Watch: NASA astronauts perform spacewalk to conduct maintenance on ISS

HOUSTON – Two NASA astronauts are performing a spacewalk Wednesday outside the International Space Station.

NASA says Expedition 55 flight engineers Andrew Feustel and Ricky Arnold will perform maintenance work on the ISS, which includes moving a Pump Flow Control Subassembly (PFCS) from a spare parts platform on the station’s truss “backbone” to the Special Purpose Dexterous Manipulator (Dextre) robotic arm.

NASA says the PFCS drives and controls the flow of ammonia through the exterior portions of the station’s cooling system.

Feustel and Arnold will also replace a camera system on the Destiny Laboratory and a communications receiver.

Fuestel and Arnold arrived at the ISS on March 23 after launching to the station on March 21 on board a Soyuz MS-08 spacecraft with Russian cosmonaut Oleg Artemyev.

This is Fuestel’s 8th spacewalk and Arnold’s 4th. This also be the 50th spacewalk originating from the station’s Quest airlock.

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