The space shuttle Endeavour has returned to Earth after an eventful mission to repair parts of the International Space Station (ISS).

The shuttle's landing site was switched from Florida to Edwards Air Force Base in California due to bad weather. The shuttle touched down safely at around 1325 local time (2125GMT). The mission had been extended by a day because Nasa wanted the shuttle's crew to make repairs to a machine which makes drinking water from urine

Lost tool bag

The shuttle, with a crew of seven, was piloted by Commander Christopher Ferguson. "Welcome back. That was a great way to finish a fantastic flight," Mission Control radioed. "And we're happy to be here in California," Commander Ferguson replied. Earlier on Sunday a Russian space vessel docked with the ISS, delivering food, clothes and Christmas presents. Russian flight engineer Yury Lonchakov remotely guided the Progress spaceship to a docking port after an automated system failed. Endeavour's mission saw the shuttle and its crew spend 16 days in space. The equipment to provide drinking water from astronauts' urine had failed several times since it was delivered two weeks ago. During four spacewalks, the crew serviced the station's two Solar Alpha Rotary Joints, which allow its solar arrays to track the sun, and installed new hardware that will support future assembly missions.

The work was slower than expected because astronaut Heide Stefanyshyn-Piper lost her tool bag during the first spacewalk. Inside the station, ISS commander Mike Fincke supervised work on the malfunctioning water regeneration system which distils, filters, ionises and oxidises wastewater - including urine - into fresh water. Earlier, the system's centrifuge - needed to separate solid particles from liquid as part of the distillation process - became unbalanced as it spun and shut down before the intended four-hour cycle was complete. The equipment to provide drinking water from astronauts' urine had failed several times since it was delivered two weeks ago. During four spacewalks, the crew serviced the station's two Solar Alpha Rotary Joints, which allow its solar arrays to track the sun, and installed new hardware that will support future assembly missions.

The work was slower than expected because astronaut Heide Stefanyshyn-Piper lost her tool bag during the first spacewalk. Inside the station, ISS commander Mike Fincke supervised work on the malfunctioning water regeneration system which distils, filters, ionises and oxidises wastewater - including urine - into fresh water. Earlier, the system's centrifuge - needed to separate solid particles from liquid as part of the distillation process - became unbalanced as it spun and shut down before the intended four-hour cycle was complete. News source