Riding a column of flame and smoke, space shuttle Atlantis glided skyward at 11:29 a.m. Friday, the roar of its rockets building to a ground-shaking rumble as cheers erupted at the Kennedy Space Center’s storied countdown clock.

Carrying the burden of history, Atlantis pierced the low cloud deck that threatened to scrub this final space shuttle launch, its tail glow lighting a ring beneath the clouds as the craft slipped skyward.

Before liftoff, the clock froze at 31 seconds, leaving the crowd standing for an extra 21 / 2 minutes of will-she-or-won’t-she anticipation as engineers faced a final, minor hiccup. After confirming retraction of a vent arm at the launch pad, mission control gave the go-ahead, sending Atlantis on its way.

Eight and a half minutes later, soaring at 17,000 miles an hour above Earth, Atlantis shut off its main engines for the last time, having achieved orbit for a final 12-day mission, carrying Commander Chris Ferguson, pilot Doug Hurley, and mission specialists Sandra Magnus and Rex Walheim.

“This is mission control Houston,” said liftoff announcer Rob Navias from mission control in Houston. “Atlantis is safely in its preliminary orbit.”

The micro-drama of a tropical storm front almost overtook the larger drama swirling around the end of an era Friday morning as thunderstorms and rain bearing down on Kennedy Space Center almost scrubbed the final space shuttle mission for at least a day. Rain pounded the space center Thursday, leaving viewers sodden and skeptical they would get to catch a glimpse of history.

They did. Hundreds of thousands of space fans gathered on roadsides, causeways, parks and bridges along the Florida’s Space Coast, and some 45,000 VIPs rolled onto the vast space center grounds Friday morning, NASA officials said, including 14 members of Congress and Joint Chiefs of Staff Chairman Adm. Mike Mullen.

According to the Associated Press, by 6 a.m., cars and RVs were packed into almost every available space along U.S. 1 in Titusville, with cameras already trained on the launch pad in the hazy clouds across the Indian River. Many had planted chairs and staked out viewing locations just feet from the water. Some were still cocooned in sleeping bags as the sun rose.

The 12-day mission of Atlantis closes out 30 years of space shuttle flights, leaving NASA without a means to shoot people into space for the first time since 1981.

If not for its status as the final flight, this mundane supply run to the international space station would have drawn little attention. Atlantis will bring up 8,200 pounds of gear to the six-person outpost, install a robotic satellite refueling experiment on the space station, and haul down trash and a broken ammonia pump.

But spaceflight is never routine, as the restless gyrations of the morning made evident. NASA weather officers kept a close eye on a low cloud deck and rain clouds to the north of the launch pad 39A. Before giving the go-ahead, NASA waived one of its weather criteria: a cloudless sky near the KSC emergency landing strip. “Clear to launch Atlantis,” word came down, and the countdown clock — held, as usual, at T-minus nine minutes — rolled.

Atlantis also carries a nod to the 134 shuttle launches that preceded her: mission patches from every flight. Thousands of bookmarks destined for schoolchildren and the first two space-bound iPhones, loaded with an app, SpaceLab, that will help the space station crew track experiments, are also tucked into her lockers.

The four veteran astronauts make up the smallest shuttle crew since 1983. The reason: No backup shuttle exists for a rescue mission if Atlantis suffered damage on launch, like Columbia did in 2003. On that doomed mission, a hole in Columbia’s wing led to its destruction and the deaths of seven astronauts.

For every launch since, NASA has prepped a reserve shuttle for rescue duty. In fact, Atlantis, its external fuel tank and its two solid rocket boosters were originally designated for such duty for the last flight of shuttle Endeavour, which ended in June.

But last year, Congress funded another full, history-making mission for the venerable orbiter.

After Atlantis returns to Earth — scheduled for July 20, the 42nd anniversary of the first Apollo moon landing — robotic tugs from Russia, Japan and the European Space Agency will deliver food, water and other supplies to the station. But none of those craft can carry heavy, bulky loads like the shuttle — such as replacement space station modules — which could be needed if a major segment of the space station failed.

