Atlantis and its four crew members blasted off into space on Friday, marking the final mission of NASA's three-decade-old shuttle program.
The shuttle took off just behind schedule at 11:29 ET for the eight-minute flight into orbit. It is the last time a shuttle will travel to space before the program is retired.
"The space shuttle spreads its wings one final time for the start of a sentimental journey into history," said a NASA observer from the Kennedy Space Center as the shuttle blasted off smoothly.
However, there were some concerns that the historic flight would have to be delayed at the last minute.
The countdown clock had paused with 31 seconds remaining before launch, as technicians appeared to have last-minute concerns related to a retractor sensor. After about a one-minute delay, however, the countdown resumed and the engines fired up as the massive rocket and shuttle lifted off.
"I bet the crew can't believe it since it looked so unlikely yesterday. They probably feel like they came to Florida, squealed the tires and left, and it's great to see it safely in orbit. It's a wonderful way to close out the space shuttle part of the world space program," Canadian astronaut Chris Hadfield said.
If everything goes as planned it will take about two days for the shuttle to reach the International Space Station.
Weather not a factor
Astronauts had donned flight suits, boarded the shuttle and prepared for blast-off Friday morning even as the stormy weather threatened to derail the historic final launch.
As of 9 a.m. ET, forecasters were calling for a 70 per cent chance of thunderstorms or rain, either one of which would shut down the launch. But as the morning went on the weather cleared and flight controllers decided to go ahead with the flight.
Flight commander Christopher Ferguson appeared to be hoping for the best on Friday morning. He jokingly called on the crowd for more applause as he approached the spacecraft and gave a thumbs up as he was strapped in.
Despite the foreboding weather, technicians had begun fuelling the shuttle overnight in hopes the flight could go ahead as planned at 11:26 a.m. ET.
An estimated 750,000 people were expected to gather in Cape Canaveral and the surrounding towns to watch the final launch before the 30-year-old program is completed.
The crowds were expected to be similar in size to those that gathered when the Apollo moon missions were launched.
By Wednesday, space junkies had already staked their claim on prime viewing spots in the area.
On Friday, VIPs including four members of the Kennedy family, the first shuttle pilot Robert Crippen, and singers Jimmy Buffet and Gloria Estefan had made their way to Cape Canaveral for the launch.
Hadfield, who flew to space on Atlantis 16 years ago, said he felt a surge of emotion while driving to the launch site on Friday morning seeing the shuttle lit up and ready for take-off.
"It took me right back to driving out to the pad, wearing my pressure suit, as everyone else was moving away from that huge rocket...waiting for it to take us away from the Earth and it was an unexpected rush of emotion for me," he said.
Beginning of the end
The shuttle program began in 1981 with the launch of Columbia. Since then, 135 shuttle missions have been launched. Atlantis itself will have flown 35 missions by the time it heads into retirement, joining Discovery and Endeavour.
The shuttle is loaded up with a year's worth of supplies for the International Space Station, weighing about 8,000 pounds.
U.S. President Barack Obama called for the end of the shuttle program last year, tasking NASA with focusing its efforts on sending astronauts to Mars and to asteroids instead.
Russia to supply space station
It will now be a minimum of three years before astronauts once again launch from U.S. soil. In the meantime, Russian Soyuz rockets will carry astronauts and supplies to the ISS, including Chris Hadfield, who will spend six months at the space station in 2012.
For part of his lengthy stay Hadfield will command the orbiting ISS, becoming the first Canadian to do so.
Discovery Channel host Jay Ingram said there will likely be a lull in activity for NASA for the next five or so years.
‘There's going to be a bit of a pause for sure," he said, adding that new spacecraft for carrying humans into space are in development.
