The space shuttle Atlantis thundered into the sky over Kennedy Space Centre on Monday carrying six crew members on a mission to the International Space Station.
The mission is part of the US space agency's efforts to stock up the ISS reserves as the shuttle programme enters its expected final year in 2010. After this week's mission there are just five more flights scheduled.
The all-American crew wearing orange jumpsuits were earlier strapped into their seats by ground crew after leaving their quarters to cheers and applause from the gathered crowd. They will spend 11 days in space.
Thousands of visitors watched the launch along with a group of NASA-selected users of the micro-blogging website Twitter, who were giving their impressions of the launch online in real time.
David Rosen, 31 from New York, who said he has long loved space, was among the Tweeters and hoped to provide a first hand account to his 190 followers.
He said he hoped to convey the awe of experiencing a launch firsthand. "They'll feel it a lot more because they know me," he said of those reading his Tweets.
Atlantis is to dock Wednesday with the space station, which orbits 350 km above earth.
The shuttle will deliver two platforms with 12,360 kg of spare parts, which will be installed on the outside of the station.
As the first of several flights devoted largely to delivering spare parts, this mission is carrying the highest-priority items.
The so-called Express Logistics Carriers contain a variety of crucial parts, such as: gyroscopes that help keep the ISS at the proper altitude in space; an extra hand for the station's robotic arm; a gas tank for providing oxygen to the airlock during spacewalks; and parts for the station's cooling system.
Astronauts will also bring along assorted colourful personal items for the ride, including a scarf worn by aviation pioneer Amelia Earhart. The scarf has a personal connection for astronaut Randolph Bresnick, whose father served as a photographer to Earhart before her plane was lost over the Pacific during an intended round-the-world
flight in 1937.