ISS Spacewalk Postponed Over Debris Threat: NASA

A spacewalk scheduled for Tuesday has been postponed due to a space debris warning.

Originally, the plan was for two of the astronauts -- Dr. Thomas Marshburn and Kayla Barron -- who recently arrived at the International Space Station (ISS), to go on a spacewalk to replace a "faulty antenna system" Tuesday. Apparently, the antenna recently lost the ability to send signals back to Earth, so the mission managers decided to install a new one.

For the spacewalk, Marshburn and Barron were set to exit the Quest airlock at about 7.10 a.m. EST to begin the spacewalk that was expected to last for about six hours and 30 minutes.

However, NASA announced the postponement in a short update, explaining that it received a "debris notification" for the ISS on Monday evening but did not have enough time to assess the threat.

"Due to the lack of opportunity to properly assess the risk it could pose to the astronauts, teams have decided to delay the Nov. 30 spacewalk until more information is available," NASA noted, adding that ISS operations and schedules can "easily accommodate" the delay.

The agency did not specify the debris responsible for the delay, but the postponement came just hours after NASA station managers "downplayed" the risk posed by the debris field generated by the Russian anti-satellite weapon (ASAT) test earlier in the month, reported SpaceNews.

"As ISS passed through the orbit of the debris, we had a heightened, elevated concern for about 24 hours after the event," Dana Weigel, deputy manager of the ISS program at NASA, said during a news briefing Monday as per SpaceNews. "Since that time the debris has dispersed out quite a bit more."

During the space debris "event" on Nov. 15, astronauts aboard the ISS had to prepare for a possible evacuation, taking shelter in the Soyuz and Crew Dragon vehicles for a few hours after the test. The U.S. slammed Russia over the said event, calling it a "dangerous and irresponsible" behavior that "jeopardizes the long term sustainability of outer space."

Had the spacewalk not been postponed, it would have been Marshburn's fifth spacewalk and Barron's first one. It also would have marked the 245th spacewalk for the "assembly, maintenance and upgrade" of the ISS, which celebrated its 21st year of continuous human presence this year.