After receiving a warning that debris might pass close to the International Space Station, NASA rescheduled a spacewalk by two astronauts outside the station just several hours before it began. NASA stated in a statement released early November 30 that a “debris notification” received on November 29 evening prompted the agency to postpone astronauts Kayla Barron and Tom Marshburn’s spacewalk, which was set to begin at approximately 7:10 a.m. Eastern. They were going to substitute an S-band antenna on the station’s truss that had just stopped transmitting data.
“Teams have opted to postpone the spacewalk until further information is available due to a lack of opportunity to adequately analyze the danger it potentially represents to the astronauts,” NASA stated in a statement. The debris in question, as well as the timings and distances of the closest point to the station, were not identified by the agency.
The announcement came just hours after NASA station management downplayed the threat posed by debris which was created by a Russian anti-satellite missile test on November 15 during a news conference about the spacewalk. Thousands of bits of debris were formed during the test, prompting ISS crews to seek shelter in their Soyuz as well as Crew Dragon vehicles for numerous hours thereafter. “We had a heightened, increased worry for roughly 24 hours following the occurrence when ISS moved through the debris’ orbit,” Dana Weigel, who serves as the deputy program manager of NASA ISS, said at the November 29 briefing. “The debris has dispersed quite a deal more since then.”
She claims that the station’s background debris environment is now double what it was before the test. However, every minute of debris, especially micrometeoroids, poses the greatest threat to the spacesuits. According to her, the ASAT test centered on modeling raised the danger to the suits by just approximately 7%. “Falls within the range of what we’ve had for the EVAs over the previous few years,” says the astronauts’ risk.
Weigel later clarified that the precise threats to the suits apply to debris infiltrating the suit, not necessarily a “catastrophic” entry. Within the course of a conventional EVA of 6.5 hours, the risk of such an incident is 1 in 2,700.
The spacewalk was modified by station managers, who reduced the amount of “get-ahead” tasks available to the astronauts if they finished the antenna tasks ahead of time. Routing an Ethernet wire and releasing bolts for the spare nitrogen tank was among the duties deleted from the spacewalk, which NASA said may be pushed to future spacewalks.”We didn’t comprehend what the debris environment danger increase was since we had to make the decision related to the content of EVA a few weeks ago and we didn’t have all assessment data in,” Weigel explained. “When it came to removing items from the spacewalk, we were cautious.”