Space shuttle Atlantis lifts off Friday from the Kennedy Space Center at Cape Canaveral, Fla. Atlantis’ 12-day mission will deliver a Russian-built storage and docking module to the International Space Station.

Cape Canaveral, Fla. ? Space shuttle Atlantis thundered away on its final voyage to orbit Friday, hoisting an experienced crew of six and a full shipment of space station gear.

Atlantis sped through a perfectly clear afternoon sky, blazing a trail over the Atlantic before huge crowds eager to catch one of the few remaining shuttle launches. More than 40,000 guests — the biggest launch-day crowd in years — packed the Kennedy Space Center.

The shuttle’s destination is the International Space Station, which was soaring over the South Pacific at the time of liftoff. The shuttle should catch up with the orbiting complex and its six residents Sunday morning.

A piece of orbiting junk, however, was threatening to come too close to the space station. If necessary, Mission Control will order up a maneuver so the station can dodge the debris the night before Atlantis’ arrival. The docking will not be delayed, even if the station has to move out of the way of the unidentified piece, NASA officials said.

“Good luck, godspeed and have a little fun up there,” launch director Mike Leinbach told the astronauts just before liftoff. He said he was speaking on behalf of all those who have worked on Atlantis since construction began in 1980.

“Like you said, there are thousands of folks out there who have taken care of this bird for a long time,” replied commander Kenneth Ham. “We’re going to take her on her 32nd flight, and if you don’t mind, we’ll take her out of the barn and make a few more laps around the planet.”

The astronauts — all repeat space fliers and all men — couldn’t resist a little humor before they got down to business. They showed up for their steak and cheeseburger breakfast wearing blue and black smoking jackets, white shirts and black bow ties.

This 12-day mission is the last one planned for Atlantis, the fourth in NASA’s line of space shuttles. Only two flights remain after this one, by Discovery and Endeavour. NASA plans to end the 30-year program by the end of this year.

Atlantis — which rocketed into orbit for the first time in 1985 — is loaded with fresh batteries and a Russian-built compartment for the space station. The 20-foot-long module is crammed with food, laptop computers and other U.S. supplies.

Ham and his men will install the compartment on the space station, and carry out three spacewalks to replace six old batteries and hook up an antenna and other spare parts.

Alexey Krasnov, chief of the Russian Space Agency’s piloted program, said it was a miracle that Atlantis took off without any delays.

“It looks like that Atlantis is telling us, ‘Please use me again. I am capable,’ ” he said, smiling. “Maybe two-thirds of the launches were postponed by the weather or hardware … and today it worked exactly as planned.”

Only a few small bits of insulating foam were seen coming off the fuel tank during liftoff, nothing significant, officials said.

Launch spectators included Defense Secretary Robert Gates and late-night TV host David Letterman, as well as dozens of Russians. About 150 Twittering guests watched from Kennedy’s media complex.

Matt Balan, 29, of Alexandria, Va., lost his network connection right at liftoff as he was trying to tweet. He finally got this message out a few minutes after the fact: “That was spectacular!!!!”

Even off-duty astronauts marveled at the sight of Atlantis rising one last time, snapping pictures with their cell phones. “That was an incredible launch,” said Rick Mastracchio, who flew last month on Discovery. Some Apollo astronauts also showed up.

President Barack Obama wants NASA to focus on getting astronauts to an asteroid by 2025 and into orbit around Mars by 2035. He canceled the previous administration’s plan to return to the moon.