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Apparently a 1.5mm puncture due to a meteor/debris strike in the Russian Soyuz MS-09 module. More information: http://blogs.esa.int/alexander-gerst/2018/08/30

by snsr 8y ago

Apparently a 1.5mm puncture due to a meteor/debris strike in the Russian Soyuz MS-09 module. More information: http://blogs.esa.int/alexander-gerst/2018/08/30/slow-leak-detected-aboard-space-station/ http://blogs.esa.int/alexander-gerst/2018/08/30/slow-leak-de... https://twitter.com/RussianSpaceWeb?ref_src=twsrc%5Egoogle%7Ctwcamp%5Eserp%7Ctwgr%5Eauthor https://twitter.com/RussianSpaceWeb?ref_src=twsrc%5Egoogle%7... http://www.russianspaceweb.com/soyuz-ms-09.html#leak http://www.russianspaceweb.com/soyuz-ms-09.html#leak

village-idiot 8y ago
Makes sense. A manufacturing defect in a Soyuz would be extremely surprising, they have a very well respected safety record.
sctb 8y ago
Thanks! We've updated the link from https://www.independent.co.uk/life-style/gadgets-and-tech/news/nasa-international-space-station-leak-iss-latest-alarm-soyuz-module-a8514291.html https://www.independent.co.uk/life-style/gadgets-and-tech/ne....
ambicapter 8y ago
Does that mean there is a little meteor hanging out somewhere in the module?
- theothermkn 8y ago
  At the typical velocities for this kind of impact, probably not. At these speeds, computer analyses ignore the solid properties of the colliding objects, modeling them as liquids, instead. (The shear resistances is just not relevant, and everything liquefies from the heat from the impact. Even that heat loss is negligible in terms of the total energy of the collision.) Most likely, there would be fragments of the impactor and the hull, mixed together with each other and oxidized with the station air, floating about. I won't risk speculating about the fragment size, other than to say it would be pretty dang small. (I'm leaning toward "powder," but personally wouldn't rule out either "grit" or whatever "finer than powder" is.)
  - deleted 8y ago
    [deleted]
  - acomjean 8y ago
    >or whatever "finer than powder" silt. if its even smaller its clay.
    - deleted 8y ago
      [deleted]
  - BrandonMarc 8y ago
    So the astronauts have breathed the meteor into their lungs? Funky ...
    - da_chicken 8y ago
      They're breathing far more dead skin. So are you, though.
      - w-ll 8y ago
        Yes, but that's organic and pretty normal. Aren't meteors and say moon dust dangerous because its very sharp and jagged?
        UpshotKnothole 8y ago
        Once it’s flashed to a plasma and turned into sub-micron dust? Probably not. The danger if there is any would be if the remaining particulates (assuming it wasn’t mostly reduced to heat, light and some basic elements) are friable.
      - maxxxxx 8y ago
        I would expect much more stuff to be in the air under zero gravity. On earth dust will settle on the ground but I assume in the ISS it will keep floating around.
      - 8y ago
- jccooper 8y ago
  MMOD impacts tend towards "vaporize" rather than "puncture". That's how (and why) a Whipple shield works.
  - greglindahl 8y ago
    The Wikipedia article on the topic https://en.wikipedia.org/wiki/Whipple_shield https://en.wikipedia.org/wiki/Whipple_shield mentions that the ISS has 100 different kinds of shields on various parts of it -- presumably Soyuz doesn't have one thanks to its quite different launch and re-entry needs.
    - jccooper 8y ago
      Soyuz wouldn't have much. Good thing it's in the orbital module; there are much more problematic places for a hole. MMOD protection for visiting vehicles is actually a bit tough; they are on orbit for quite a while but have constraints around shielding. Both the new Boeing and SpaceX vehicles have had problems achieving high enough statistical survivability rates, mostly due to MMOD strikes. (Soyuz probably wouldn't pass those criteria either, but it's not asked to.)
