The shuttle was launched at the conclusion of a countdown that seemed touched by good fortune: nearly perfect weather and none of the technical problems that can cause last-minute delays.

During the eight-and-a-half minute ascent, problems were announced over the communications loop with the shuttle’s reaction control system, which provides thrust for maneuvers, and the flash evaporator system, which helps cool equipment until the payload bay doors are opened on orbit. Neither problem, however, interfered with Endeavour’s climb to orbit.

In a press briefing an hour after the launching, LeRoy Cain, the manager of launch integration at Kennedy Space Center, called the two problems “very minor issues” that could be worked around without any impact on completion of the mission. Mr Cain also said that no significant foam loss was observed in a preliminary look at videos, though he said the images would be examined more closely in coming days.

The shuttle will catch up with the station and dock just before midnight on Wednesday. The mission, the longest visit by a shuttle to the International Space Station, is packed with tasks for seven astronauts who are bringing the first part of a new Japanese laboratory, Kibo, to the station, as well as a gangly two-armed robot named Dextre.

With the arrival and installation of the first piece of Kibo, components from all of the major partners in the space station — the United States, Russia, Canada, Europe and Japan — will finally be joined in the orbital outpost. The Kibo module will be put in a temporary spot on the station until the main structure is carried to space and installed in the next shuttle mission in April.

Dextre, which was made in Canada and has the eerily anthropomorphic look of a robot from science fiction, was designed to do some of the external servicing jobs that humans perform today. It will work with the station’s robotic arm or ride on a mobile platform that runs along rails on the station’s trusses.

The mission includes five spacewalks that will be mostly devoted to the work on Kibo and Dextre. One of the spacewalks will be devoted to testing a zero-gravity goo gun that could be used to repair small areas of damage to the shuttle’s delicate heat-shedding tiles. The device was developed after the Columbia disaster on February 1, 2003: the shuttle and crew were lost because insulating foam fell off of the fuel tank during ascent and damaged the craft.

NASA has expended tremendous effort since then to reduce the amount of foam shed by the tank, and minute inspection of the heat shield is now part of each mission. But the independent board that investigated the disaster recommended developing tile repair techniques as well, and the “tile repair ablator dispenser” is one of the products that came out of that work. Mission managers wanted to perform that test before astronauts returned to the Hubble Space Telescope for a servicing mission later this year, since the shuttle would not be able to change course and reach the space station if the tiles were damaged on ascent.

During this mission, crew members will also inspect a damaged rotary joint that is supposed to turn the station’s solar panels toward the sun through each orbit. Mission managers took the 10-foot-in-diameter joint out of commission last year after inspections showed the works were peppered with metal shavings — a sign of metal-on-metal grinding. The astronauts will examine the joint closely and will replace a bearing that was taken off for inspection on a previous flight.

NASA is still trying to determine how best to address that problem and get the joint rolling again so that the station can receive all the power that the system was designed to produce.

The commander for this mission is Dominic L. Gorie, a retired Navy captain, and the pilot is Col. Gregory H. Johnson of the Air Force. Other member of the crew include Richard M. Linnehan; Capt. Michael J. Foreman of the Navy; Maj. Robert L. Behnken of the Air Force; Takao Doi, a Japanese astronaut; and Garrett E. Reisman, an astronaut who will be staying aboard the station for long-term duty. He will take the place of Gen. Léopold Eyharts, a French astronaut who has lived aboard the station since last month.

Shortly before launching, the shuttle launch director, Michael Lenbach, opened a channel to Captain Gorie and informed him that the team backed the decision to launch. “Good luck, godspeed and we’ll see you back here in 16 days,” he said.

“Well, Mike, you just made people smile around the world,” he responded, referring to the international participants in the station program, “and you’ve got seven smiling faces on board here.” He thanked the launch team and the crew’s families, spoke a few words of thanks in Japanese, and finished by saying, “God truly has blessed us with a beautiful night to launch, so let’s light them up and give ‘em a show.”

Lifting of on schedule at 2:28 a.m., the shuttle lit the night with a yellowish-orange glow, and quickly punched through a low cloud bank and flew out of sight.