What happened on the spacewalk
Two Expedition 75 crew members, NASA's Anil Menon and Joshua Kutryk of the Canadian Space Agency, installed and deployed an upgraded roll-out solar array on Thursday, Oct. 29, according to Space. The spacewalk ended at 3:08 p.m. EDT after 7 hours and 11 minutes. It began and ended in the U.S. Quest airlock, and both astronauts wore NASA EMU spacesuits.
The pair first unbolted the rolled-up array, known as an iROSA, from a temporary stowage platform. The assembly measures about 10 by 2 by 4 feet when stowed. It reached the station earlier this month in the unpressurized trunk of a SpaceX Dragon cargo capsule on the company's 35th ISS resupply mission for NASA.
Menon then secured himself to the end of the Canadarm2 robotic arm and carried the 750-pound array to the station's port side. There, he and Kutryk installed it on the 2A electrical power channel. Kutryk reached the worksite by moving along the station's backbone truss.
How the array unfurled
After the astronauts bolted the iROSA in place, they connected its electrical cables to the station's power system. According to Space, they did this during a night pass because of safety concerns.
The array needed no motor to deploy. The energy stored in its rolled-up carbon composite booms was enough to unroll it to its full length of about 63 feet. "And we see the iROSA deploying now," Mission Control reported, four hours and 23 minutes into the spacewalk.
About 12 minutes later, the array was fully extended. It now covers roughly half of a larger but less capable legacy panel on the P4 truss. With time to spare, Menon and Kutryk began preparing the final iROSA by removing some of the beams holding it on its temporary platform. They also rotated two launch locks used during its delivery on Dragon.
Why the station needs more power
The station's eight original solar arrays are producing less power as they have outlasted their 15-year design life, according to the report. Used alongside the older panels, the iROSAs have raised the station's power supply by 20% to 30%.
That extra power is needed for current and planned operations, Space reported, including the station's safe and controlled deorbit, which is currently scheduled for 2030.
A milestone and a first
Thursday's outing was the 100th U.S. spacewalk from the station without a now-retired space shuttle docked. Overall, it was the 285th spacewalk supporting ISS assembly, maintenance and upgrades. That total includes 66 from the Russian segment and 119 by visiting shuttle crews. The first U.S. spacewalk from the Quest airlock took place on Feb. 20, 2002. Expedition 4 crewmates Carl Walz and Daniel Bursch spent 5 hours and 47 minutes mostly testing Quest's systems and completing "housekeeping chores."
It was Menon's fourth spacewalk and Kutryk's first. Kutryk is the fifth Canadian astronaut to conduct one, and the first Canadian outside the station since David Saint-Jacques in April 2019. Menon has logged 26 hours and 31 minutes of spacewalking during his current stay.
"Being outside, I can say it is always sunny in space," Menon said at the end of the spacewalk. He called the 100th U.S. spacewalk "an incredible milestone," adding, "I think it really signifies how much we have done."
What happens next
Menon and Kutryk are scheduled to make another spacewalk on Nov. 5. They are expected to install the eighth and final iROSA, which would complete the five-year effort to upgrade the station's power supply, according to Space.