Intense photographic inspection of Atlantis’s shield on Day 2 in orbit will search for nicks, cracks and holes in the shuttle’s 2,000 heat shield tiles. If any appears, the four crew members will shelter on board the international space station, hitching rides back to Earth on Russian Soyuz capsules one by one over the coming year.

“It’s a really tough day if you make a decision not to go and it turns out to be good weather,” launch test director Jeff Spaulding told reporters Thursday. And his words were prophetic.

“There’s an old saying that says it’s better to travel well than to arrive,” Spaulding said. “And I’d have to say after the last 30 years, certainly our program and these shuttles, throughout all of their missions, have traveled very well. And after 135’s landing, I think we can say that we’ve arrived.”

As Atlantis sat ready for her final flight this week, NASA officials ardently pushed a new vision for crewed U.S. spaceflight. Private companies, largely funded by NASA, will deliver astronauts to Earth orbit, while NASA will focus on deep-space missions.

Near the press center, a new NASA capsule — looking much like the Apollo vehicles of the 1960s and ’70s — served as exhibit A for the new ambitions. “It will absolutely fly,” said Wayne Hicks, a NASA engineer on the capsule, once dubbed Orion and now called the Multi-Purpose Crew Vehicle. But the vehicle’s timeline and mission remain uncertain. At a press briefing, vehicle program manager Mark Geyer could not pinpoint when unmanned test flights might occur.

A second capsule, called Dragon and built by the fast-charging company SpaceX, orbited the Earth twice in a test last year. Friday morning below Atlantis lifted off, former NASA astronaut and current SpaceX worker Garrett Reisman said he feels “a huge burden of responsibility” to deliver a manned Dragon vehicle to orbit. Gesturing toward launch pad 39A, he said, “I don’t want this to be the last American rocket to carry people into space for a long, long time. If we fail, it could.”

Despite the forward-looking talk, the mood at Kennedy Space Center was decidedly bittersweet, with former astronauts, VIPs and a gang of Twitterati looking backward.

At 8 a.m., the first shuttle pilot, Bob Crippen, addressed participants of a NASA “Tweetup,” some 200 Twittering space fans invited to promote NASA and its mission. Crippen recounted the first shuttle mission, of Columbia, in April 1981, and the uncertainty he and commander John Young, an Apollo veteran, felt about how the big winged craft would handle. “We were all a little choked up,” said Roxanne Powell-Baxter, a tweeter from Nebraska. “Nobody wants the shuttle to go away.”

The fourth shuttle orbiter to join NASA’s fleet, Atlantis performed nearly every role imagined for the vehicles on her 32 previous missions. She launched robotic probes to Venus and Jupiter; deployed 14 satellites, including NASA’s Compton Gamma Ray observatory; and, in 2009, delivered a crew and robot arm that serviced the Hubble Space Telescope for a fifth and final time in a feat of delicate orbital choreography.

Atlantis also laid the path for international cooperation in space in 1995, flying the first of her seven missions to the Russian Mir space station. By docking with the station, testing a new airlock and working with Russian flight controllers, the diplomatic missions laid the groundwork for construction of the $100 billion international space station. Atlantis starred in that 13-year saga, too, delivering the Destiny laboratory in 2001, the largest U.S. module and the nerve center of the station. Later that year, Atlantis flew up the Quest airlock, giving station astronauts egress even with no shuttle docked.

That impressive legacy behind her, there’s no work left for Atlantis now. In 2004, after the Columbia disaster, President George W. Bush announced the retirement of the three surviving shuttle orbiters after completion of the ISS. And so Atlantis will live out her days as a retiree, tethered to the ground at Kennedy Space Center visitor’s complex, just a few miles from the launch pad that sent her on so many unearthly journeys.