China has become just the second country after the United States to achieve the controlled recovery of a reusable orbital space rocket. Friday’s successful capture at sea of the booster stage of a Long March-10B rocket after its maiden launch used a novel technique different from that of Elon Musk’s recently listed SpaceX and previous Chinese attempts. Instead of landing using extendable hydraulic legs, the rocket stage used its engines to position itself over a floating platform in the South...