July 24, 2009

Astronauts swap old batteries for new

Astronauts Chris Cassidy and Tom Marshburn Friday replaced the first of four 375-pound batteries in a spacewalk that could take nearly eight hours, NASA said.

The replacement mission was cut short Wednesday after carbon dioxide levels rose in Cassidy's suit. The lithium hydroxide canister that scrubs carbon dioxide from the suit was replaced for Friday's walk, NASA officials said in a release.

The astronauts are replacing four Port 6 truss batteries with batteries designed to last more than six years and 38,000 charges. Each new battery measures 40 inches by 36 inches by 18 inches and weighs 375 pounds.

The International Space Station is powered by a photovoltaic system that gathers solar power and stores it in the Port 6 batteries.

The astronauts aboard the station were awakened Friday at 5:03 a.m. EDT by Pink Floyd's song Wish You Were Here.