Live coverage: Atlas 5 countdown and launch journal

Work to create a new all-American rocket, the United Launch Alliance Vulcan-Centaur, has passed its first major hurdle for its first flight in three years, officials announced Thursday.

The United Launch Alliance Delta 4 Medium+ (4,2) rocket lifted off at 12:52 a.m. EDT (0452 GMT) from Cape Canaveral for the Geosynchronous Space Situational Awareness Program.

A United Launch Alliance Atlas 5 rocket with a new type of solid rocket booster emerged from its hangar Tuesday evening for the 1,800-foot rollout to pad 41 at Cape Canaveral, moving into position for liftoff Wednesday with a classified National Reconnaissance Office payload.