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Space Science

Toxic Moondust Bounces Like A Cannonball 156

Jotii writes "A new NASA article says that moondust fetched to Earth by Apollo 17 is now being studied. From the article: 'Zen-like, he studies the a single mote of dust suspended inside a basketball-sized vacuum chamber for as long as 10 to 12 days.' Moondust is apparently very static, and bounces like cannonballs. Another article from NASA emphasizes the dust's toxicity: 'In some ways, lunar dust resembles the silica dust on Earth that causes silicosis, a serious disease.'"
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Toxic Moondust Bounces Like A Cannonball

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  • I for one, (Score:3, Funny)

    by SauroNlord ( 707570 ) on Saturday November 26, 2005 @04:58AM (#14117791)
    I for one welcome our statically bouncing moondust neighbours.
    • by xfletch ( 623022 ) on Saturday November 26, 2005 @06:22AM (#14117987) Homepage
      I for one welcome our statically bouncing moondust neighbours

      I think the poster has grasped the less than clear point that 'bouncing like cannonballs' means not bouncing at all. Perhaps 'bounces like watermelons' would have been better, but then again 'melons' and 'bouncing' in the same sentence may have distracted some of our younger readers...

      • by 1u3hr ( 530656 ) on Saturday November 26, 2005 @11:37AM (#14118764)
        I think the poster has grasped the less than clear point that 'bouncing like cannonballs' means not bouncing at all.

        Actually, the submitter seems to have mashed up the analogies in TFA to somethng unintellible.

        It says "In the lunar daytime, intense ultraviolet (UV) light from the sun knocks electrons out of the powdery grit. Dust grains on the moon's daylit surface thus become positively charged. Eventually, the repulsive charges become so strong that grains are launched off the surface 'like cannonballs,' says Abbas, arcing kilometers above the moon until gravity makes them fall back again to the ground."

        Note that the word "bouncing" does not appear anywhere.

      • All things being equal, a metal ball will bounce higher than a rubber one because the compression snap ends up being of greater energy... er... after dented when the bounce is initiated, the metal ball returns to its original shape faster, propelling it higher than a similar rubber ball. I figured the same would apply to cannon balls since they are metal (aren't they?)... I just don't get it... is it because cannon balls are so heavy that it appears all /.ers are in agreement that they don't bounce? Why do
    • " I for one welcome our statically bouncing moondust neighbours."

      what, they aren't going to try and tyranically rule us?
    • by Xyrus ( 755017 )
      Silicosis? Is that related to pneumonoultramicroscopicsiliconvolcanoconiosis?

      I finally got to use that word. :)

      ~X~
  • flubber (Score:4, Funny)

    by know1 ( 854868 ) on Saturday November 26, 2005 @04:58AM (#14117792)
    whee, it's flubber! i bet those scientists had lots of fun. that is a long time for somehing to bounce, but i would imagine in a vacuum with no air resistance any bouncy ball would go on for a long time
  • by lachlan76 ( 770870 ) on Saturday November 26, 2005 @04:58AM (#14117793)
    Have any of the astronauts who were on the moon missions suffered from damage because of this? No doubt they would be exposed to it at some point during the mission...
    • by Anonymous Coward
      Seeing as you need to inhale rather large amounts of it to do any harm.
      So yes, the astronauts had high exposure while walking around the moon's surface without any breathing apparti.
    • Yeah I'm totally sure the Apollo astronauts opened up their visors and took a deep breath of Luna's magnificent, polution free atmosphere, only to find they later have suffered from Silicosis and Lung Cancer worse than asbestos could have ever caused...

      or maybe they died from the extreme cold, lack of oxygen and mass radiation exposure.. I can't remember the details.
      • Comment removed (Score:5, Interesting)

        by account_deleted ( 4530225 ) on Saturday November 26, 2005 @05:18AM (#14117845)
        Comment removed based on user account deletion
        • TFA says the moondust is extremely statically charged, which if you've ever just combed your hair, you realize how much can stick to a comb with emmense strength.

          Now think about a particle 1/20th the size of most earthbound stuff with a much stronger static charge. It's going to stick very, very tightly to whatever its on.

