Anil Menon, riding the space station robot arm, moves the folded, rolled-up IROSA assembly to its installation point at the Starboard end of the space station truss. Image: NASA.
Spacewalking astronauts Joshua Kutryk and Anil Menon unfurled the last of eight new solar arrays outside the International Space Station Thursday, working through an unexpected power snag to complete a five-year upgrade designed to keep the orbiting laboratory running through its retirement in 2030.
The final International Space Station Roll-Out Solar Array, or IROSA, unrolled at the far starboard end of the station’s main truss at about 3:05 p.m. EST (2005 UTC), roughly six and a half hours into the spacewalk. That came only after flight controllers in Houston spotted lower-than-expected electrical current from the freshly connected array and held the deployment through another trip around the planet so Kutryk could inspect a power connector in the darkness of orbital night.
“Josh, deployment is complete,” Mission Control radioed Kutryk after the previously rolled-up array reached its full length of 63 feet.
According to NASA, the eight IROSAs will raise the station’s available power by up to 30 percent, supporting the outpost through its final years, including what the agency says will be its “safe and controlled deorbit.”
Kutryk, 44, and Menon, 50, switched their spacesuits to battery power at 8:36 a.m. EST (1336 UTC) to begin the 286th spacewalk devoted to station assembly, maintenance and upgrades, and began repressurizing the Quest airlock at 3:35 p.m. EST (2035 UTC), formally ending a 6-hour, 59-minute spacewalk.
It was the ninth spacewalk of 2026 and the sixth by members of the station’s Expedition 75 crew, NASA commentator Joseph Zakrzewski said. It was Menon’s fifth spacewalk, bringing his total time outside to 33 hours and 30 minutes, and the second for Kutryk, a Canadian Space Agency astronaut who logged 14 hours and 10 minutes across his pair of IROSA installation spacewalks.
Kutryk led Thursday’s outing with the call sign ‘EV1’, wearing the red-striped suit, a week after he and Menon installed the seventh IROSA during a seven-hour, 11-minute spacewalk Oct. 29.
The final array was arguably the hardest to reach. Its mounting point on the station’s outermost starboard truss segment sits beyond the reach of Canadarm2, the station’s Canadian-built robotic arm, so the spacewalkers had to close the last stretch by hand.
After Kutryk released the last of the bolts holding the folded array, about 10 feet long and roughly 750 pounds, to the carrier it launched on, Menon locked his boots into a foot restraint at the end of the arm and took it in hand. NASA astronauts Luke Delaney and Jessica Watkins, working with flight controllers, then flew Menon and the array down the truss in a careful series of yaw and roll maneuvers.
At about 10:23 a.m. EST (1523 UTC), Menon handed the array to Kutryk, who was waiting in a foot restraint of his own near the installation site. Menon then climbed off the arm, set up another foot restraint and, about 40 minutes later, took the array back from Kutryk to guide it into place.
“Another handoff complete,” Zakrzewski said as Menon took control of the array during an orbital night pass. Flight controllers said the pair was about 15 minutes ahead of the timeline.
By this point, Menon was on familiar ground. He and NASA astronaut Jessica Meir bolted the triangular mounting bracket for this array, known as a modification kit, onto the old solar wing’s base during an Aug. 6 spacewalk.
After some wiggling and a slight yaw adjustment to line up an alignment guide, the spacewalkers seated the IROSA on the bracket and, about 15 minutes later, swung it open to its full 20-foot width.
The power cables had to wait for darkness. Because the station’s existing solar wing and its cabling are live whenever they’re in sunlight, the crew can only connect the new array’s power cables during the roughly 45 minutes of each 90-minute orbit when the station passes through Earth’s shadow.
The pair finished mating the cables at about 12:36 p.m. EST (1736 UTC), well within the darkness window, but then came the snag. About four and a half hours into the spacewalk, the ground relayed that the new array was delivering only about half the current engineers expected.
Because the cables could only be safely handled again in darkness, flight controllers reshuffled the plan. Kutryk and Menon moved up their cleanup tasks, stowing the foot restraints and the robotic arm hardware, while waiting for the next orbital night. Mission Control told them the extra time would stretch the spacewalk to about seven hours, which their spacesuits could support.
When the station slipped back into Earth’s shadow, Kutryk returned to the worksite, disconnected one of the cable connections, inspected both ends and plugged it back in, confirming it was firmly seated.
“Certainly looks like a good solid mate now,” he said.
After the station returned to daylight, flight controllers reported “good currents” and cleared the crew to deploy the array. NASA did not immediately say what caused the initially low readings.
Kutryk then released the final restraint bolts, and the solar panels began unfurling on their own, driven by strain energy stored in carbon-fiber composite booms. The process took about 10 minutes, Zakrzewski said.
Each IROSA generates about 8 kilowatts of power, Zakrzewski said, compared with 19 kilowatts for each of the station’s original wings when they were new.
Space shuttles delivered those original solar arrays between 2000 and 2009. They were designed to last 15 years, and their output has gradually declined. Rather than replace them, NASA opted to mount the smaller, more efficient roll-out arrays in front of the old wings, partly shading them while the wings’ exposed portions keep producing power.
The first IROSA unrolled in June 2021. Six arrays were in place by June 2023, and NASA ordered the final pair later that summer. Those two arrays launched to the station Oct. 13 atop a Falcon 9 rocket.
Hehn led Thursday’s spacewalk from Mission Control in Houston, alongside Greg Whitney, who led the Oct. 29 outing. NASA astronaut Nichole Stilwell served as spacewalk communicator.
With the power upgrade finished, NASA’s next planned U.S. spacewalks are targeted for early January to upgrade the Alpha Magnetic Spectrometer, a cosmic-ray detector mounted on the station’s truss, Gaurang Patel, operations integration manager for NASA’s Low Earth Orbit Program, said at an Oct. 20 briefing.
After reentering the ISS’ Quest airlock, Kutryk reflected on his second outing in low Earth orbit — one that required some on-the-fly coordination with Mission Control to pull off.
“So impressive to see the team respond and get us to where we needed to be, despite the challenges that we encountered along the way,” Kutryk said, addressing Mission Control. “Like I said last time, you are masters of your craft.”
Menon touted the importance of this final, and successful, IROSA spacewalk.
“Today marks the completion of not just one solar array, but over 15 years of development efforts to deploy eight arrays and provide power that will allow the station to continue to be a staircase to the moon and eventually Mars,” Menon said. “Privilege of a lifetime. I’ll never forget it.”

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