Live coverage: Chinese sample return spacecraft completes docking in lunar orbit

SpaceX is preparing this week for the second flight of the upgraded “Block 5” version of the company’s Falcon 9 rocket, and a hold-down firing of the booster was accomplished Wednesday at Cape Canaveral ahead of a middle-of-the-night launch this weekend with a Canadian-owned commercial communications satellite. The static fire test occurred at 5 p.m. EDT (2100 GMT) Wednesday.

The United Launch Alliance Atlas 5 rocket, standing 194 feet tall and and weighing a million pounds, unleashes 1.6 million pounds of thrust from its main engine and two side-mounted solid boosters to launch the secret NROL-52 payload for the U.S. National Reconnaissance Office from Cape Canaveral.

A Northrop Grumman Antares rocket launch April 17 from Virginia’s Eastern Shore marked the start of the 11th Cygnus resupply mission to the International Space Station.