          Besides, what's caught to the body of the suit isn't as much a deal as what was on the shoes, and they had covers, IIRC. Not to mention everyone was in quaranteen and extreme medical
          • Re: (Score:3, Interesting)

            Comment removed based on user account deletion
          • There was a science article about the properties of moondust (Wired?). Apparently, the moondust particles have lots of jagged edges, if not barbs as well, which provide plenty of sharp pointy bits to emit static charge, and allow it stick to anything and each other. This has the advantage that microwaving the particles will cause them to clump together.
        1. Space-suits can carry the dust on them
        2. Astronauts don't wear the suits from launch to landing
        • by andreMA ( 643885 ) on Saturday November 26, 2005 @06:23AM (#14117988)
          As I recall, either Armstrong or Aldrin noted a smell "like burnt gunpowder" in the LEM following the EVAs. This was attributed to the dust.

          As to health issues, isn't silicosis the result of chronic exposure? I doubt the dozen (18 if you count the guy in the CSM being exposed on the way home) folks with the most exposure were exposed to enough, for long enough, to have any impact.

          If/when we have a long-term presence on the moon, this may be an issue. I suspect one easily solved by taking a quick shower in the airlock on your way back in. Obviously you'd recycle the water, distilling it if need be to leave behind the dust. Though I suspect that in the presence of water and being allowed to sit a while, it might form a sludge that settles. Failing that, I'm sure there's something that could be added to bind it into a harmless solid.

          Filtering the air, electrostatic precipitation, etc. would also likely be a good idea.

          • D'oh

            The shower would be while suited (no doubt requiring a lot of testing of new suits for water resistance). Maintaining a high relative humidity inside would probably be helpful as well.

            • Underwater tests are already conducted, seeing as working underwater is the closest terrestrial condition to weightlessness possible...
          • by ozmanjusri ( 601766 ) <aussie_bob@hoMOSCOWtmail.com minus city> on Saturday November 26, 2005 @07:09AM (#14118095) Journal
            As to health issues, isn't silicosis the result of chronic exposure?

            Silicosis is the result of chronic exposure to crystalline silica, and it was believed that the illness was caused by mechanical irritation and subsequent scarring (plaques) of the lung tissues. Amorphous silica was considered to be safe since its rounded aspect meant it could be removed by the body's macrophages relatively easily.

            We do know now though, there is a form of acute silicosis which is caused by inflammation of the lung tissues in contact with large amounts of silica (chemical toxicity). The onset is much more rapid (weeks or months instead of years) but it is likely it will be a treatable illness where chronic silicosis is not.
    • by Anonymous Coward on Saturday November 26, 2005 @05:20AM (#14117850)
      Not only the silicosis issue, but the Moon is also unshielded from UV (and higher frequency) radiation. This tends to break up molecules on the surface of the dust and makes them very reactive.

      One of the worries on a Mars mission (similar UV situation to the Moon) is that if a persons skin comes in contact with rocks they will be burned (chemically). This is also the reason why it is extremely unlikely that life is observable in the first couple of millimeters of Martian soil. I would imagine that Moon dust has the same hazards.

      Of course if you are trying to breathe Moon dust you are either inside your capsule or have much greater worries that the chemical reactivity of the dust.
    • Another article from NASA emphasizes the dust's toxicity: 'In some ways, lunar dust resembles the silica dust on Earth that causes silicosis, a serious disease.'"

      Yeah, it's a good thing they had those breathers, or they'd have been looking at some serious OSHA violations.

      No doubt they would be exposed to it at some point during the mission...

      Seriously, the samples were placed into sealed containers to avoid contamination of the moon material with earth material. The moon material was quarantined, then sampl
    • The Apollo astronauts said that they did get exposed to the dust that was on their suits. Once they hopped bck into the ascent stage of the lunar lander, the dust floated everywhere. Once they reconnected with the command module, some of the dust blew in. They breathed the dust throughout the trip home.
    • Apollo 17 lunar module pilot Harrison Schmitt suffered hay fever [nasa.gov] due to all the moon dust floating around in the lunar module.
  • Lol. (Score:3, Insightful)

    by MrAnnoyanceToYou ( 654053 ) <dylan@dyRABBITla ... minus herbivore> on Saturday November 26, 2005 @05:02AM (#14117798) Homepage Journal
    Silica poisoning is something people who work with ceramics extensively occasionally get..... If you're working with the stuff while it's dry on a regular basis, you should probably wear a dust mask.

