Photos: California’s predawn liftoff of Atlas 5 rocket

The United Launch Alliance Atlas 5 rocket, standing 197 feet tall and and weighing 1.2 million pounds, unleashes 2.4 million pounds of thrust from its main engine and four side-mounted solid boosters to launch the secret NROL-42 payload for the U.S. National Reconnaissance Office from Vandenberg Air Force Base, California.

SpaceX fired three Raptor engines on a prototype of the company’s Starship vehicle Tuesday, accomplishing another milestone on the road toward testing of the methane-fueled rocket at higher altitudes.

The launch of a United Launch Alliance Delta 4-Heavy rocket from Cape Canaveral was aborted three seconds before a planned liftoff at 3:28 a.m. EDT (0728 GMT). The rocket was set to loft a classified payload for the National Reconnaissance Office, the U.S. government’s spy satellite agency.