Video: Highlights of weekend’s Delta 2 launch

If all goes according to plan, engineers in southern Mississippi later this month will load cryogenic propellants into the core stage of a rocket NASA says will launch astronauts back to the moon, exposing its tankage and internal plumbing to extreme operating conditions hundreds of degrees below zero for the first time. The fueling test — a major milestone in its own right — is a precursor to a high-stakes eight-minute test-firing of the Space Launch System’s four shuttle-era main engines planned as soon as November.

Two weeks after a sensor problem forced a delay, an Ariane 5 rocket blasted off at 6:04 p.m. EDT (2204 GMT) Saturday from French Guiana with two commercial communications satellites to cover the United States and Japan, and a Northrop Grumman-built robotic satellite servicing mission designed to link up with another spacecraft in geostationary orbit.

SpaceX completed Friday the last drop test of the Dragon crew capsule’s parachutes before the first launch of astronauts on the human-rated ship May 27, while technicians at Cape Canaveral have mated the spacecraft’s crew module with its unpressurized trunk section.