Live In Orbit: Astronauts Finish Outpost Outfitting

Spacewalking astronauts celebrated the 40th anniversary of the historic Apollo 11 moon-landing with an outfitting excursion outside the International Space Station.

With NASA's shuttle fleet set to retire at the end of next year, Endeavour astronauts Dave Wolf and Tom Marshburn stowed some critical spare parts on a storage platform on the metallic backbone of the complex.

The $100 million station -- the assembly of which is about 85 percent complete -- now is equipped with a spare communications antenna, an extra cooling system pump and another drive system for an outpost rail cart.

"A special day to do this on this 40th anniversary of Apollo," said lead spacewalker Wolf.

"Absolutely," Marshburn replied.

"Houston concurs," Japanese astronaut Aki Hoshide said from NASA's Mission Control Center.

The spacewalk was the 127th carried out since the first two building blocks of the outpost were linked in low Earth orbit. Here are eight NASA screen grabs that show Wolf on the end of the station's 57-foot robot arm during the six-hour, 53-minute spacewalk: