Veteran spaceman David Wolf and rookie Timothy Kopra got straight to work as they floated out the hatch, 220 miles above the Earth. But their voices could hardly be understood at times because of loud static, caused by their helmet microphones.
"Dave, you're unreadable," astronaut Christopher Cassidy called from inside, nearly two hours into the spacewalk. He apologized to flight controllers for the "ratty comm," explaining that the spacewalkers were trying to fix the problem.
With Apollo 11 on the minds of many back on Earth, NASA noted that Saturday's spacewalk was the 201st by Americans since those first steps on the moon by Neil Armstrong and Buzz Aldrin 40 years ago this Monday.
Remaining inside the linked shuttle and international space station were 11 astronauts, a full house. The station population swelled to a record 13 when Endeavour arrived Friday for a 1½-week stay.
The two crews teamed up for Saturday's big event, the attachment of a large veranda to Japan's $1 billion lab for outdoor experiments. It's the third and final section of the lab, the largest one at the space station, and flew up aboard Endeavour.
The work involved extensive robotics with both the shuttle and station arms, as well as a hands-on effort by the spacewalkers. Wolf prepped the lab - named Kibo, Japanese for "hope" - by removing an insulating cover and then tossing it overboard. Meanwhile, Kopra got the porch ready for release from Endeavour's cargo bay. The porch attachment was going to be performed by the station's powerful robot arm.
"It's going to be something," Wolf said earlier in the day. "It's a heck of a day of teamwork between robots and people in space and all over the world."
As the day got under way, Mission Control had both good and bad news for the 13 spacefarers.
The good: Endeavour looks to be in fine shape for re-entry at the end of the month, although a review of shuttle photos and other data continues.
The bad: The astronauts were informed of former TV news anchorman Walter Cronkite's death. Mission Control relayed statements by Armstrong and NASA's new chief, ex-astronaut Charles Bolden, both of whom noted Cronkite's passion for human space exploration.
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