Europe launches third and fourth Galileo satellites

Testing of Europe’s Galileo satellite navigation system can begin following the launch of two additional operational satellites.  The two new satellites, named David and Sif1, were launched from Kourou, French Guiana, using a Soyuz launcher late last week and have joined another pair of satellites that have been orbiting the Earth since October 2011. This mini-constellation of four satellites will facilitate Galileo’s validation and fine-tuning—a further 14 ...