Editor's note: A previous version of this article stated the debris was caused by the destruction of a Russian satellite. That has not been confirmed by NASA.

NASA called off the International Space Station's first spacewalk for SpaceX's Crew-3 members due to a debris notification.

What You Need To Know

  • Spacewalk is postponed and will resume once NASA gives the all clear

  • The existing S-band antenna was flown to the Space Station 20 years ago

  • The operation will the first spacewalk for Expedition 66

The spacewalk had been scheduled for Tuesday at 7:10 a.m. EST, but NASA issued an advisory that stated on Monday evening, the space agency decided to delay the spacewalk. The spacewalk has now been rescheduled for Thursday, NASA indicated on Twitter.

"... NASA received a debris notification for the International Space Station. Due to the lack of opportunity to properly assess the risk it could pose to the astronauts, teams have decided to delay the spacewalk until more information is available," NASA stated in a press release.

While NASA has not confirmed the origins of the debris, the issue has been in the news in the last few weeks. Russia destroyed one of its satellites during an anti-satellite (ASAT) weapon test on Monday, Nov. 15, causing debris. The test caused an international backlash, with the U.S. condemning the move. 

“Today, miles above us, there are American astronauts and Russian cosmonauts on the International Space Station,” State Department spokesman Ned Price said on Nov. 15. “What the Russians did today with these 1,500 pieces of trackable, orbital debris, poses a risk, not only to those astronauts, not only to those cosmonauts, but also to satellites to the interests of all nations.”

During a press conference on Monday, Nov. 29, Dana Weigel, the NASA deputy manager of the ISS, said while the agency continues to track the fallout from the Russian anti-satellite test that created a large debris field in mid-November, the current risk during this spacewalk falls within a safe range of operation.

“We run different models and predictions to understand what our environment is — of course, most of these pieces that we're talking about with the suit are much smaller than what we could track,” Weigel said. “So that's done through just modeling and understanding of the environment from experiments and from previous knowledge. So, this particular EVA it's MMOD (meteoroid and orbital debris) risk falls within the family of what we've had for EVAs over the last few years.”

She noted that there’s a roughly 7% increased risk of penetration to either the spacesuits or the space station, which Weigel stressed “doesn’t mean it’s a catastrophic event.” 

“For the suit itself, there's a certain size of penetration that is supportable. There's an emergency oxygen package on the suit that would feed it for a while. So, it covers that range, and of course, larger items,” Weigel said. “Also, just to give you a feel for it, when we talk about EVA risk, it's generally around one in 2,700. So that's considered the risk of having some size of a penetration over the course over the duration of a six-and-a-half-hour EVA.”

Multiple countries previously condemned the destruction of the defunct Soviet satellite, which threatened the space station along with many other satellites. NASA Administrator Bill Nelson said in an interview with Spectrum News that the Russian military acted without input from Roscosmos, the Russian space agency.

“And that’s what’s so unbelievable," Nelson said. "I think it demonstrates that it was one hand of the Russian government not knowing what the other hand was doing. I would suspect they won’t be doing that again.”

In the meantime, the spacewalk is postpone and will resume once NASA gives the all clear.

The reason for the spacewalk

Two Crew-3 astronauts will get to check off their first spacewalk as part of Expedition 66 aboard the International Space Station when it does happen. 

The 6.5 hour EVA (extravehicular activity) will be done to replace a communication antenna that has been active on board the ISS for the past 20 years.

NASA tapped astronauts Tom Mashburn and Kayla Barron to perform the operation. They will be replacing a degraded S-band Antenna Subassembly (SASA) with a spare that was flown to the Space Station about a decade ago.

While the antenna’s degradation “has had limited impact on station operations, mission managers decided to install a new antenna to ensure communications redundancy," NASA said in a statement. "The space station has additional low-rate S-band systems, as well as the high-rate KU-band communications system that relays video."

Marshburn, who will be conducting his fifth spacewalk, will be attached to the end of the Canadarm2 robotic arm to work with Barron. 

European Space Agency (ESA) astronaut Matthias Maurer will be operating the arm from inside the station, and NASA astronaut Raja Chari be watching over his shoulder as well as doing some communications between the crew outside the Space Station as well as with the EV team on the ground. 

“We found out we had a degraded S-band assembly in mid-September. That timing allowed us to have Tom and Kayla go into our neutral buoyancy laboratory or big pool where we practice spacewalks and practice our exact spacewalk that will be executed tomorrow,” said Vincent LaCourt, NASA’s spacewalk flight director. “So that's a great advantage to give them that practice for success tomorrow.”

Ahead of last week’s launch of the new Russian node module, Prichal, Nelson said he spoke with Dmitry Rogozin several times and reassured the good working relationship in space with Russia. Nelson added that he was invited to travel to Moscow for an in-person meeting.

“COVID allowing, I will go at the first opportunity,” he said. “We have a great partnership with the Russian space agency and have ever since the Soviet Union, since 1975 when Tom Stafford and Alexi Leonov, the two respective commanders, docked together and lived in space for nine days. And we have cooperated with the Russians ever since.”

Weigel said on Monday that they are still working to iron out an arrangement with Roscosmos for a crew swap and to fly a cosmonaut on a Crew Dragon capsule as early as next fall on the Crew-5 mission.

“We've had a lot of good discussions with our Russian colleagues about doing a crew exchange,” Weigel said. “I think, as you know, it's always been our goal to fly astronauts and cosmonauts on both vehicles, both the Soyuz and our crewed vehicles. And so those discussions are moving along very well.”

The 254th spacewalk for the ISS will resume at a later date with NASA offering live coverage.