NASA says two U.S. crewmembers of the International Space Station (ISS) will make a "contingency" spacewalk on May 23 to replace a computer system that failed on May 20.
The space agency on May 21 said ISS managers gave the approval for two U.S. astronauts make the spacewalk, which is expected to last two hours.
NASA said the multiplexer-demultiplexer (MDM) data-relay box that failed was one of “two fully redundant systems” that control radiators, solar arrays, cooling loops and other hardware.
The cause of the MDM failure was not yet known, NASA said.
Commander Peggy Whitson and Flight Engineer Jack Fischer, both of NASA, will conduct the mission, the sixth spacewalk this year from the ISS, it said. Fischer will also install a pair of wireless communications antenna.
The current ISS contingent has five-member crewmembers, two from the United States, two from Russia, and one from France.
Crewmembers carry out biology, life science, materials science, and physics experiments, along with astronomical observations and Earth remote sensing.
The station is jointly owned by 15 nations and has been continuously staffed since 2000.