    Don't know if we've ever brought back enough dust to actually cause anyone harm.
    • Is that strictly considered "poisoning" or is it more "mechanical injury" on a small scale? The article summary was wrong on this, I think... not "toxic", but dangerous.

      --
      Lead is toxic, but the mechanical injury of being shot is the more immediate concern...

      • Re:Lol. (Score:3, Informative)

        Silicosis is caused by buildup of microscarring in the lungs from internally processing and removing microshards of essentially a silicate solid. Some glassworkers used to get it from grinding glass dry, too, so if you ever drill glass, keep the drill tip and growing hole in the glass wet.
  • by NitsujTPU ( 19263 ) on Saturday November 26, 2005 @05:03AM (#14117804)
    If this dust bounces like canonballs, then the NBA will be ALL OVER toxic moondust basketballs.
    • by Anonymous Coward
      i'm confused as i do not have cannonballs and therefore have never bounced one. is it saying that the dust does not bounce, and therefore bounces like a cannonball, which does not bounce; or do cannonball's actually bounce fairly well and the dust bounces well also??????
      • Re:Watch out NBA (Score:5, Informative)

        by Detritus ( 11846 ) on Saturday November 26, 2005 @08:23AM (#14118241) Homepage
        Cannonballs bounce nicely when fired from a cannon. I've read descriptions of American Civil War battles that noted how cannonballs gracefully bounced across the battlefield. Although fascinating to watch, they were still extremely dangerous to anyone in their path.
        • Cannonballs bounce nicely when fired very horizontally, but if dropped vertically they bounce little or not.
          • Re:Watch out NBA (Score:5, Informative)

            by sweetnjguy29 ( 880256 ) on Saturday November 26, 2005 @09:48AM (#14118418) Journal
            If everyone would RTFA, the actual quote is Eventually, the repulsive charges become so strong that grains are launched off the surface "like cannonballs" not "Moondust bounces like cannonballs" as the slashdot summary states.

            However, as the previous poster mentioned, cannonballs do in fact bounce. However, I doubt that it would be possible to actually see the bouncing cannon ball itself, as it is probably moving at least 300 m/s or so. (I imagine that most of the collisions were highly elastic...allowing a bounce) especially since archeologically recovered canonballs dont have too much damage to them. However, you could probably see the dust rising from where the canon ball is skipping...as well as the effect on any troops in the way. I remember watching a show on the Military Channel where they filmed different types of cannon shot...in slow motion...so you could see how the ball skipped/bounced and lost energy.

            • Re:Watch out NBA (Score:5, Interesting)

              by Perf ( 14203 ) on Saturday November 26, 2005 @12:05PM (#14118876)
              I think you are assuming too much...

              Personal accounts by a Civil War era soldier (my great grandfather) say that the cannon balls looked like softballs bouncing across the field. He said that you would think you could put your foot out and stop it, but if you did, you'd lose your leg.

              Also, when the light is right, I've seen 22 bullets in flight. (22 Long Rifle) I was a doubter until someone showed me.

              • Re:Watch out NBA (Score:2, Interesting)

                Personal accounts by a Civil War era soldier (my great grandfather) say that the cannon balls looked like softballs bouncing across the field. He said that you would think you could put your foot out and stop it, but if you did, you'd lose your leg.

                Of course, you know that a personal anecdote is bad logic, and thus bad science, since it is a well-known logical fallacy.

                However, I think your great-grandfather's story is very compelling and really cool...and matches what I saw on that tv show...although I

              • I've frequently seen 81mm mortor rounds in flight, generaly as they approach and pass their maximum ordinate (peak of flight), rifle bullets are extremely dificualt to see unless you are looking through binoculars or a spotting scope.
              • Same with watching a tire broken loose from a race car in an accident. They look like they're not going very fast, but they are, and they have a lot of KE in them from the speed they might be spinning at, and they're not light in the first place, so if it hits a human, it's not pretty. Now, add in the occaisional pieces of suspension and brake that can sometimes stay attached to them, also whirling at Cuisinart speeds...
    • Yes, but I wouldn't want to be one of the fans in the stands with all that dust flying all over the stadium. What a deadly game.
  • by KingSkippus ( 799657 ) * on Saturday November 26, 2005 @05:04AM (#14117806) Homepage Journal

    I think that if this study proves that moondust can be dangerous, any astronauts stationed to a moonbase should probably just stay inside. Or at least, cover their mouths while they're roaming around outside. No sense in risking your health by walking around outside on the moon without any kind of protection for your lungs.

