"Floating on the shoulders of giants," shuttle astronauts Mike Fincke and Greg Chamitoff completed the fourth and final spacewalk of Endeavour's STS-134 mission, the last scheduled extravehicular activity (EVA) of the 30-year space shuttle program.
During the 7 hour and 24 minute spacewalk, Fincke and Chamitoff added Endeavour's inspection boom to the station to extend its own arm's reach should it be needed in the future. The final U.S.-delivered component to be attached to the orbiting complex, the space station's assembly is now deemed to be complete.
Mike Fincke and Greg Chamitoff working on installing the boom on the station.
The spacewalkers outfitted the 50-foot boom with a new attach point for station use and then released fasteners on a spare arm for the Canadian multi-arm robot Dextre, as well as photographed experiments mounted on a payload platform installed by Endeavour earlier during the mission.
Coming back inside, Fincke and Chamitoff began repressurization of the station's
Quest airlock at 6:39 a.m. CDT on Friday, marking the official end of final space shuttle crew-performed spacewalk.
A photo worth a thousand hours
Just before returning inside, Chamitoff took a few minutes to photograph the space station's sprawling modules from atop the ExPRESS Logistics Carrier-3 mounted above the complex's truss structure.
Greg Chamitoff's wide-angle photo taken from atop the station. Click to enlarge.
"At this time, now that we are almost done here, I wanted to say a few words," said Chamitoff. "This is the last flight of space shuttle Endeavour but it is also the last spacewalk by shuttle crew members for station assembly. It is kind of fitting that Endeavour is here, because Endeavour was the first shuttle to begin construction for station and so it is fitting that she's here for the last mission to finish assembly."
"During this EVA, we tallied altogether collectively over a thousand hours of spacewalks as part of station assembly. Mike and I have the honor here to share this last spacewalk and of course, with all the folks working on the ground, thousands of people who helped build this, working in the shuttle and station programs. We are floating here on the shoulders of giants."
"This space station is a pinnacle of human achievement and international cooperation. Twelve years of building and 15 countries and now it's the brightest star in the sky and hopefully the doorstep to our future."
"So congratulations everybody on assembly complete," said Chamitoff.
A spacewalk for the history books
Chamitoff and Fincke logged the 1,000th hour spacewalking in support of International Space Station assembly and maintenance at 4:02 a.m., four hours and 47 minutes into the EVA. Spread over 159 shuttle and station spacewalks performed since construction began in 1998, the total time at the end of today's EVA was 1,002 hours and 37 minutes dedicated to the space station.
It was the 118th spacewalk based out of ISS airlocks and the 248th EVA by U.S. astronauts.
Today's excursion was the second for Chamitoff, who has now logged 13 hours and 43 minutes working in outer space. It was the ninth spacewalk for Fincke, who has a total of 48 hours and 37 minutes, ranking him no. 6 on the all-time list for time spent on EVAs.
Later on Friday around 7 p.m., Fincke will set another record, surpassing chief astronaut Peggy Whitson's 376 days in space to become the U.S. astronaut with the most time on-orbit.
This spacewalk was the last by shuttle astronauts. Although STS-134 is the penultimate mission for the 30-year shuttle program, the spacewalk scheduled during the last mission, STS-135, will be conducted by space station crew members.
The first space shuttle-based spacewalk came in April 1983 during space shuttle Challenger's STS-6 mission. Astronauts Story Musgrave and Don Peterson spent 3 hours and 54 minutes during that first shuttle EVA.
In the 28 years since, space shuttle crew members have performed 164 spacewalks to rescue and repair satellites, service the Hubble Telescope and build the International Space Station.
In total, spacewalking shuttle astronauts accumulated 536 hours and 10 minutes working outside their orbiters.