Photos: Gantry rollback from Delta 2

Flying for the 155th and final time, a United Launch Alliance Delta 2 rocket took off from California on Sept. 15 with NASA’s ICESat 2 satellite.

The United Launch Alliance Delta 2 was launched Saturday at 6:22 a.m. local time with NASA’s Soil Moisture Active Passive (SMAP) satellite from Vandenberg Air Force Base in California.

Ground crews at Vandenberg Air Force Base in California retracted a mobile gantry away from the Delta 2 rocket Monday afternoon, revealing the 128-foot-tall (39-meter) booster on its launch pad awaiting liftoff with a new polar-orbiting weather observatory.