  • by Datamonstar ( 845886 ) on Saturday November 26, 2005 @05:08AM (#14117818)
    Who the hell wants a big bouncing ball of toxic dust for X-mas?

    I'd be torn. Cool space dust... or the Xbox 360 that I asked for. Descisions, descisions!
    • Definitely go with the moon dust. At least it'll be a hundred times more valuable and something cool to show/threaten your friends with. Whereas the Xbox 360 will just overheat and die and can't be appreciated nicely without a grand being spent on a new TV.
    • Go with the moon dust. After the PS3 and Revolution come out, the moon dust will still be cool. ;-)

  • Why not just use static to get the dust off too?
    You could simply use static emitters in the lunar module to trap dust, just like a 5 billion duster.

    Cheaper alternative, stick a sign on the door that says: "Please remove your shoes before entering lunar lander."
  • by presidentbeef ( 779674 ) on Saturday November 26, 2005 @05:20AM (#14117848) Homepage Journal
    Don't cannonballs bounce similarly to how lead balloons fly...?
    • by Potato Battery ( 872080 ) on Saturday November 26, 2005 @05:52AM (#14117933)

      They tested it by firing it at a model of the USS Constitution carved out of a grain of rice. The moondust cannonballs were found to be much more effective at doing damage to the hulls of an armada of less-well crafted microscopic ships of war.

      I think the "cannonball" reference indicates the powers that be have let slip a little too much:

      • there is life on the moon
      • it has attained a level of technology roughly that of 16th century through 18th century Europe
      • they are very little
      • we are planning to fight them on their terms
    • I don't think they refer to it's mass (heavy balls don't bounce up because of mass&gravity) but to their (supposely similar) elasticity. Hard metal spheres when they collide in a pendulum style arrangement will carry on 'clicking' for a long time.
      • Re:I'm confused (Score:2, Informative)

        a ball of steel will actually bounce higher than a ball of rubber, as long as the surface it hits doesn't move or deform. This doesn't describe your average road ("boing" versuse "crunch") but with a giant slab of steel, the cannonball will bounce higher than the rubber.
        • Maybe... but is this also the case when:
          1.The balls have same sizes (and thus the rubber ball less mass)
          2.They bounce 'up' countering 1G of gravity. ?

          That's why I said (between parenthesis) that weight reduces the bouncing effect of a cannonball compared to a rubber ball.

          • tssk tssk tssk... you're like the greeks. (Simplistically) a bounce has a single parameter, efficiency. This is the proportion of kinetic energy lost in a bounce. a 50% efficient collision with a 1 gram rubber ball against the ground and a 1 ton steel ball against the ground will result in them going back up to the same height, ignoring air resistance.
  • by OBeardedOne ( 700849 ) on Saturday November 26, 2005 @05:21AM (#14117853) Homepage
    Last time I tried to bounce a cannonball I was thrown off the team.

  • by Wilson_6500 ( 896824 ) on Saturday November 26, 2005 @05:25AM (#14117869)
    Um... Does anyone know the chemical composition of this dust? How different is it from the stuff you'd find on Earth, chemically speaking? I don't care what it does, I care what makes it up.

    On a different note now, silica dust seems to me like it'd be basically glass or ceramic powder, and it makes intuitive sense that powdered glass would be very bad for the lungs. But couldn't any finely divided dust of materials with similar properties to silica be expected to cause a similar condition if inhaled over time? I'm thinking steel dust or granite powder, or something like that. It's not like asbestos, where the "toxicity" is really "carcinogenicity."

