"Possibility of catastrophic failure": Inside the space station leak problem that has NASA worried

() – A segment of the International Space Station (ISS) controlled by Russia has a leak that allows pressure and air to escape. The situation is at a critical point as cosmonauts scramble to repair problem areas and officials at the Russian space agency, Roscosmos, and NASA disagree about the seriousness of the problem.

The football-field-sized space lab must remain pressurized and filled with breathable gases to house a rotating crew of astronauts, which it has done since 2000 in separate but connected sections of Russia and the United States. The problematic leaks were first identified in 2019 in a tunnel connecting a Russian module, called Zvezda, to a docking port that welcomes spacecraft carrying cargo and supplies.

But the rate at which the module loses air reached a new high this year.

According to a report recent report from NASA’s Office of Inspector General, oversight officials in the United States now consider this issue to be the most pressing problem facing the aging space station and one that could jeopardize the safety of the crew.

The US space agency “has expressed concern about the structural integrity of the (leaking module) and the possibility of catastrophic failure,” said former NASA astronaut Bob Cabana, chairman of the agency’s ISS advisory committee, during a meeting on the subject held on Wednesday.

But although Roscosmos has ordered its cosmonauts to find and fix problems, which has reduced the rate of leaks, the Russian team “does not believe that catastrophic disintegration… is realistic,” Cabana said.

“The Russians believe it is safe to continue operations but they cannot prove it to our satisfaction,” Cabana added. “And the United States believes it is not safe, but we cannot prove it to Russian satisfaction.”

Disagreements persist despite a September meeting that Cabana says took place in Russia.

Now, the United States is pushing for independent experts from both sides to evaluate the issue and help the two space agencies reach a consensus on the cause and severity of the leaks.

The United States has already taken steps to create its own team of experts, Cabana said. Russia has not yet complied with the recommendation. Still, Cabana said the September meeting with Russia was “extremely successful.”

Roscosmos did not respond to an email request for comment.

Meanwhile, astronauts and cosmonauts – the Russian term for astronaut – aboard the space station have been required to take precautionary measures, such as keeping the leaking segment sealed at all times, except when it must be opened to unpack cargo from the spaceships arriving at the nearby port.

When astronauts open that segment, they close the hatch that separates the American and Russian parts of the station, NASA astronaut Michael Barratt explained during a Nov. 8 press conference.

“We have taken a very conservative approach,” Barratt said. “It’s not a comfortable thing, but it’s the best agreement between all the smart people on both sides – and it’s something we live with as a crew.”

As the orbital laboratory ages, both agencies are currently faced with making crucial decisions about how and when to cease operations and safely dispose of the station. The current leak issue raises serious questions about the safety of the station and the ability of NASA and Roscosmos to reach a consensus.

NASA and Roscosmos have known for years that the Russian module suffered gradual leaks.

The problem is compounded by the fact that the suspected cracks are “very small, not visible to the naked eye, and have supports and pipes nearby, making it difficult to introduce diagnostic tools into these areas,” NASA said in a statement. statement to on Thursday.

Efforts to mitigate the leaks have avoided the problem for now. However, the leak rate still “ranges between 2 and 2.5 pounds (of air) per day above the space station baseline,” according to NASA. To put it in context, the space station aims to remain pressurized at 14.7 pounds per square inch absolute, which mimics the pressure of the atmosphere at sea level here on our home planet.

The space agency did not respond to a request to compare the current rate of leaks with the peak recorded earlier this year.
The US and Russian technical teams do not agree on the exact cause of the problem, according to Cabana.

Russian experts believe that vibrations – which could be caused by mechanical systems such as those used for energy storage – on the space station are stressing the walls, causing “high cycle fatigue,” or a phenomenon in which a relatively Soft starts to crack and wear down a metal to the point of failure over long periods of time.

NASA, for its part, believes that the picture is more complicated and that several factors are involved, such as mechanical stress, environmental exposure and “residual stress” or possible problems derived from the manufacturing of the materials used in the module. of transfer, according to Cabana.

A report released in September by NASA’s Office of Inspector General also notes that while NASA and Roscosmos agree that it may be necessary to permanently close the problematic segment if the leak rate reaches an “unsustainable” level, the two Parties have not reached an agreement on how exactly to define “unsustainable.”

However, although space agencies continue to disagree on the severity of the problem, Cabana and Barratt and NASA’s ISS program manager, Dana Weigel, in a statement said that NASA and Roscosmos are in close communication on the issue.

“We have a very open and transparent relationship with Russian cosmonauts,” said Barratt, who returned from a 232-day stay on the International Space Station in late October. “It is a very integrated crew.”

While NASA and Roscosmos work to fix the leaks, the US space agency has taken some steps of its own to ensure the safety of astronauts.

In addition to requiring astronauts to close the entrance to the Russian section when the Zvezda transfer tunnel is open, the US agency is now placing an additional “seat” aboard SpaceX’s Crew Dragon spacecraft.

The extra seat sits on top of an area of ​​the spacecraft typically used for cargo storage, and is essentially a piece of foam that an astronaut can strap into if they need to get home in the Crew Dragon capsule in an emergency.

The additional seats are reserved for NASA astronauts traveling to the space station on Russian Soyuz spacecraft, as they have done for years under a seat-swapping agreement between the US and Russia.

NASA astronaut Don Pettit, for example, is currently at the space station after arriving aboard the Soyuz MS-26 spacecraft on September 11. However, if the space station is deemed unsafe and Pettit cannot access the spacecraft docked with the Russian module, NASA said he has the option of returning home via the visiting SpaceX Crew-9 vehicle in an extra seat next to the space station. four astronauts assigned to that vehicle: Sunita Williams, Butch Wilmore and Nick Hague of NASA and Roscosmos cosmonaut Aleksandr Gorbunov.

NASA has contingency plans for crew safety, but the space agency is also grappling with the fact that the leak of the Russian module may pose a threat to the safety and longevity of the space station.

In its report, the Office of the Inspector General notes: “Although it is possible for the ISS to operate if the hatch (to the affected area) is permanently closed, it could affect cargo delivery because there would be one less cargo delivery port,” the report states. “Closing the hatch permanently would also require additional propellant to maintain the altitude and attitude (or orientation) of the Station.”

The space station routinely requires spacecraft docked to it to propel the outpost into orbit to maintain its trajectory, preventing Earth’s gravity from pulling it back down. Typically, such thrusts are carried out by docked Russian spacecraft. But NASA has already been testing the use of American spacecraft for that task.

The leak problem erupts at a critical time for the orbital laboratory, which NASA hopes to continue operating with its five partner agencies at least until 2030. In addition to Roscosmos, they include the Canadian Space Agency, the European Space Agency and the Japan Aerospace Exploration Agency. Russian officials, however, have not committed to the space station beyond 2028 and are unlikely to give firm answers about Roscosmos involvement after that deadline until at least 2025, according to the OIG report.

NASA’s goal is to continue conducting essential research at the orbital laboratory until an alternative space station comes online. The US space agency intends to hand over to the private sector the task of creating and exploiting this new space laboratory, and a series of commercial groups are currently designing and developing their own platforms. Among those companies are Blue Origin, funded by Jeff Bezos, and Vast, a SpaceX partner.

The space agency aims to launch lucrative contracts to carry out the work in 2026.

Still, it’s unclear whether the commercial destinations will be ready before the space station is forced to retire.
“The station is not young,” Barratt said. “You would expect there to be more wear and tear elsewhere.”