NASA’s astronauts aboard the International Space Station have been told to prepare for an urgent evacuation amid growing safety concerns.
The US space agency and its Russian counterpart, Roscomos, are tracking 50 ‘areas of concern’ related to a growing leak aboard the station.
NASA is now calling the cracks in a Russian service module a ‘top safety risk’ – escalating the threat rating to five out of five.
Astronauts have been warned to stay in the American section when the module is open so they can be close to their spacecraft in case of an emergency evacuation.
Although officials have been aware of the issue since 2019, the exact source of the leak is still unknown.
All potential cracks have been covered with ‘a combination of sealant and patches’ but NASA warned that the leak reached its fastest rate yet in April this year.
Concerns over the station’s safety are now so high that NASA has negotiated with Roscomos to only open the hatch when absolutely necessary and to keep it sealed in the evenings.
And that’s not the only cause for concern, as the space agency has warned that the ISS is at risk of being pelted with micro-meteors and space debris.
American astronauts aboard the ISS have been told to be ready for an emergency evacuation as a leak in the Russian section is branded a ‘top safety risk’
NASA is now tracking 50 ‘areas of concern’ related to a leak in the Russian Zvezda Service Module Transfer Tunnel (labelled) which sprung a leak in 2019
This is not the first time the ISS has sprung a leak. In 2018 astronauts rushed to fix a hole (pictured) which had appeared in the outer wall of the Soyuz capsule on the orbiting laboratory. The origins of the damage remain a mystery
The air leak is located in the Russian Zvezda Service Module Transfer Tunnel which was installed in 2000 and is used to house life support equipment and to access a Russian cargo dock.
In 2019 it was noted that the module had begun to leak a small amount of air through an unidentified crack.
However, despite efforts to seal the module, the amount of air escaping the station has only increased over the last five years.
In February this year, NASA was forced to hold a press conference on the issue as the amount of air escaping temporarily increased from 0.2 lbs per day (0.09 kg) to 2.4 lbs (1.08 kg) per day.
A report published in September by NASA’s Office of the Inspector General (OIG) confirmed that the leak then hit record rates in April – losing 3.7 lbs (1.68 kg) of air every day.
This has prompted the space agency to escalate the threat rating to the highest level and consider plans for evacuation.
In May and June, NASA officials travelled to Russia to discuss ‘heightened concerns’ over the seemingly growing leak.
Speaking to the Washington Post, NASA associate administrator Jim Free says: ‘We have conveyed the seriousness of the leaks multiple times, including when I was in Russia earlier this year.
The Zvezda module is used to access a Russian cargo dock (pictured here). Due to the escalating leak, the Russian space agency has agreed to keep the module sealed except when needed
‘We’ve come to a compromise that they close it in the evening.’
Whenever the hatch is opened for essential use, NASA astronauts have been instructed to wait near their escape vehicles in case of emergency.
In July, NASA paid Elon Musk’s SpaceX $266,000 (£205,000) to prepare a contingency plan to evacuate American astronauts who were scheduled to return to Earth onboard Russian craft.
The agency confirmed that this was due to ‘the ongoing leak detection work’ onboard the station.
Although NASA’s astronauts have been told to be ready for a potential evacuation, it is not believed that the leak poses any immediate threat to human life or the integrity of the station.
The OIG report states: ‘The Service Module Transfer Tunnel leak is not an immediate risk to the structural integrity of the Station, and there are no current concerns of long-term impacts to the overall structure.’
Likewise, ISS program manager Joel Montalbano told a press conference in February that the leak was ‘not an impact right now on the crew safety or vehicle operations, but something for everybody to be aware of.’
NASA and Roscomos are collaborating to monitor the leak and try to identify the source of the issue.
NASA says that the station is safe for the 11 astronauts currently living aboard and the leak poses no immediate threat. However, NASA has told its astronauts to remain in the American side of the station whenever the Zvezda hatch is open in case of the need to quickly evacuate
However, the two agencies are yet to agree on when the leak rate would be considered ‘untenable’.
In the same OIG report, NASA also raised the concern that the space station could be seriously damaged by tiny pieces of material in orbit – escalating the risk rating to the highest level.
The agency wrote: ‘NASA considers the threat of micrometeoroids and orbital debris (MMOD) a top risk to crew safety, the ISS structure, visiting vehicles, and sustained ISS operations.’
NASA has added shields to the American sections which can protect against pieces of debris up to 3cm but warns that it does not have plans to add protection from larger pieces.
However, there are now an estimated 100 million pieces of small debris which are not being tracked and could still damage or destroy spacecraft.
In the report, NASA notes that the growing risk posed by orbital debris also poses a serious issue for any plans to safely evacuate the ISS crew in an emergency.
They write: ‘Due to the high costs and a limited budget, the lack of ready-to-launch vehicles prevent the Agency from having an immediate response capability if crew vehicles encounter significant damage and are no longer safe for crew evacuation.’
The issue is that the ISS is already a decade older than its planned operational lifespan and is beginning to seriously show its age.
NASA also noted that tiny meteorites and space debris were another top-level risk which could damage spacecraft before the crew have a chance to evacuate. Pictured: the ISS seen from a satellite in June 2024
In September, NASA estimated that there were 588 replacement parts aboard the station that were operating beyond their intended lifetime.
NASA has planned to use the station up until 2030, at which time it will be burned up in a controlled de-orbit.
SpaceX has been contracted to build a vehicle which can safely push the ISS back down to Earth for a cost of up to $843 million (£650 million).
However, as Russia refuses to commit to extending the station’s lifespan until 2030, NASA has admitted that the ability to perform a controlled deorbit is now ‘unclear’