A United Launch Alliance Delta 4 rocket went through a practice countdown and fueling exercise this week to prepare for its Aug. 19 liftoff to deliver a pair of orbital surveillance satellites into space.

A Dragon supply ship owned and operated by SpaceX departed the International Space Station early Monday and returned to Earth for a predawn splashdown in the Pacific Ocean southwest of Los Angeles with scientific specimens and other equipment. Astronaut Jack Fischer released the Dragon cargo capsule from the station’s robotic arm at 2:41 a.m. EDT (0641 GMT), and splashdown occurred around 8:12 a.m. EDT (1212 GMT).

Cape Canaveral was the point of origination for the United Launch Alliance Atlas 5 rocket and the classified NROL-52 payload.