NASA Astronauts Perform Live Spacewalk to Repair ISS Robotic Arm at 28,000 kmph
In a breathtaking demonstration of precision engineering and human grit, two NASA astronauts stepped outside the International Space Station (ISS) to execute a complex, live-streamed repair mission. Operating in the harsh vacuum of space while hurtling around Earth at a staggering velocity of 28,000 kilometers per hour, the spacewalkers successfully replaced a critical structural component on the station’s iconic robotic arm.
The mission, designated as US Spacewalk 95, was broadcast live to millions of viewers worldwide via major digital and streaming platforms. For nearly seven hours, the astronauts worked meticulously in extreme microgravity, proving once again that despite the station’s aging infrastructure, human adaptability remains humanity's greatest asset in the cosmos.
The Crisis in Orbit: What Went Wrong with Canadarm2?
The urgency behind the orbital operation began unfolding on May 27, when one of the main mechanical joints on the Canadarm2 robotic arm malfunctioned during routine station maneuvers. Telemetry data analyzed jointly by engineers at NASA and the Canadian Space Agency (CSA) revealed that a critical wrist joint was drawing an unusually elevated motor current and refusing to move as commanded.
Canadarm2 is a 17.6-meter-long, Canadian-built robotic powerhouse that has been indispensable to the day-to-day operations of the ISS for over 25 years. It acts as the primary tool for capturing arriving commercial cargo spacecraft, moving multi-ton station modules, and safely transporting astronauts during delicate extravehicular activities (EVAs).
Because the software-based overrides could not fix the internal mechanical failure, space agency officials determined that a physical swap was required. Fortunately, the robotic arm was explicitly designed with modular, orbit-replaceable parts, and a 200-pound (90-kilogram) spare replacement joint was already securely tucked away in the station's external storage inventory.
Stepping into the Vacuum: The Spacewalkers
The challenging task of replacing the heavy wrist joint fell to veteran NASA flight engineers Chris Williams and Jessica Meir. Both astronauts are highly experienced, having completed a successful seven-hour spacewalk together earlier in the year to install solar array modification kits.
The countdown to the repair began inside the Quest airlock, where the duo donned their heavily pressurized Extravehicular Mobility Units (EMUs)—essentially personalized, self-contained spacecraft designed to protect them against wild temperature swings ranging from -157 to 121 degrees Celsius. To aid ground controllers and viewers tracking the live broadcast, Williams served as Spacewalk Crew Member 1, wearing a suit distinguished by bright red identification stripes, while Meir wore an unmarked white suit as Crew Member 2.
At approximately 6:05 PM IST, the airlock depressurized, and the outer hatch swung open. Tethered securely to the orbital complex, the astronauts stepped out into open space, officially initiating the 280th spacewalk in the history of ISS assembly and maintenance.
Seven Hours on the Edge: The Precision Repair
Performing intricate mechanical labor while moving at 28,000 kilometers per hour introduces an extraordinary set of physics challenges. While the astronauts do not feel the speed because they are moving at the exact same velocity as the space station, they must constantly battle inertia, the lack of leverage in microgravity, and the bulkiness of their multi-layered space gloves.
Assisting from inside the comfort of the station’s laboratory cupola, European Space Agency (ESA) astronaut Sophie Adenot and NASA's Jack Hathaway worked as the essential "inside crew". They meticulously piloted the uninjured segments of Canadarm2 via internal control sticks, positioning the faulty joint directly into the path of the waiting spacewalkers outside.
Using specialized, battery-powered pistol-grip tools engineered specifically for microgravity use, Meir and Williams began unbolting the malfunctioning 200-pound wrist joint. Every movement required careful counter-anchoring; without holding onto a foot restraint or handle, twisting a bolt would simply spin the astronaut's body in the opposite direction.
Once the broken joint was detached, the duo carefully maneuvered it across the truss structure to an external storage platform and unboxed the fresh spare joint. After aligning the delicate data and electrical connectors, they bolted the new component into place. Back on Earth, teams at Mission Control in Houston and the CSA watched in relief as initial diagnostic tests confirmed that the new joint was receiving clean power, drawing normal electrical currents, and responding perfectly to baseline movement commands.
The Human Factor and the Future of the ISS
Beyond the impressive technological triumph, the successful execution of US Spacewalk 95 highlights the irreplaceable value of human presence in low Earth orbit. While automated algorithms and remote ground commands handle the vast majority of the station's daily scientific and environmental functions, unexpected mechanical failures require the unique problem-solving abilities, fine motor skills, and spatial awareness of human beings.
As the International Space Station continues to push deep into its third decade of continuous human habitation, maintenance missions like this are becoming increasingly standard. Components that were installed over twenty years ago are naturally reaching the end of their operational lifespans. By designing systems with interchangeable parts and training crews to perform complex external surgery, international space agencies ensure that the orbiting outpost remains a safe, completely functional home for cutting-edge scientific research before its planned retirement down the road.
With the repair officially complete, Williams and Meir gathered their tools, inspected each other’s suits for any signs of wear or micrometeoroid damage, and re-entered the Quest airlock, successfully wrapping up another historic day of work on humanity's frontier.
Major Trusted Sources for This Report
The timeline, engineering metrics, technical details, and personnel assignments presented in this news breakdown are compiled based on operational updates and official briefings released by the following organizations:
India Today Science Desk
National Aeronautics and Space Administration (NASA Headquarters)
Canadian Space Agency (CSA Media Relations)
Hindustan Times World News
Fox 35 Orlando Space Bureau
Space.com Editorial Network