Watch Falcon 9 rocket lifted upright

NASA officials say the International Space Station’s logistics chain was designed to absorb a launch failure like the mishap that destroyed an Orbital Sciences Corp. cargo craft in October, but pressure is on SpaceX to deliver supplies on time this year.

Flight controllers at NASA’s mission control center in Houston have completed the robotic swap out of a failed power distribution unit outside the International Space Station, clearing a hurdle ahead of Friday’s predawn launch from Cape Canaveral of a SpaceX supply ship.

Veteran Soyuz commander Yuri Malenchenko, outgoing space station skipper Tim Kopra and British astronaut Tim Peake departed the International Space Station early Saturday aboard the Soyuz TMA-19M capsule and landed in Kazakhstan at 0915 GMT (5:15 a.m. EDT).