kevindqc 8y ago
How does it not happen more often?
- Retric 8y ago
  ISS travels at a very low orbit which the earth’s atmosphere does a great job of keeping clean. They occasionally manover around anything large enough to be a significant issue. On to of that space is huge and largely empty even at the speed they are traveling. The ISS is also designed to take a hit and can generally survive similar impacts without issue.
- antonvs 8y ago
  Micrometeoroid impacts happen fairly regularly, but they're usually not energetic enough to make a hole. For example, there was a instance in 2012 where one hit a window: http://www.spacesafetymagazine.com/space-debris/kessler-syndrome/micrometeroid-hit-iss-cupola/ http://www.spacesafetymagazine.com/space-debris/kessler-synd... But as that incident shows, such impacts are often relatively benign - in that case, they didn't even need to replace the outer layer window. The hull is reinforced with four or five layers of shielding - the above article has a nice diagram: https://i2.wp.com/www.spacesafetymagazine.com/wp-content/uploads/2012/06/MMOD-typical-shields.jpg https://i2.wp.com/www.spacesafetymagazine.com/wp-content/upl... This means the usual consequence of a micrometeroid impact is pitting of the outer layers that may not even be noticed. For larger objects that present a serious danger, the US Space Surveillance Network attempts to track them and predict "conjunctions" with a zone around the ISS which extends 2km above and below it, and 25 km in each direction on the orbital path. Anything that's expected to intersect with this zone is analyzed and may result in the station being moved to get out of the way. These are mostly due to space junk of human origin. In 2013, there were at least ~70 of these "conjunction notifications", although this results in only about one move of the station per year, on average. There's a description of how these cases are handled at https://arstechnica.com/science/2013/07/how-nasa-steers-the-international-space-station-around-space-junk/ https://arstechnica.com/science/2013/07/how-nasa-steers-the-... : > "Any object with between a 1-in-10,000 and 1-in-100,000 chance of colliding with the station meets the "yellow" threshold. Flight rules say that the station must be moved out of the way in response to a yellow threshold object unless such a move results in a mission impact—"Like, if we do the burn, we're going to miss an opportunity to launch a Soyuz, for instance," explains Parris. "Do we delay the Soyuz, or do we do the maneuver?" A "red" threshold is assigned to any collision with a likelihood of between 1 (in other words, absolutely certain) and 1-in-10,000. Flight rules are more strict for maneuvers in response to red threshold objects: the station is always moved for a red threshold object, regardless of mission impact, unless a maneuver represents more risk than not maneuvering (for example, if there's a piece of equipment that's damaged on the ISS and a maneuver would exacerbate that damage)." This doesn't help in the case of meteor showers, where the Earth is travelling through a zone full of small debris, typically caused by the trail of a comet. In those cases, the station has to rely on its shielding, but the debris sizes in those cases are almost all within the limits that the shielding can handle.
Romanulus 8y ago
According to Russian sources, the problem was found in the Habitation Module of the Soyuz MS-09 spacecraft, where the crew detected two small cracks, reaching 1.5 millimeters in size. Alexander Gerst apparently first discovered the leak.
- Tuna-Fish 8y ago
  Not only first discovered. The first temporary patch was Gerst's finger.

