The International Space Station has a pesky leak – not even NASA has a concrete plan for it

It won’t be easy to survive the aging International Space Station for another six years.

A recent report from NASA’s Office of Inspector General last month highlighted some of the major challenges of ensuring the safe flight of the ISS, from replacing aging parts and maintaining supply lines 250 miles above the planet Space debris and a worryingly persistent leak in the Russian space segment of the station.

But despite its advanced age, the venerable ISS still plays an important role. For one thing, it’s still a cornerstone of NASA’s plans for the Moon and Mars, and it still plays a crucial role in research from earth sciences and medicine to astronomy and physics. This puts NASA and other space agencies that maintain the ISS in a difficult situation: How can they keep this deteriorating vehicle alive? At the moment, no one is quite sure.

Logistics, location and leaks

An aging space station has some of the same problems as an aging car – just with greater risk. Parts wear out more frequently, but the older the vehicle gets, the harder (and more expensive) it is to find replacements. Now imagine if your aging car was 250 miles above the Earth’s surface and only a handful of vehicles in the world could actually get there to deliver parts.

“Upgrades to critical replaceable parts may become more difficult to obtain as suppliers reduce or cease production,” the OIG report said. “This risk is increased by the current reliance on a single launch provider [SpaceX] for cargo and crew.” Boeing’s Starliner spacecraft, whose crew is still stuck on board the ISS after a test flight fiasco in June, was supposed to help solve exactly this problem.

But the elephant in the room is a leak in the Russian part of the channel.

Why is the ISS leaking?

About 1.2 pounds of air escapes every day through cracks in the service module transfer tunnel that connects Russia’s Zvezda module to a docking port for unmanned Russian Progress cargo ships. At its worst, in April 2024, the tunnel was leaking 3.7 pounds of air per day, but repair work earlier this year helped reduce the loss.

To put the leak into perspective, the ISS has about the same volume of pressurized, air-filled space as a Boeing 747. Astronauts don’t have to deal with the space equivalent of an airplane’s door plug falling off mid-flight, but if their Life Depends on It When it comes to keeping the air in and the vacuum of space out, any leak is cause for concern.

“No impact to crew safety or vehicle operations at this time, but something everyone should be aware of,” NASA ISS program manager Joel Montalbano said in a February 2024 statement, when the leak was 2.4 pounds per day was.

The severity of the leak has fluctuated since it was discovered in September 2019, as some small cracks have been repaired and others opened. Overall, it’s a worsening problem that the OIG report calls a “top security risk.”

Repairs — primarily applying sealant to cracks as soon as they are found — have kept the leak at a “manageable” level over the past five years, but cosmonauts are also trying to keep the Zvezda module’s hatch closed as much as possible to limit air loss from the rest of the station.

“Zvezda’s hatch remains closed as much as possible, including near the Progress spacecraft’s cargo operations,” a NASA spokesman said Inverse.

High stakes in low Earth orbit

If the leak becomes “uncontainable,” as the OIG report puts it, the transfer tunnel may have to be closed entirely, like the sealed off wing of a slowly decaying mansion in a gothic horror novel – albeit in space.

This could be a bigger problem for the ISS than it seems at first glance.

The transfer tunnel contains one of the Russian module’s four docking ports for cargo ships, so a loss could cause traffic problems and delays in supplying the station. And cargo ships docked at this port often fire their own engines to bring the ISS back into its proper orbit; At an altitude of 250 miles above Earth’s surface, there are just enough air molecules floating around to gradually slow the station and drag it downward unless it receives a periodic boost. Without the occasional nudge from a visiting Progress ship, the ISS would have to use its own engines for this task. This would require burning more fuel and putting more strain on aging systems.

Meanwhile, NASA and Roscosmos don’t even agree on what counts as an “unsustainable” leak rate. And the actual cause of the leak remains unclear; Cosmonauts have found and sealed several cracks over the years, but leaks continue to occur.

“Cosmonauts aboard the space station conducted inspections of the module’s interior surfaces using an instrument that can detect even the smallest surface defects,” a NASA spokesman said. “Several areas of interest have been identified that are subject to future inspections by Roscosmos. Roscosmos has not confirmed that these areas of interest are rifts. These can be harmless imperfections that are normally seen on a surface, such as a small scratch.” According to the OIG report, the main suspect at this time is a series of welds both inside and outside the tunnel.

The “international” part is key

The relationship between NASA and Roscosmos has been strained in recent years. Russia has not yet committed to keeping its part of the ISS running until 2030. This includes cost sharing, maintenance, inspection of its modules and certification that they are structurally sound. Nor has it joined NASA’s plan to deorbit the ISS by launching it into Earth’s atmosphere using a spacecraft. This plan requires the use of Russian engines to keep the space station at cruising altitude and in the correct orientation until it is time to crash it.

“Without Russia’s commitment to the current deorbit plan, the ability to conduct controlled deorbit is uncertain,” the OIG report said. “NASA expected that Roscosmos would commit to the agency’s ISS deorbit plan in the summer of 2023 – which requires a continued partnership through 2030. However, as of June 2024, negotiations continue and no agreement has yet been reached.”

But just like the transfer tunnel, the relationship between the two space agencies has not yet become entirely untenable.

“NASA is working with Roscosmos,” the NASA spokesman said in response to questions about the leak. “Station partners exchange information about the status of the leak, onboard investigations and remedial actions.”

Are we really ready to lose the ISS?

If all goes according to plan, the International Space Station will go out in a blaze of glory sometime in 2030 or 2031. NASA announced in July that it had awarded SpaceX a contract to design and build a spacecraft to launch the station into Earth’s atmosphere – allowing NASA to control when and where the 450-ton station (if one it weighs on Earth) enters the atmosphere and where most of the debris from its decay will end up (in a remote area of ​​the Earth). Pacific Ocean, known as Point Nemo or Spacecraft Cemetery).

But that’s not guaranteed.

Before the ISS comes to a close in 2030, NASA hopes to replace it with commercially operated space stations that would host a mix of space agency researchers and private visitors (think, most likely, a combination of space tourism and corporate research and development before).

“NASA’s goal is to be one of many customers in a robust commercial market in low Earth orbit, where on-orbit destinations and cargo and crew transportation are available as services to the agency,” the NASA spokesman said. “Shifting operations and services in low Earth orbit to the private sector will give NASA more time to focus on human space missions to the Moon as part of the Artemis campaign and ultimately to Mars.”

However, these longed-for commercial stations do not yet exist, and in its latest report, NASA’s OIG is skeptical that they will make it into orbit in time to replace the ISS. If not, we face a difficult decision: either give up a place in LEO – which would mean giving up much of the research that will give humans a foothold on the Moon in the long term, not to mention the development of new drugs for it Use here on Earth – or find a way to keep the aging station running a little longer.