By Steve Gorman

(Reuters) – A spacewalk that was scheduled for Tuesday in order to fix a faulty antenna at the International Space Station has been postponed indefinitely by NASA. The reason? NASA received a debris notification for its orbiting research laboratory.

NASA officials stated that two U.S. space astronauts were scheduled to depart the station at 7:10 Eastern Time (1210 GMT) in order to commence their work. However, they would be facing a slight increase risk due to debris from an anti-satellite missile testing this month.

NASA announced on Twitter (NYSE 🙂 just five hours before outing was due to begin that the spacewalk would be canceled for now.

NASA received a notification regarding the debris to be placed on board the station. The space agency tweets that teams decided to postpone the Nov. 30 spacewalk due to insufficient information to assess the risks it might pose for the astronauts.

The distance of debris to the station orbiting around 250 miles (402 kilometers) above Earth was unknown. It is also unclear if it had been related to the Russian missile testing.

NASA TV was to live-broadcast the six-and-a half hour “extravehicular activities” (or EVA) operation of astronauts Thomas Marshburn, Kayla Brown. Marshburn (61), a former space surgeon and medical doctor, would make this her fifth spacewalk. Barron, 34, a U.S. Navy sub officer and nuclear engineer, will be making her first spaceflight with NASA.

It is necessary to replace a failing S-band radio communication antenna assembly that has been in use for more than twenty years with an identical spare.

Plans show that Marshburn would have been positioned with Barron at the end a robot arm controlled by Matthias Maurer, a German astronaut, from the European Space Agency. Raja Chari, a NASA crewmate, assisted Raja Chari.

Four astronauts, two Russian cosmonauts, and a NASA astronaut arrived aboard the SpaceX Crew Dragon capsule that launched from Cape Canaveral in Florida on November 11.

NASA reported that Russia conducted an anti-satellite test four days later. This created a dust field in low earth orbit. Seven crew members sought refuge within their spaceships docked to make a quick escape until immediate danger had passed.

According to Dana Weigel (NASA deputy manager for the International Space Station program), the residual debris cloud created by the blasted satellite have dispersed.

NASA estimates that any remaining fragments pose a slight elevated background threat to the entire space station, with a 77% increased risk of spacewalkers getting their suits punctured. This is in comparison to Russia’s missile tests, Weigel stated to reporters Monday.

Weigel explained that NASA still has not fully quantified the extra hazards presented by 1,700 more fragments around its orbit. The 7% increased risk spacewalkers face falls within the range of fluctuations previously observed in “the natural environmental”.

Weigel said that mission managers had canceled smaller tasks in preparation for Tuesday’s spacewalk.

(By Steve Gorman. Gerry Doyle edits