In a view through a porthole, cosmonauts Oleg Kotov and Sergey Ryazanskiy can be seen working to mount a high-resolution camera to a mounting platform on the International Space Station's Zvezda command module. NASA TV

Last Updated Dec 27, 2013 5:42 PM EST

After running into problems hooking up two commercial Earth-viewing cameras, cosmonauts Oleg Kotov and Sergey Ryazanskiy reluctantly brought the high-tech cameras back into the Pirs airlock moduleFriday, closed the hatch and ended a marathon spacewalk, setting a new Russian record in an otherwise disappointing excursion.

The UrtheCast camera is designed to be mounted on the outside of the International Space Station.

UrtheCast

"We're back home," one of the cosmonauts radioed.

"Thank you for all your hard work, and we're so sorry that it turned out this way," a flight controller radioed in translated remarks.

The spacewalk began at8 a.m.and ended at4:07 p.m. EST(GMT-5). The eight-hour seven-minute outing set a new Russian endurance record and beat the previous mark of seven-hours and 29 minutes set in August by cosmonauts Fyodor Yurchikhin and Alexander Misurkin. The U.S. spacewalk record stands at eight hours and 56 minutes.

The primary objective of Friday's outing was to install two cameras for Vancouver-based UrtheCast, a high-resolution telescope mounted on an aiming platform and a fixed medium-resolution camera. Both are required for a long-awaited commercial project to beam down near realtime high-definition Earth views, including a free internet stream as well as focused observations for paying customers.

Kotov and Ryazanskiy successfully installed the cameras and plugged them into the station's power and data circuits. But Russian flight controllers did not receive telemetry, prompting the cosmonauts to retrace their steps and inspect each electrical connector.

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