PARIS — The European version of Russia’s Soyuz rocket on Oct. 12 successfully placed two European positioning, navigation and timing satellites into medium-Earth orbit following launch from Europe’s Guiana Space Center in South America, Europe’slaunch consortium and the European Space Agency ( ) said.
The two Galileo in-orbit validation satellites will join two others already in orbit to permit ESA to perform initial tests of what ultimately is intended to be a 30-satellite constellation of Galileo spacecraft, Europe’s version of the U.S. GPS, Russian Glonass and Chinese Beidou constellations.
The four validation satellites, each weighing about 700 kilograms at launch, will operate from 23,000 kilometers in altitude. The spacecraft were built by a consortium led by Europe’s Astrium, and including.
The two spacecraft launched Oct. 12 are identical in most respects to the two launched aboard the Europeanized Soyuz in October 2011. But the second pair includes a search-and-rescue payload that had to be removed from the initial satellites because the equipment was built in China.
The European Commission, which owns Galileo, had decided late in the first satellites’ development that it could not accept a Chinese subsystem on the Galileo constellation. A Canadian alternative was also rejected, for similar made-in-Europe reasons.
A replacement supplier, Kongsberg Norspace of Norway, was eventually found despite Norway’s not being a member of the European Union.
The next 22 Galileo satellites are under construction by a consortium led by OHB AG of Germany, with Surrey Satellite Technology Ltd. of Britain providing the payloads. These satellites are scheduled to begin launches – also aboard the European Soyuz for the initial deliveries – in the spring of 2013.
The European Commission has not yet contracted the remaining satellites needed to fill out the 30-satellite constellation.
ESA and the European Union have set a goal of having 18 Galileo satellites in orbit by the end of 2014.