Rocket Blasts Satellite Toward a Proper Orbit : Space: The reboost is flawlessly accomplished. Two astronauts perform mission’s last planned spacewalk.

The stranded communications satellite rescued by three shuttle astronauts blasted toward its proper orbit Thursday, ending a dramatic effort that in the words of NASA’s top official “brought the magic back to our space program.”

The 23,000-pound rocket motor clamped to the marooned Intelsat 6 by the crew of space shuttle Endeavour fired flawlessly at 10:25 a.m. PDT while both were orbiting about 230 miles over Africa, said a spokesman for the International Telecommunications Satellite Organization. The 122-nation consortium, based in Washington, owns and operates the $150-million satellite.

The reboost capped a dramatic, four-day rescue effort in which astronauts were forced to discard a specially designed, $7-million tool that failed to snag the errant satellite, and instead literally reached up and grabbed the Intelsat with their gloved hands.

Wednesday’s 8-hour, 29-minute spacewalk, which includes the time astronauts spent in the shuttle airlock, was the longest in the history of the American space program.

“It was a wonderful feat,” said Daniel S. Goldin, the new administrator of the National Aeronautics and Space Administration. The successful rescue, Goldin argued, is an endorsement of the nation’s manned space program, which has come under attack by some in Congress because of its expense. The planned space station Freedom, for example, is expected to cost between $30 billion and $40 billion through the end of the decade.

In the last planned spacewalk of the mission Thursday, Air Force Lt. Col. Thomas D. Akers, 40, and physicist Kathryn C. Thornton, 39--only the second American woman to walk in space--ventured out of the shuttle at 2:07 p.m. PDT to practice techniques that will be used in building the space station.

Their task was to assemble a package of struts, some of which were used in Wednesday’s satellite rescue, into a pyramid-like structure secured in the shuttle’s open cargo bay. The structure then was lifted high over the bay by the shuttle’s 50-foot robot arm.

After snagging Intelsat 6 Wednesday and attaching the new booster rocket, the shuttle crew released the satellite, which was allowed to drift away. The two were more than 400 miles apart by the time Intelsat 6’s rocket motor was fired Thursday. After the fiery reboost, which was visible from the shuttle, the motor separated from the satellite at 11:51 a.m. PDT, and Intelsat 6 streaked into a temporary elliptical orbit that will take it as far as 45,000 nautical miles from the Earth. By next Wednesday, the satellite is expected to settle into its stationary, geosynchronous orbit 22,300 nautical miles over the Atlantic Ocean.

When it begins operating in mid-July, the satellite will be able to simultaneously transmit 120,000 telephone calls and three television feeds. It is expected to earn more than $750 million for Intelsat over its 10-year life.

Goldin offered lavish praise for the Intelsat rescue.

“What we have done,” Goldin said, “is demonstrate that humans can and should operate in space.” He spoke of “brilliance of the human mind, that’s able to adapt and react and do the things that machines just can’t do.”

“In front of the eyes of the world, they performed the impossible. . . . Yesterday brought the magic back to our space program.”

At Intelsat headquarters, consortium Vice President Pierre Madon said: “Clearly, this is a magnificent day for both Intelsat and NASA. . . . I offer my hearty congratulations to the crew of Endeavour and NASA for a job well done.”

Even as Goldin was congratulating the seven Endeavour astronauts and flight controllers at the Johnson Space Center for the rescue, NASA engineers were searching for lessons in the trouble-plagued mission, which is to end Saturday with a scheduled 1:57 p.m. PDT landing at Edwards Air Force Base in California.

“One of the preliminary factors we’re learning about is how to do better simulations on the ground,” Goldin said Thursday.