Photos: Gantry rollback from Delta 2

Early Friday morning, the 8-million-pound mobile service tower was retracted from around the Atlas 5 rocket, revealing the 189-foot-tall vehicle for liftoff from Vandenberg Air Force Base, California, carrying the commercial WorldView 4 Earth-imaging satellite.

A commercial rocket under development by Firefly Aerospace will conduct its first orbital test flight in 2019 from a launch pad at Vandenberg Air Force Base in California that will become vacant with the retirement of the venerable Delta 2 booster later this year, the company announced Tuesday.

The United Launch Alliance Delta 2 rocket lifts off with NASA’s SMAP observatory at 6:22 a.m. local time on Saturday, Jan. 31 from Vandenberg Air Force Base in California.