Watch LIVE: Two astronauts repairing Space Station's robotic arm flying at 28,000 kmph

Two Nasa astronauts stepped outside the International Space Station to replace a faulty Canadarm2 wrist joint. The repair is aimed at restoring a vital robotic arm used for cargo operations, maintenance and astronaut support.

In Short

• Chris Williams and Jessica Meir began a planned six-and-a-half-hour ISS spacewalk
• They are replacing a faulty Canadarm2 wrist joint using a spare part
• The malfunction surfaced on May 27 during routine operations aboard station

Two Nasa astronauts are currently outside the International Space Station (ISS), carrying out a critical spacewalk to repair one of the orbiting laboratory's most important robotic systems, while flying at a speed of 28,000 kilometers per hour.

Nasa astronauts Chris Williams and Jessica Meir exited the station's Quest airlock on Tuesday for a planned six-and-a-half-hour extravehicular activity (EVA) to replace a malfunctioning wrist joint on Canadarm2, the ISS's 17.6-metre-long robotic arm.

WATCH NASA SPACEWALK LIVE HERE

The spacewalk, which began at approximately 6:05 p.m. IST, marks the 280th spacewalk dedicated to the assembly, maintenance and upgrades of the International Space Station.

Canadarm2, built by the Canadian Space Agency (CSA), is one of the station's most critical pieces of equipment. The robotic arm is used to capture visiting cargo spacecraft, move astronauts during spacewalks, relocate large modules and support maintenance work outside the station.

The repair became necessary after the arm experienced a malfunction on May 27, when one of its wrist joints drew unusually high motor current and failed to move as expected during routine operations.

Following weeks of analysis, engineers from Nasa and the Canadian Space Agency concluded that the faulty joint needed to be replaced during a spacewalk using a spare component already stored aboard the ISS.

Nasa said such repairs are expected after more than 25 years of continuous operations. Canadarm2 was designed with replaceable parts to allow astronauts to carry out maintenance without returning the hardware to Earth.

During the mission, Williams is serving as spacewalk crew member 1, wearing the spacesuit with red identification stripes, while Meir is spacewalk crew member 2, wearing an unmarked suit.

The EVA is Williams' second career spacewalk and Meir's fifth.

Spacewalks remain among the most challenging tasks astronauts perform. Working in the vacuum of space, astronauts must carefully maneuver while tethered to the station, handling tools and replacement hardware in microgravity as they carry out precision engineering tasks hundreds of kilometres above Earth.

The successful replacement of the wrist joint will restore the robotic arm's full capability, ensuring it can continue supporting spacecraft arrivals, scientific experiments and future maintenance operations aboard the orbiting laboratory.

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