An unmanned heavy-lift Atlas 5 rocket blasted off from Cape Canaveral Air Force Station in Florida on Thursday to put a secret payload into orbit.
The rocket, built by Lockheed Martin Corp. and marketed under a new Lockheed-Boeing Co. joint venture called United Launch Alliance, lifted off at 11:12 a.m. EDT (1512 GMT) and headed out over the Atlantic Ocean.
The launch was for the U.S. National Reconnaissance Office, which develops and operates the nation's spy satellites.
Details about the rocket's destination and payload were not released. The industry trade magazine Aviation Week and Space Technology reported in April that the Atlas rocket would carry a pair of ocean surveillance satellites.
The launch was the first Atlas V flight for the National Reconnaissance Office. All nine previous flights of the Atlas V have been successful.