (i.e. not looking at the sky) and will remain this way until all parameters of the instruments have been analysed and understood.

Later this month one by one the X-ray cameras will be opened briefly to have a peek at the real sky. Again the data collected will be analysed before the start of routine operations. The reason for this careful step-by-step deployment of the instruments is to make ensure that there is no surprise degradation of the detectors, for example due to a sudden solar flare sending a heavy dose of high energy radiation and increasing the altitude of the earth radiation belts. In such a case the protective shutters of the cameras would be shut; but of course the operators have first to gain experience in controlling the delicate instruments of XMM before exposing them to the harsh 'space weather'.