Video: Liftoff of Atlas 5 with GPS 2F-10

SpaceX test-fired a Falcon 9 rocket at Cape Canaveral on Saturday in a pre-flight checkout designed to verify the launcher’s engines are ready to loft a U.S. military GPS navigation satellite into orbit Nov. 5. An engine problem forced SpaceX to abort a launch attempt in early October.

SpaceX has pushed back the liftoff of a Bulgarian television broadcast satellite on the company’s second previously-flown Falcon 9 rocket until at least Friday, giving ground crews time to replace a valve on the launcher inside a hangar at its Florida launch pad.

A robotic U.S. Air Force space plane is set to land in California as soon as this week after a secretive 22-month flight hundreds of miles above Earth.