Rocket With Spy Satellite Explodes Just After Launch : Space: Loss of Titan IV may be costliest mishap since Challenger. Debris disintegrates over Pacific Ocean.

An unmanned Titan IV rocket carrying a top-secret spy satellite exploded Monday moments after launch from Vandenberg Air Force Base in what civilian space experts said may be the most expensive U.S. space accident since the Challenger disaster.

“Between the cost of the spacecraft and the cost of the satellite, this was a $2-billion accident,” said John Pike, director of the space policy project at the Federation of American Scientists in Washington. “That is the equivalent of this year’s space station budget.”

“For the cost of this accident, everybody in America could see ‘Jurassic Park,’ ” he said.

Air Force officials would not identify the satellite aboard the rocket. But Pike, a national security analyst, said the Titan carried a Lacrosse radar imaging satellite--one of the most secret, sophisticated and expensive tools in the U.S. space reconnaissance network.

Vandenberg officials estimated the cost of the rocket and its launch at about $200 million, but refused to discuss the cost of the satellite or any other details concerning the payload. Pentagon officials could not be reached for comment.

The 200-foot-tall Titan IV is the most powerful U.S. rocket. The Air Force has used it for its heaviest payloads almost exclusively since the Challenger accident in 1986 as a more reliable alternative to the manned space shuttle. Monday’s Titan IV launch was the seventh since 1989.

Air Force officials said the Titan was launched from Vandenberg at 12:59 p.m. and exploded two minutes later over the Pacific Ocean, about 60 miles offshore, before its first-stage booster rockets finished firing. Vandenberg is on the Santa Barbara County coast north of Lompoc.

“We had a normal liftoff and what appeared to be a nominal flight for about 100 seconds before the explosion,” said Maj. Billy E. Birdwell, director of public affairs for the Air Force 30th Space Wing at Vandenberg. “The explosion occurred before first-stage separation, before the solid rocket motors separated.

“Instants later, there was nothing left except debris falling toward the ocean,” he said.

Air Force officials said they did not yet know why the rocket exploded, but the Associated Press reported that the rocket’s two 110-foot solid-fuel boosters appeared to separate prematurely just before the explosion.

The loss of the satellite leaves an important gap in the U.S. space spy network at a time when the CIA and the National Reconnaissance Office--which manages the secret satellite network--have been attempting to stave off budget cuts to their space surveillance program, Pike said.

The annual cost of the U.S. surveillance satellite network is classified, but experts estimate it at more than $6 billion.

Civilian space experts said at least one Lacrosse satellite was launched in 1988 from the space shuttle and is believed to be nearing the end of its operational life. The satellite destroyed Monday was its scheduled replacement.

“In terms of overall intelligence abilities, it is not a crippling loss,” Pike said. “We still have twice as many imaging satellites as we did when the Soviet Union invaded Afghanistan, and the ones we have are much more effective.

“We are getting 10 times as many pictures today from orbit as we did during the Cold War,” he said.

The Lacrosse satellite, powered by enormous wings of solar panels, uses unusual imaging radar instead of a camera to record hundreds of detailed images every day through the densest cloud cover, foliage or complete darkness. This technology, called synthetic aperture radar, is so sensitive that it can penetrate dirt or sand to reveal features buried just beneath the surface, such as missile silo doors or fortifications, experts said.

The images it constructs from its giant phased-array antenna are detailed enough for analysts to identify aircraft on runways, vehicles in military convoys or mobile missile carriers, experts said.

Air Force officials said the accident would not delay the Sunday launch from Vandenberg of an Atlas rocket carrying a civilian weather satellite.

It was too soon to know if the scheduled launch of a Titan IV rocket from Cape Canaveral with a classified payload would have to be postponed until investigators have determined the cause of Monday’s explosion.