A SpaceX Falcon 9, with NASA astronauts Doug Hurley and Bob Behnken in the Dragon crew capsule, lifts off from Pad 39A at the Kennedy Space Center in Cape Canaveral, Fla., on Saturday.

A SpaceX Falcon 9, with NASA astronauts Doug Hurley and Bob Behnken in the Dragon crew capsule, lifts off from Pad 39A at the Kennedy Space Center in Cape Canaveral, Fla., on Saturday.