NASA to attempt California touchdown

Bad weather scuppered two efforts to land the space shuttle Endeavour in Florida Sunday, and NASA officials said they plan to try to touch the spacecraft down later in the day at California's Edwards Air Base.

NASA television announced that two landing attempts had been delayed because of inclement weather conditions at the shuttle landing facility at Cape Canaveral in Florida.

"A front is continuing to move through northern Florida and is causing some thunderstorms to build up in the southern portion of Florida," NASA television reported.

Endeavour must land by Tuesday because by then it will have almost exhausted its supplies of oxygen and water as well as its hydrogen batteries, which supply electricity.

NASA never waits until the last minute to bring a craft back to Earth.

Just after the Endeavour undocked Friday from the International Space Station (ISS), a final inspection of its nose cap and wing leading edge panels was conducted by camera and laser device.

Cain said that after completing the damage assessment, his team had cleared Endeavour's thermal shield for a safe entry and landing.

Flight director Brian Lunney at Johnson Space Center in Houston, Texas, said Saturday that the flight control system "checked out, no anomalies ... That system is ready to support entry."

Lunney said the Endeavour had two landing attempts at the Kennedy Space Center (KSC) Sunday, at 1819 GMT and 1954 GMT, with a third window at Edwards in California's Mojave desert at 2125 GMT.

"We will be willing to go land on Sunday at Edwards if we look at the forecast and determine Monday is not worth waiting for in terms of going to KSC," he added.

If Endeavour returns as scheduled on Sunday, it will have spent 16 days in orbit, 12 of them docked at the ISS.

During their mission Endeavour astronauts took four space walks to successfully repair a jammed joint of one of three rotating solar panels that harvest energy for the orbiting ISS.

Technical problems with a new piece of equipment that recycles waste water caused NASA to extend the mission by a day.

The 250-million-dollar device was an essential part of the shuttle mission to double the station's accommodation capacity.

Crew members ran three successful cycles on the unit, designed to process urine, perspiration and bath water into drinkable water.

Once up and running, the unit will be able to recycle the station's 6.8 tonnes of waste water produced each year, and make it no longer necessary to regularly ferry vast quantities of water to the space station.

Samples of the drinking water produced by the machine are being brought back to Earth for analysis.

The Endeavour crew also delivered two new sleeping quarters, two ovens and a refrigerator that double the living space on the ISS to allow its crew to increase from three to six.

The Endeavour mission is the last by a US space shuttle in 2008. The next shuttle flight is scheduled for February, with another mission to continue building the space station.

The ISS should be finished in 2010, also the target date for the retirement of the US fleet of three space shuttles.