The International Space Station’s solar-power upgrade reached its seventh installation on Oct. 29. NASA astronaut Anil Menon and Canadian Space Agency astronaut Joshua Kutryk spent seven hours and 11 minutes outside the orbiting laboratory, installing and deploying a new roll-out solar array. The spacewalk also marked the 100th U.S. spacewalk from the station.
The rolled-up assembly traveled to the station earlier this month inside the unpressurized trunk of a SpaceX Dragon cargo capsule, according to Space.com. It measured about 10 by 2 by 4 feet while folded and weighed 750 pounds. Menon secured himself at the end of Canadarm2 and carried the array to the station’s port side. Kutryk moved along the station’s backbone truss to the worksite, where the astronauts installed it on the 2A electrical power channel.
The crew mounted the array with bolts and connected its electrical cables to the station’s power system. Space.com reported that the cable work took place during an orbital night pass for safety reasons. Once the array was secured and connected, the astronauts released it for deployment.
No motor was needed to unfold the new panel. Energy stored in its rolled carbon-composite booms extended it to about 63 feet. About 12 minutes after deployment began, the array was fully extended over roughly half of an older, larger solar panel on the P4 truss. Menon and Kutryk finished ahead of schedule and used the remaining time to prepare the final array for its future installation.
The new hardware is part of NASA’s International Space Station Roll-Out Solar Array program, known as IROSA. Unlike a rigid panel that opens in sections, an IROSA launches as a compact cylinder and rolls out after astronauts attach it. NASA says the design reduces mass and volume during launch and uses an autonomous deployment system. NASA tested the approach aboard the station in 2017. Redwire designed, manufactured and tested the flight arrays under a Boeing contract. NASA describes the arrays as about half the size of the legacy wings and says they can produce about 28 kilowatts of additional power. Each new array sits over part of an older wing, supplementing the original equipment rather than replacing it.
The project grew over several years. A technology demonstration tested the roll-out design aboard the station in 2017. The first two IROSAs arrived on a Dragon cargo mission in 2021, and six arrays were installed between 2021 and 2023. NASA requested two more in 2023 after updated power projections. The Oct. 29 spacewalk completed the first of that final pair.
The station’s original solar arrays have exceeded their 15-year design life and show reduced output, NASA and Space.com report. The roll-out panels work alongside the original wings to strengthen the station’s power supply. NASA says the completed eight-array upgrade is expected to increase available power by as much as 30 percent, from about 160 kilowatts to approximately 215 kilowatts. That projection applies to all eight IROSAs together, not to the single panel installed during this spacewalk.
The added power is intended to support research and station operations. It will also help support future work such as the station’s safe, controlled deorbit at the end of its service life. The upgrade shows how astronauts, engineers and cargo teams can extend the usefulness of equipment already in orbit while preparing for the station’s eventual transition.
The Oct. 29 walk was a personal milestone for the crew as well. It was Menon’s fourth spacewalk and Kutryk’s first. NASA counted it as the 285th spacewalk in support of station assembly and maintenance. Kutryk became the fifth Canadian astronaut to conduct a spacewalk, and NASA said the pair were scheduled to return outside on Nov. 5 to install the eighth and final array.
From Earth, the upgrade may look like another panel added to the station’s silhouette. In practice, every installation depends on careful timing, robotic handling, electrical work and coordination among astronauts inside and outside the station and teams on the ground. With one array left, the latest spacewalk brought a multi-year international project close to completion.
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