The installation of the IDA means the space station will be able to accommodate various space taxis, including SpaceX and Boeing vehicles. Before now, only Russian vehicles were able to dock with space station.
"We've opened up a new chapter [of] the story of the International Space Station," Williams said. "Congratulations to the entire team." Williams also took a moment to wish a happy birthday to NASA Administrator Charles Bolden, who turned 70 today.
Ahead of schedule, Williams and Rubins packed up their IDA tools and started work on some "get ahead" tasks. They snapped some photos of the new docking port and routed some additional cables for a second IDA, which will be flown up to the space station next year.
PHOTO: Stunning View from the Space Station, Front Row Seat
Due to broken communication with Williams' right ear piece, additional minor "go ahead" tasks were called-off and the two astronauts headed back to the space station's airlock around 1:30 EDT (1730 GMT). They safely returned inside of the space station at 2:02 p.m. EDT (1802 GMT).
On Sept. 1, Williams and Rubins will perform a second 6.5-hour spacewalk to retract one of the station's thermal radiators, among other tasks. Williams will return home Sept. 6 with Russian cosmonauts Oleg Skripochka and Alexey Ovchinin. Williams is set to surpass Scott Kelly's record for the most total cumulative time spent in space by an American, with a total of 534 days.
Follow Samantha Mathewson @Sam_Ashley13. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.
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