The first satellites of the Galileo constellation, Europe's own navigation system, will be launched by pair on a Soyuz from French Guyane later this year. Four satellites are currently being prepared in Europe for what is called the in orbit validation phase: a full scale demonstration of what will be Galileo with 4 satellites on orbit working together with deidcated ground infrastructure. One of these satellites model was recently tested at ESA test facilities at ESTEC in the Netherlands.