The first two, KOERI in Turkey and the Atomic Energy Centre in France, should be operational some time in 2012 when a more exhaustive test will be conducted.

UNESCO: EDUCATION

The Cadarache site lies about 60km (37 miles) inland from Marseille, and has been a nuclear research centre ever since President Charles de Gaulle launched France's atomic energy programme in 1959.

BBC: NEWS | Science/Nature | Fusion reactor work gets go-ahead

Astrium's role, at its UK centre in Portsmouth, was to integrate all the payload components, including hydrogen-maser atomic clocks, the ultra-precise time-pieces on which Galileo's performance depends.

BBC: Galileo: Europe's version of GPS reaches key phase