Workers at Cape Canaveral Air Force Base in Florida have stabilized the solid-fuel rocket boosters that lifted the shuttle into space and now begin the process of slowly getting to the joints connecting the rocket segments.

The 126-foot-long white booster rockets apparently worked flawlessly before separating from the space shuttle Discovery two minutes and five seconds after liftoff Thursday."The ordnance devices are off and they're in the process of taking off all the thermal protection stuff," Carver Kennedy, Morton Thiokol vice president of space services, said Monday. "We will not look at any of the joints for several days."

NASA and Morton Thiokol officials hailed the boosters' performance as a success. An intense redesign and re-evaluation process followed the Challenger explosion, resulting in more than 100 changes to the boosters.

To celebrate that success, Morton Thiokol purchased full-page ads in Tuesday's editions of the Deseret News and the Salt Lake Tribune thanking employees who built Discovery's solid rocket moors. "It has been a long hard road back," the ad said. "With you (Thiokol employees) we can face forward again."

Meanwhile, closer examination of the boosters continues.

"We're in the process of taking apart the heaters from the joints," said Kennedy. The thermal-wrap devices keep the booster seals at 75 degrees Fahrenheit before the launch.

The aft-skirt section on the boosters' tail end will be returned to U.S. Boosters Inc., which makes the outside hardware for the rockets, Kennedy said.

"We'll be slowly disassembling," Kennedy said. "It's a rather tedious process. We won't get to the O-rings until this time next week."

The presidential commission that investigated the Challenger explosion blamed a faulty O-ring seal for allowing hot gases to leak and ignite the huge external fuel tank. Seven astronauts were killed, and the shuttle program was grounded while the 21/2-year redesign program was instituted.

An assessment team of representatives from the National Aeronautics and Space Administration, Morton Thiokol and U.S. Boosters Inc. will oversee the disassembly of the booster rockets.

"We'll pull the segments apart and they'll be returned to the (Morton Thiokol) plant in Clearfield," Kennedy said. "The preliminary examination will be done here and the final examination will be done in Utah."

Discovery landed Monday at Edwards Air Force Base in California. It will be shipped to Florida, piggybacked on a jet, and there will be readied for its next flight. Record crowds turned out to cheer the launch and the landing of the first space flight since Challenger blew up in January 1986.