Video: SpaceX test-fires Falcon 9 rocket at pad 40 (members only)

Boosted by two solid-fueled motors and a hydrogen-burning main engine, a European Ariane 5 rocket took off Thursday from French Guiana with a Japanese military communications payload and a U.S.-built, British-owned broadband satellite, returning to service after a January mission placed two spacecraft in the wrong orbit.

A steel tube built as a stand-in for the core stage of NASA’s Space Launch System has arrived at the Kennedy Space Center for a series of rehearsals to hone the skills of technicians before the real rocket reaches the spaceport, an oft-delayed milestone that could still be a year or more away.

Several NASA astronauts, plus Boeing test pilot Chris Ferguson, recently participated in a training session at Cape Canaveral, practicing how they would evacuate from the Atlas 5 rocket’s launch pad in the event of a countdown emergency.