Photos: X-37B gallery archive

With the Delta 4 rocket now waiting on the launch pad, its Air Force Wideband Global SATCOM communications satellite payload has jetted from the Los Angeles factory to the Cape Canaveral in preparation for liftoff this summer.

Two pioneering communications satellites purely powered by plasma rocket thrusters lifted off from Cape Canaveral aboard a Falcon 9 launcher Wednesday, starting missions to broadcast video across Asia and Latin America, and improve navigation for airplanes crossing the United States.

The 330-foot tall mobile service tower is rolled away from the United Launch Alliance Delta 4 rocket at Cape Canaveral’s pad 37B in the hours before the scheduled liftoff on Dec. 7 at 6:53 p.m. EST (2353 GMT).