NASA has spent the last few weeks getting ready for two spacewalks at the International Space Station (ISS), its first in eight months. But just hours before NASA astronauts Mike Fincke and Zena Cardman were due to begin the first of the two walks on Thursday,

NASA has postponed an International Space Station (ISS) spacewalk that was scheduled for Thursday. "The agency is monitoring a medical concern with a crew member that arose Wednesday afternoon aboard the orbital complex," the agency wrote. On Thursday, NASA added that ending Crew-11's mission early was on the table.

NASA astronauts Mike Fincke and Zena Cardman to conduct Expedition 74's first 2026 spacewalk, installing hardware and searching for microorganisms on ISS.

During a spacewalk outside the International Space Station, Russian cosmonaut Sergey Prokopyev jettisoned a 5-kilogram bundle of obsolete hardware into the vacuum of space. Credit: NASA | mash mix by Space.

A Crew-11 member, who NASA has yet to identify, had an undisclosed medical concern that triggered the agency to accelerate their return to Earth.