MARCIA DUNN, AP Aerospace Writer

CAPE CANAVERAL, Fla. (AP) — Atlantis and four astronauts thundered into orbit Friday on NASA's last space shuttle voyage, writing the final chapter in a 30-year story of dazzling triumphs, shattering tragedy and, ultimately, unfulfilled expectations.

After days of gloomy forecasts full of rain and heavy cloud cover, the spaceship lifted off at 11:29 a.m. — just 2½ minutes late — and embarked on the 135th shuttle mission. The crowd of spectators was estimated at nearly 1 million.

"Let's light this fire one more time," Commander Christopher Ferguson said just before taking flight.

The shuttle was visible for 42 seconds before disappearing into the clouds.

It will be at least three years — possibly five or more — before astronauts are launched again from U.S. soil, and so this final journey of the shuttle era packed in crowds and roused emotions on a scale not seen since the Apollo moon shots. NASA has set of long-term goal of flying to an asteroid and eventually Mars.

"Take a deep breath. Enjoy a little time here with your families again. But we've got a lot of work to do. We've got another program that we've got to get under way," NASA Administrator Charles Bolden told the launch control team after Atlantis reached orbit. He added: "We know what we're doing. We know how to get there. We've just got to convince everybody else that we know what we're doing."

Atlantis' crew will deliver a year's worth of critical supplies to the International Space Station and return with as much trash as possible. The spaceship is scheduled to come home on July 20 after 12 days in orbit.

The four experienced space fliers rode Atlantis from the same launch pad used more than a generation ago by the Apollo astronauts. NASA waived its own weather rules in the final minutes of the countdown to allow the launch to go forward. In the end, though, the liftoff was delayed not by the weather but by the need to verify that the launch pad support equipment was retracted all the way.

The last-minute suspense was fitting in a way, since Florida's famously stormy weather delayed numerous shuttle missions almost from the start of the program and was a major reason spaceflight never became routine, as NASA had hoped for.

Spectators jammed Cape Canaveral and surrounding towns for the emotional farewell. Kennedy Space Center itself was packed with shuttle workers, astronauts and 45,000 invited guests.

NASA's original shuttle pilot, Robert Crippen, now 73, was among the VIPs. He flew Columbia, along with Apollo 16 moonwalker John Young, on the inaugural test flight in 1981. Other notables on the guest list: a dozen members of Congress, Cabinet members, the chairman of the Joint Chiefs of Staff, four Kennedy family members, singers Jimmy Buffett and Gloria Estefan, and two former NASA chiefs.

"I'm a little bit sad about it, and a little bit wistful," said Jennifer Cardwell, 38, who came with her husband, John, and two young sons from Fairhope, Ala. "I've grown up with it."

The space shuttle was conceived even as the moon landings were under way, deemed essential for building a permanent space station. NASA brashly promised 50 flights a year — in other words, routine trips into space — and affordable service.

But the program suffered two tragic accidents that killed 14 astronauts and destroyed two shuttles, Challenger in 1986 and Columbia in 2003. NASA never managed more than nine flights in a single year. And the total tab was $196 billion, or $1.45 billion a flight.

Yet there have been some indisputable payoffs: The International Space Station would not exist if it were not for the shuttles, and the Hubble Space Telescope, thanks to repeated tuneups by astronauts, would be a blurry eye in the sky instead of the world's finest cosmic photographer.

The station is essentially completed, and thus the shuttle's original purpose accomplished. NASA says it is sacrificing the shuttles because there is not enough money to keep the expensive fleet going if the space agency is to aim for asteroids and Mars.

Thousands of shuttle workers will be laid off within days of Atlantis' return from its 33rd flight, on top of the thousands who already have lost their jobs. And the three remaining shuttles will become museum pieces.

After Atlantis took flight, NASA launch director Mike Leinbach choked up as he thanked the members of his control team, some of whom will be out of a job. "The definition of godspeed I like the best is 'have a prosperous journey,' and folks, from the bottom of my heart, good luck and godspeed," he said.

This day of reckoning has been coming since 2004, a year after the Columbia tragedy, when President George W. Bush announced the retirement of the shuttle and put NASA on a course back to the moon. President Barack Obama canceled the back-to-the-moon program in favor of trips to an asteroid and Mars.

But NASA has yet to work out the details of how it intends to get there, and has not even settled on a spacecraft design.

The space shuttle demonstrates America's leadership in space, and "for us to abandon that in favor of nothing is a mistake of strategic proportions," lamented former NASA Administrator Michael Griffin, who led the agency from 2005 to 2008.

After Atlantis' lights-out flight, private rocket companies will take over the job of hauling supplies and astronauts to the space station. The first supply run is targeted for later this year, while the first trip with astronauts is projected to be years away.

Until those flights are up and running, American astronauts will be hitching rides to and from the space station via Russian Soyuz capsules, at more than $50 million per trip.

Russia will supply the rescue vessels for Ferguson and his crew if Atlantis ends up severely damaged in flight. But the Russian spaceships can carry only three people, including two crew members, and any rescue would require a series of back-and-forth trips. That is why only four astronauts are flying Atlantis, the smallest crew in decades.

When Atlantis returns, it will be put on display at the Kennedy Space Center. Discovery and Endeavour already are retired and being prepped for museums in suburban Washington and Los Angeles.

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Associated Press writers Mitch Stacy in Titusville, Fla., and Seth Borenstein at Cape Canaveral contributed to this story.

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