Atlantis astronauts complete third and final spacewalk

Two US astronauts completed their final spacewalk yesterday at the International Space Station, replacing batteries before heading home.

Garrett Reisman and Michael Good re-entered the orbiting station's decompression chamber at 1.13 p.m. (1713 GMT) after the Atlantis crew's third spacewalk in five days. Their sortie lasted six hours and 46 minutes.

The pair plugged a new ammonia jumper cable into the orbiting space station's huge framework and installed two new batteries that store energy collected by the station's large solar panels.

Each battery weighs 170 kilograms and measures about the size of a three-foot (one-metre) box. Mr Good and another fellow astronaut swapped out another four batteries during another spacewalk on Wednesday. Batteries usually last five to six years but the ones that were replaced had functioned for nine years. The old batteries will be brought back to Earth aboard Atlantis.

During their spacewalk, the two astronauts also transferred a grapple fixture from the shuttle to the station and reconfigured some tools.

During the 12-day mission, Atlantis and its six-member crew unloaded over 12 tons of equipment, including the communications antenna, power storage batteries and a radiator.

The biggest single element is the five-ton Rassver research module, or MRM-1, which will provide additional storage space and a new docking port for Russian Soyuz and Progress spacecraft.