by snsr 8y ago

village-idiot 8y ago

Makes sense. A manufacturing defect in a Soyuz would be extremely surprising, they have a very well respected safety record.

sctb 8y ago

Thanks! We've updated the link from https://www.independent.co.uk/life-style/gadgets-and-tech/news/nasa-international-space-station-leak-iss-latest-alarm-soyuz-module-a8514291.html https://www.independent.co.uk/life-style/gadgets-and-tech/ne....

ambicapter 8y ago

Does that mean there is a little meteor hanging out somewhere in the module?

theothermkn 8y ago
At the typical velocities for this kind of impact, probably not. At these speeds, computer analyses ignore the solid properties of the colliding objects, modeling them as liquids, instead. (The shear resistances is just not relevant, and everything liquefies from the heat from the impact. Even that heat loss is negligible in terms of the total energy of the collision.) Most likely, there would be fragments of the impactor and the hull, mixed together with each other and oxidized with the station air, floating about. I won't risk speculating about the fragment size, other than to say it would be pretty dang small. (I'm leaning toward "powder," but personally wouldn't rule out either "grit" or whatever "finer than powder" is.)
- deleted 8y ago
  [deleted]
- acomjean 8y ago
  >or whatever "finer than powder" silt. if its even smaller its clay.
  - deleted 8y ago
    [deleted]
- BrandonMarc 8y ago
  So the astronauts have breathed the meteor into their lungs? Funky ...
  - da_chicken 8y ago
    They're breathing far more dead skin. So are you, though.
    - w-ll 8y ago
      Yes, but that's organic and pretty normal. Aren't meteors and say moon dust dangerous because its very sharp and jagged?
      - UpshotKnothole 8y ago
        Once it’s flashed to a plasma and turned into sub-micron dust? Probably not. The danger if there is any would be if the remaining particulates (assuming it wasn’t mostly reduced to heat, light and some basic elements) are friable.
    - maxxxxx 8y ago
      I would expect much more stuff to be in the air under zero gravity. On earth dust will settle on the ground but I assume in the ISS it will keep floating around.
    - 8y ago
jccooper 8y ago
MMOD impacts tend towards "vaporize" rather than "puncture". That's how (and why) a Whipple shield works.
- greglindahl 8y ago
  The Wikipedia article on the topic https://en.wikipedia.org/wiki/Whipple_shield https://en.wikipedia.org/wiki/Whipple_shield mentions that the ISS has 100 different kinds of shields on various parts of it -- presumably Soyuz doesn't have one thanks to its quite different launch and re-entry needs.
  - jccooper 8y ago
    Soyuz wouldn't have much. Good thing it's in the orbital module; there are much more problematic places for a hole. MMOD protection for visiting vehicles is actually a bit tough; they are on orbit for quite a while but have constraints around shielding. Both the new Boeing and SpaceX vehicles have had problems achieving high enough statistical survivability rates, mostly due to MMOD strikes. (Soyuz probably wouldn't pass those criteria either, but it's not asked to.)

kevindqc 8y ago

How does it not happen more often?

Retric 8y ago
ISS travels at a very low orbit which the earth’s atmosphere does a great job of keeping clean. They occasionally manover around anything large enough to be a significant issue. On to of that space is huge and largely empty even at the speed they are traveling. The ISS is also designed to take a hit and can generally survive similar impacts without issue.
antonvs 8y ago
Micrometeoroid impacts happen fairly regularly, but they're usually not energetic enough to make a hole. For example, there was a instance in 2012 where one hit a window: http://www.spacesafetymagazine.com/space-debris/kessler-syndrome/micrometeroid-hit-iss-cupola/ http://www.spacesafetymagazine.com/space-debris/kessler-synd... But as that incident shows, such impacts are often relatively benign - in that case, they didn't even need to replace the outer layer window. The hull is reinforced with four or five layers of shielding - the above article has a nice diagram: https://i2.wp.com/www.spacesafetymagazine.com/wp-content/uploads/2012/06/MMOD-typical-shields.jpg https://i2.wp.com/www.spacesafetymagazine.com/wp-content/upl... This means the usual consequence of a micrometeroid impact is pitting of the outer layers that may not even be noticed. For larger objects that present a serious danger, the US Space Surveillance Network attempts to track them and predict "conjunctions" with a zone around the ISS which extends 2km above and below it, and 25 km in each direction on the orbital path. Anything that's expected to intersect with this zone is analyzed and may result in the station being moved to get out of the way. These are mostly due to space junk of human origin. In 2013, there were at least ~70 of these "conjunction notifications", although this results in only about one move of the station per year, on average. There's a description of how these cases are handled at https://arstechnica.com/science/2013/07/how-nasa-steers-the-international-space-station-around-space-junk/ https://arstechnica.com/science/2013/07/how-nasa-steers-the-... : > "Any object with between a 1-in-10,000 and 1-in-100,000 chance of colliding with the station meets the "yellow" threshold. Flight rules say that the station must be moved out of the way in response to a yellow threshold object unless such a move results in a mission impact—"Like, if we do the burn, we're going to miss an opportunity to launch a Soyuz, for instance," explains Parris. "Do we delay the Soyuz, or do we do the maneuver?" A "red" threshold is assigned to any collision with a likelihood of between 1 (in other words, absolutely certain) and 1-in-10,000. Flight rules are more strict for maneuvers in response to red threshold objects: the station is always moved for a red threshold object, regardless of mission impact, unless a maneuver represents more risk than not maneuvering (for example, if there's a piece of equipment that's damaged on the ISS and a maneuver would exacerbate that damage)." This doesn't help in the case of meteor showers, where the Earth is travelling through a zone full of small debris, typically caused by the trail of a comet. In those cases, the station has to rely on its shielding, but the debris sizes in those cases are almost all within the limits that the shielding can handle.

Romanulus 8y ago

According to Russian sources, the problem was found in the Habitation Module of the Soyuz MS-09 spacecraft, where the crew detected two small cracks, reaching 1.5 millimeters in size. Alexander Gerst apparently first discovered the leak.

Tuna-Fish 8y ago
Not only first discovered. The first temporary patch was Gerst's finger.