Citing national security,the Air Force did not volunteer much information about this reported $1.4billion mission for the NationalReconnaissance Office except to confirm a successful launch and spacecraftseparation.

The NRO won't identify whatis flying on this Titan rocket either, but industry observers agree thesecret payload is most likely an intelligence-gathering satellite equippedwith a powerful radar that is capable of looking through clouds to capturehigh-resolution images of Earth's surface.

Code named Onyx, the satelliteis likely being launched to replace an aging radar satellite that wentby the name of Lacrosse, said John Pike, director of space policy for theFederation of American Scientists, a private government watchdog groupthat specializes in military and technology issues.

Information gathered by thesespy satellitesis provided to the military to help monitor problem spots around the world,as well as help accurately target weapons in almost real time, Pike said.

NRO spokesman Art Hauboldwould not comment on the spacecraft's identity, offering only that "thismission is yet another part of our mission to provide global informationsuperiority for the United States."

The NRO has operated spysatellites for the intelligence community for 40 years, an anniversarythe organization will be marking this weekend, Haubold said.

It's been 40 years sincethe first secret images were returned from space for the NRO.

During those early days ofthe Cold War, a satellite program called Corona orbited spacecraft thattook pictures by exposing film. The film was then returned to Earth ina capsule that was snagged in midair by an airplane.