Five men, one woman, and a gold-faced robot with a passing resemblance to the Star Wars character C-3PO went through their final countdown last night, as the world's oldest and most-travelled space shuttle blasted into orbit round the Earth for one last time.
After 150 million miles and a combined total of almost 50 weeks of boldly going, the 26-year-old Discovery lifted off from Kennedy Space Centre at Cape Canaveral in Florida at 4.50pm local time to begin its 39th and final mission.
The start of the 11-day trip to the International Space Station was accompanied by all the usual bells and whistles of a major Nasa launch, from a flag-waving crowd of 40,000 to endless press conferences from the organisation's senior boffins.
But amid the pageantry, there was a hint of sadness: Discovery's last hurrah doesn't just mark the retirement of a craft known to US astronauts as "the champion of the fleet", it also hastens the demise of the shuttle as a means of extra-terrestrial transportation.
The era-defining brand of spacecraft – which was given the go-ahead by Richard Nixon, entered space under Ronald Reagan and outlasted the Cold Wa – is scheduled to be shuffled off into retirement later this year, with the loss of 7,000 jobs.
It is the victim of swingeing budget cuts at Nasa, combined with doubts about safety which stretch back to the Challenger disaster of 1986, and became seriously pressing after 1 February 2003, when Columbia disintegrated during re-entry to the Earth's atmosphere.
Mike Leinbach, the launch director, admitted before lift-off yesterday that it will be "tough" to see Discovery go. "You'll see a lot of people on the runway who will probably choke up some," he said. "It's the end of a 30-year programme we've grown to love and appreciate and feel like we're doing something special for the country and, really, the world."
Once Discovery returns, Nasa will prepare for April's scheduled final journey of Endeavour, the shuttle which is due to include in its crew Mark Kelly, the 47-year-old husband of the wounded Tucson Congresswoman Gabrielle Giffords.
Then, Nasa will formally end the era of the space shuttle on 28 June, when Atlantis begins a 12-day mission to the International Space Station. After that, America will find itself in the embarrassing position of having to cadge lifts for astronauts in spacecraft owned by Russia. Nasa's long-term plans, such as they are, involve private companies providing orbital transport. Given such uncertainty, the demise of Discovery represents a particularly sad moment. It has always been the most loved and trusted of Nasa's fleet. It was chosen for Nasa's symbolically important first missions after the Challenger and Columbia disasters.
This week's final flight has been arranged to ferry 1.75 tons of supplies and spare parts to the International Space Station, most notably a humanoid robot named "Robonaut 2", which has a gold face and stands a little over 3ft tall.
The robot will work alongside human inhabitants of the station. At first, it will carry out mundane tasks, such as cleaning. But engineers hope it will eventually take over more dangerous and complex duties, including space walks.
In one of the more unlikely scientific experiments to be carried out during the trip, researchers from the University of Guelph in Canada will tickle the feet of Discovery's six crew members before take-off and immediately after landing to identify which skin receptors are most influenced by weightlessness.
The mission was originally scheduled to begin in September, but was delayed by problems with the fuel tank and the withdrawal of a crew member who crashed his bicycle.
Though originally conceived in the 1970s as an economical alternative to rockets (they could complete multiple missions, while each rocket could only fly once) they proved far less reliable, and more expensive than expected. When the shuttle programme was launched, its architects envisioned that American astronauts would fly a mission a week, launching satellites and defence systems, and building vast space stations.
In the event, Nasa never managed more than nine or 10 shuttle flights a year. Thousands of highly trained engineers were needed to maintain each craft in the fleet, at a huge expense. Then there were the two disasters, in which 14 people died.
Discovery's future probably now lies as a museum piece: negotiations are under way for it to be donated to the Smithsonian. "There is nothing better than a real artefact, and Discovery has been an icon of human space flight for 30 years," said Valerie Neal, curator of the institution's National Air & Space Museum, who spoke to The Independent from the launch site yesterday.
Up, up and away no more
August 1984 After four years in the making, Discovery is launched on its maiden voyage to deploy three communications satellites.
April 1990 The Hubble Space Telescope, one of the most important astronomical tools ever made, is carried and launched into orbit by Discovery.
February 1994 Discovery becomes the first American space shuttle to host a Russian cosmonaut, Sergei Krikalev.
February 1995 The shuttle becomes the first American spacecraft to dock with the Russian space station Mir. This mission also sees Eileen Collins become the first female space shuttle pilot.
February 2011 After performing 38 voyages, travelling 230 million kilometres and orbiting the earth 5,628 times, Discovery launches for the last time.