Photos: Atlas 5 on the pad for X-37B launch

Video highlights of the 50th Atlas 5 flight. The United Launch Alliance rocket carried the eighth Global Positioning System (GPS 2F-8) satellite for the U.S. Air Force.

Look back on the launch Saturday of a Northrop Grumman Antares rocket from Wallops Island, Virginia, powered by a pair of kerosene-fueled RD-181 engines producing 864,000 pounds of thrust.

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.