Image caption Just four astronauts will fly on the final space shuttle mission. Atlantis lifts off on Friday

The four US astronauts who will crew the last ever space shuttle mission have arrived in Florida.

The three men and one woman will launch in the Atlantis orbiter on Friday from the Kennedy Space Center.

Bumper crowds are expected on the Space Coast to watch the 1126 local time (1526 GMT) lift-off.

The US space agency (Nasa) is retiring its shuttles to make way for crew and cargo transportation services that will be operated by private companies.

Atlantis will be hauling more than 3.5 tonnes (8,000lb) of supplies to the International Space Station (ISS).

This load includes a year's worth of food. It should give Nasa some room to play with if the new commercial players have difficulty meeting their contractual obligations.

The four Atlantis astronauts - Commander Chris Ferguson, Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim - flew into Kennedy from their training base in Houston, Texas.

As it was Independence Day here in the US, they had no hesitation in waving the Stars and Stripes for the photographers.

"This is a day that is decidedly American," said Commander Ferguson. "We have an eventful 12-day mission ahead of us… and when it's all over I think I can speak for everyone when I say we'll be very proud to put the right-hand book-end on the space shuttle programme."

Pilot Hurley added: "We want to thank the team that processed the Atlantis shuttle for her last flight. We just want to honour the entire Kennedy team that has worked on these magnificent machines these last 30-plus years."

The 8 July ascent will be the 135th shuttle launch and the 33rd of Atlantis.

In total, 355 individuals will have flown 852 times on those 135 missions since the very first shuttle flight on 12 April, 1981.

The five orbiters used over the course of the programme have flown 864,401,219km (537,114,016 miles) - a distance roughly similar to travelling from the Earth to the Sun and back three times.

Atlantis will add a further 6.5 million km (four million miles) to that total.

Discovery was the first ship to begin the run-down with a final flight in March, followed by Endeavour which landed one last time on 1 June.

The vehicles are all being retired to museums. Atlantis will end its days at the Kennedy Space Center visitor complex.

Jonathan.Amos-INTERNET@bbc.co.uk