U.S., European Astronauts Resume Scheduled Space Station Spacewalks

U.S. and European astronauts Reid Wiseman and Alexander Gerst transferred a bulky failed thermal control system pump module from a temporary storage fixture on the International Space Station to a protective storage platform near the U.S. airlock during a long spacewalk Tuesday.

The excursion, which got underway at 8:30 a.m., EDT, was the first scheduled NASA-led spacewalk since July 2013, when cooling system water leaked into the helmet of the NASA spacesuit worn by European Space Agency astronaut Luca Parmitano. The incident prompted a suspension of all but emergency spacewalk repairs, while NASA made modifications to the garments and procedural changes.

European Space Agency astronaut Alexander Gerst, lower left, worked from the tip of the space station's robot arm to transfer a failed pump module.  NASA astronaut Reid Wiseman, upper center, assisted. NASA

During Tuesday's spacewalk, Gerst secured himself to the tip of the station's 58-foot-long robot arm to swing out from and under the central ISS solar power truss with the 780 pound pump module. The robot arm, controlled from inside the station by NASA astronaut Barry Wilmore, moved him to a new storage platform near the U.S. airlock, which could become the staging site for a future pump module repair.

"You should see my view right now." teased Gerst, as he began a swing out from the station with a rising sun just beginning to pierce the darkness. "It's just beautiful, amazing."

A flow control valve in the module failed last December, prompting two emergency spacewalks within days to replace it.

Wilmore is to join Wiseman for a spacewalk on Oct. 15 to replace an external voltage regulator that failed in May. The fix will restore an ISS power channel -- one of eight in all -- that was taken off line in response.

NASA plans a series of spacewalks extending into 2015 to prepare docking ports for Commercial Crew Program capsules in the final stages of development by Boeing and SpaceX. The extensive reconfiguration will also prepare the station for the arrival of Bigelow Aerospace's prototype Expandable Activity Module.