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Leak on ISS traced to “fracture”

Not good news: According the Russian news source TASS, Russian astronauts have pinpointed the location of the slow leak on ISS to ” a fracture in the intersection compartment of the Russian Zvezda module.”

The astronaut also called it a “scratch,” which means the fracture is not yet confirmed. They will do more testing to find out if this is the leak source in the coming days.

If it is a fracture, the ramifications could be very serious. It appears the “intersection compartment” is the area where the aft docking port is located, which is also the area where many Progress freighters have docked in the twenty years since Zvezda was launched. Thus, this could be a stress fracture that can only get bigger with time. Its location might also preclude further dockings at this port, limiting arrivals of future Progress cargo ships.

Fun fact: They pinpointed this location using a floating tea bag.

The tea bag’s sway in zero gravity conditions towards the air leak overboard the space station was registered by cameras, the cosmonaut said. “We believe that we have really identified the probable leakage area. We have distributed a tea bag [in the Zvezda module] before closing the transfer chamber,” Ivanishin said.

The tea bag’s movement was recorded, the Russian cosmonaut said.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

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  • Jay

    So looking at the history of dockings to the aft port of Zvesda, there were 35 Progress dockings, with the rest going to the nadir port or the PIRS port, plus 5 ESA ATV dockings, but I cannot find out how many Soyuz dockings to the aft port of Zvesda. I am willing to bet a Coke that it has been more than 50 dockings altogether.

    If the aft port is worn out, will they make an aft port extender- a new aft port connected to the old aft port or just close it off?

    Once PIRS is pulled and replaced with your favorite module, Nauka, they are just replacing the nadir docking port there. I do not see many docking to the zenith port of Zvesda, they might now move more traffic there.


  • Rodney

    It could be both. Sometime, 20 some years ago, someone, accidentally, put a little blemish on the structure. This is the “scratch.” Now, after 20 years of thermal and pressure cycling, the slight blemish has propagated through the thickness. And the crack will continue to grow. Usually, in conventional structure, we would just rivet a doubler over the bad area. That would be difficult in space with a pressurized structure. In this case, I would seal up the offending area and then glue a patch over the sealed crack. Some kind of really stiff, in shear, adhesive and a metal plate to make sure the load goes around the repaired crack.

  • Has Russian / Soviet space engineering been worse than that of the IS or other countries? If you take away the Soviet attempts to reach Mars, the probability of failure goes down significantly. Mir has its issues. There was the hole made by an “unsteady hand” in the Russian section of the ISS and now this.

  • Captain Emeritus

    Cast-off Zvezda, along with the two identical docking modules Pirs and Poisk and the cargo docking module Rassvet.
    Rename it all, MIR-3.
    Good riddance.

  • sippin_bourbon

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  • Markus

    So, although Zvezda has been in orbit for 20 years now, the actual age of the structure is more like 35 given the unit was originally constructed in the mid 80s. I’m not saying that is a contributor to the problem, but most equipment has a useful life and surely 15 years of Soviet and post-Soviet storage can’t have contributed to the unit’s on-orbit longevity. I realize it was fit for purpose when launched, but that doesn’t mean the unit was ever built with the expectation that it would be in use 35 years later..

  • “We have distributed a tea bag [in the Zvezda module] before closing the transfer chamber,”

    So Russian. Cultural, simple, effective.

  • pzatchok

    Was not this the module Russia was threatening to disconnect and use as their own space station in the future?

    Its a giant can.

    Someone build one inside the next year and launch it on a Falcon Heavy.
    Dock it and transfer everything from Zvezda to the new module.

  • Lee Stevenson

    I litteraly laughed out loud regarding the Russians using a teabag to identify the source of the leak! @Blair Ivey…. You nailed it! NASA or the ESA would have spent millions on a study group, then many more millions developing a dedicated leak detector.
    Although the scenario is worrying, I guess that given the age, and the wear and tear on the ISS, it is not surprising that bits are showing their age. This is actually going to give good data which (as long as it is shared!) will be useful for any future missions to mars and beyond.
    There is just one question, which as an Englishman, will keep me up at night for days to come….. How the bloody hell does one make a decent pot of tea in zero G???

  • James Street

    “There is just one question, which as an Englishman, will keep me up at night for days to come….. How the bloody hell does one make a decent pot of tea in zero G???”

    Ha! I’m glad I’m not the only one perplexed by that sentence. As I was puttering around doing my Saturday chores yesterday I spent all day trying to design in my head a zero-g tea pot.
    (and wondering why, in this age of instant powdered tea and Keurig tea)

  • pzatchok

    You do not make a ‘proper cup of tea’

    You get a cut of hot water with a lid on it and just place the bag inside it. You then shoot your cream or sweetener into it out of a squeeze bottle.

    If you do not get to vigorous it all stays pretty neat and clean.

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