European Space Agency

An Ariane 5 rocket emerged from its vertical assembly building Monday and rolled along dual rail tracks for a 1.7-mile (2.7-kilometer) journey to its launch pad at the Guiana Space Center on the northern coastline of South America, moving into position for blastoff Wednesday with four Galileo navigation satellites.

Ground crews in French Guiana on Monday transferred an Ariane 5 rocket to its launch pad, moving the vehicle into position for liftoff Wednesday with four European Galileo navigation satellites on the Ariane 5’s last flight with an older-generation, out-of-production upper stage.