Cosmonauts return to airlock to conclude marathon spacewalk Cosmonauts Fyodor Yurchikhin and Alexander Misurkin returned to the safety of the International Space Station's Pirs airlock compartment Friday after a trouble-free spacewalk, setting a new Russian endurance record with a seven-hour 29-minute excursion. The cosmonauts ran ahead of schedule most of the day, successfully unreeling and routing two long power lines and an ethernet cable along the outside of the Zarya storage module that will be connected to the new Nauka laboratory after its arrival next year. Misurkin also mounted a space exposure experiment pallet on a handrail outside the upper Poisk module. The cosmonauts extended a telescoping space crane early on to help move large cable reels from Pirs to Zarya. They originally planned to leave the Strela 1 boom extended, but flight controllers opted to lengthen the spacewalk to give the cosmonauts time to retract it. The spacewalk began at 10:36 a.m. EDT (GMT-4; time revised by Russian mission control), and ended at 6:05 p.m. when the Pirs airlock hatch was closed. Raw video: Astronauts spacewalk The seven-hour 29-minute duration set a new Russian spacewalk record, eclipsing the old mark of seven hours and 16 minutes set by two cosmonauts outside the Mir space station in July 1990. Two NASA astronauts hold the record for longest spacewalk ever conducted, a marathon eight-hour 56-minute excursion in 2001. Today's EVA ("extra vehicular activity") was the 172nd devoted to station assembly and maintenance since construction began in 1998, the sixth so far this year, the seventh for Yurchikhin and the second for Misurkin. Today's EVA pushed Yurchikhin's total time outside to 45 hours and 55 minutes, moving him up to 12th on the list of most experienced spacewalkers. As it now stands, 112 astronauts and cosmonauts representing nine nations have logged 1,082 hours and 51 minutes of ISS EVA time -- 45.1 days -- building and servicing the space station. The next major assembly task will be attachment of the Nauka -- "science" -- multi-purpose laboratory module (MLM). The Russians originally planned to launch the MLM aboard a Proton rocket at the end of the year, but officials say the flight is expected to slip several months into the spring of 2014. Spacewalk aborted During the past several spacewalks, astronauts and cosmonauts have been installing cables and attachment fittings needed to route power and data to and from the new module, which will replace the Pirs airlock and docking compartment. The Russians eventually plan to launch a multi-hatch node that will be attached to Nauka's Earth-facing end, providing additional ports and the attachment point for a Russian solar power module that will extend to the right side of the space station. Yurchikhin and Misurkin plan to venture back outside next Thursday to install a telescope mounting platform and to remove docking components from Pirs.