The Giove-B satellite was taken into space atop a Soyuz rocket which left Earth at 2216 GMT, Saturday. The demonstrator will test the key technologies which will eventually be built into the 30 operational platforms that form the Galileo network.
These include the atomic clocks which provide the precise timing that underpins all sat-nav applications.
Giove-B - a half-tonne, 2.4x1x1m box assembled by EADS Astrium and Thales Alenia Space - is the second demonstrator satellite to go into orbit following the launch of Giove-A in 2005. The first mission met international obligations to claim the frequencies Galileo will use to transmit its signals to receivers on the ground.
This second mission flies a spacecraft which is, to a large degree, a template for the 30 operational platforms that will follow.
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