Endeavour Finally Lifts Off on Science Satellite Mission

KENNEDY SPACE CENTER, Fla. — Its flight delayed a month by O-ring trouble, space shuttle Endeavour thundered into orbit with five astronauts Thursday on a mission to release and recapture a pair of science satellites.

The 4.5 million-pound spaceship rose through thin clouds ahead of approaching storms.

O-ring seals in the nozzles of Endeavour’s solid rocket boosters had to be fitted with new insulation last month after NASA discovered singe marks on the rings in two other shuttles. The Challenger shuttle disaster in 1986 was blamed on a leak of hot gas through a set of O-rings.

NASA officials said it will be days before they know whether the O-rings in Endeavour escaped damage.

The booster repairs, along with a power generator that overheated hours before a launch attempt last week, had held up the flight almost five weeks.

“Every dog has its day and today is your day,” Roger Gillette, a launch official, told the astronauts shortly before liftoff.

As soon as Endeavour reached orbit, commander David Walker announced: “The dogs are in space.”

Walker and his crew jokingly call themselves “the Dog Crew” for reasons that aren’t entirely clear. They barked on the way to the launch pad and posed for breakfast pictures with personalized dog bowls.

Their first order of business is to release an $8-million satellite to study streams of charged particles hurtling away from the north pole of the sun at 500 miles a second. The satellite, called Spartan, will be set free today and retrieved Sunday.

Then on Monday, the astronauts will release a $25-million, dish-shaped satellite to produce thin film for semiconductors. The crew will pick up the satellite two days later.

Scientists hope the ultra-pure vacuum created in the satellite’s wake will produce film of unprecedented quality. The satellite could not be released from the shuttle Discovery last year because of a sensor and wiring problem.

On Sept. 16, two astronauts will walk in space to practice techniques and test equipment for building a space station. The flight will end Sept. 18.