Flight Engineers Chris Cassidy of NASA and Luca Parmitano of the European Space Agency began the spacewalk at 8:02 a.m. EDT to repair several station systems and conduct preliminary tasks ahead of the arrival of the Russian Multipurpose Laboratory Module later this year.
Cassidy routed power cables to support the addition of the new module, known as Nauka, which will serve as a research facility, docking port and airlock for future Russian spacewalks and will replace the Pirs docking compartment, NASA said.
Cassidy had completed five spacewalks totaling 29 hours, 42 minutes, while Parmitano was making his first spacewalk.
The two astronauts are scheduled to head back out of the Quest airlock on July 16 for another spacewalk to complete the work preparing for the Russian module.
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