Endeavour must wait for good weather

Thick clouds over the Kennedy Space Center landing site in Florida thwarted two landing attempts, and mission control was forced to delay the return for at least 24 hours.

"It's not a good day to bring Endeavour home," a spokesman said.

On Monday, Endeavour undocked from the International Space Station (ISS) to bring to Earth the Expedition Five crew - Valery Korzun, Peggy Whitson and Sergei Treschev. They had been living aboard the platform for six months.

Three spacewalks

Staying behind is Expedition Six - Ken Bowersox, Nikolai Budarin and Don Pettit. They will now live and work in space until at least March next year.

Plumbing work 390 km above the Earth

Earlier this week, the Endeavour crew successfully completed its mission to help extend the orbiting platform.

It took two astronauts - John Herrington and Michael Lopez-Alegria - three spacewalks to fix a new 13.5-metre-long (45 feet) hi-tech beam to the station's growing structure.

During the third walk, they had to free a two-tonne, $190m trolley car that had become stuck on the tracks that run along the top of the truss.

The Endeavour crew also raised the altitude of the space station.

The shuttle commander Jim Wetherbee made a series of firings of the orbiter's thrusters to take the platform about 4.5 kilometres (2.8 miles) further away from the Earth.

The ISS is now almost 10.5 km (6.5 miles) higher than it was when the shuttle docked on 25 November. Its average altitude is 397 km (247 miles).