Two NASA astronauts conducted a spacewalk outside the International Space Station (ISS) to replace a broken joint on the station’s robotic arm. The mission, carried out on a Tuesday, proved to be successful.
During the seven-hour, 20-minute excursion, the astronauts replaced a faulty 200-pound “wrist” joint on the robotic arm. Canadian astronaut Jenni Gibbons praised their effort, saying, “That is a good install, you guys. I know that was tough. Wonderful work.”
The robotic arm, known as Canadarm2, encountered issues on May 27 when flight controllers in Houston noticed it was drawing more current than usual. The Canadian Space Agency supplied the arm, and their experts joined NASA managers to determine that the joint needed replacement. The station is equipped with spare parts like these to facilitate maintenance.
Astronauts Jessica Meir and Chris Williams initiated the spacewalk at 8:20 a.m. ET by switching their spacesuits to battery power. This marked the third spacewalk of the year and the 280th conducted at the ISS. Meir, on her fifth spacewalk, and Williams, on his second, prepared for the operation by setting up foot restraints and positioning the spare joint.
The process involved detaching the arm’s “hand” or latching end effector, along with two healthy joints, to make way for the replacement. The faulty joint was moved to temporary storage during the operation.
Flight director Fiona Antkowiak outlined the mission plan: “We’ll remove the failed joint five, replace it with the spare joint and then once that’s back on the arm, our last major task will be to get that LEE cluster that we temporarily stowed and put it back onto the robotic arm so that we have a fully assembled arm at the end of the spacewalk.”
Within four and a half hours, the astronauts successfully installed the new joint. They completed the reattachment of the LEE cluster as planned five and a half hours into the spacewalk. The arm was powered up soon after, confirming good electrical connections through the new joint.
Nasa commentator Sandra Jones confirmed the success, stating, “Today we did hear good confirmation that … Canadarm2 has two good strings of power and data to the arm.”
Williams and Meir secured their tools and returned to the airlock, bringing the failed joint back for eventual repairs on Earth. The arm plays a crucial role in ISS operations, used in tasks like capturing Cygnus cargo ships and aiding in maintenance.
Nasa plans to retire the ISS by 2030, but will maintain the arm until then, as Bill Spetch emphasized: “Overall, the arm is critical for station operations and continued maintenance of it throughout to the end of life.”