    In fact, calling the dust "toxic" makes it out to be a poison, when it's really more of a severe and persistent irritant. To call this or asbestos toxic seems a bit misleading and sensational--not to understate the dangers, but you want people to understand why things are dangerous, and in what way. Dimethyl mercury is toxic by contact; phosgene is toxic by inhalation; I think that both do more than just irritate.
    • by KingSkippus ( 799657 ) * on Saturday November 26, 2005 @05:42AM (#14117916) Homepage Journal

      Yes, TFA mentioned it specifically as quartz.

      "You could eat it and not get sick," [Russell Kerschmann, NASA pathologist] continues. "But when quartz is freshly ground into dust particles smaller than 10 microns (for comparison, a human hair is 50+ microns wide) and breathed into the lungs, they can embed themselves deeply into the tiny alveolar sacs and ducts where oxygen and carbon dioxide gases are exchanged." There, the lungs cannot clear out the dust by mucous or coughing. Moreover, the immune system's white blood cells commit suicide when they try to engulf the sharp-edged particles to carry them away in the bloodstream. In the acute form of silicosis, the lungs can fill with proteins from the blood, "and it's as if the victim slowly suffocates" from a pneumonia-like condition.

      Ew.

      The thing that makes moondust more bothersome that earth quartz dust is that the moondust is charged by UV rays, which causes it to be a lot more sticky than quartz dust is here. Also, the cannonball reference was to the dust flying up off the surface of the moon, which means that the astronauts' spacesuits (and moonbase, once we build one) will be covered from above and below in the stuff. It'll be hard to keep the stuff out if the astronauts come and go often, and once in, it can wreak havoc on their health over the relatively short period of time of a few months.

      • Wow, I totally missed that article.

        OK, so, from the article:

        Lunar dust, being a compound of silicon as is quartz, is (to our current knowledge) also not poisonous.

        So it _has_ silicon in it, and it's probably chemically similar to quartz. After a little google work, I turned up This [nasa.gov] presentation that outlines the stuff a little. It appears to be mostly silicon monoxide--similar in composition to silica, but not chemically the same. But, hell, just looking at those particles, they look "sharp edged,
    • On a different note now, silica dust seems to me like it'd be basically glass or ceramic powder, and it makes intuitive sense that powdered glass would be very bad for the lungs.

      Spinoza thought so!
  • by Shanep ( 68243 ) on Saturday November 26, 2005 @05:27AM (#14117871) Homepage
    Are all our moondust belong to them?
  • by Anonymous Coward
    "A new NASA article says that moondust fetched to Earth by Apollo 17 is now being studied. [...]"

    Well, all I can say is, it's about time!
  • WTF is this article about? Do they bounce or not? I think "bounce like cannonballs" was just a very poor attempt at sarcasm by the scientist. I don't think there's any story here at all really. But I guess that's why I read it first on Slashdot...
    • Y'know, it probably would have taken you less time to click on the article link and read the first six paragraphs, which would answer your question, than post it here. But I guess that's why we're seeing your comment on Slashdot...
  • by circletimessquare ( 444983 ) <circletimessquar ... m minus language> on Saturday November 26, 2005 @06:17AM (#14117981) Homepage Journal
    close your eyes and imagine a speck of dust bouncing like a cannonball...

    i understand the instinct that drives scientists to say things like it "bounces like cannonballs" for the sake of us average joes who don't talk in kilocuries and attonewtons and femtofarads

    however i would respectfully request that scientists attempting to talk in layman terms update their terminology to something after the civil war, as i don't think many of us average joes have seen any cannonballs bouncing around anywhere lately

    i mean what is "bounces like cannonballs" supposed to mean? the best mental image i can come up with is a bouncing bowling ball... which doesn't really bounce- is that the point? then why not just say "it doesn't bounce"

    does it make sense to say "the car drove off the highway at 80 mph and bounced off the tree like a cannonball" unless you're trying to write colorful fiction?
    • Re:layman-speak (Score:4, Informative)

      by KingSkippus ( 799657 ) * on Saturday November 26, 2005 @06:43AM (#14118031) Homepage Journal
      however i would respectfully request that scientists attempting to talk in layman terms update their terminology to something after the civil war

      God, that's funny.

      In NASA's defense, "bounces like a cannonball" was the submitter's phrase, not the article's. The article says:

      Eventually, the repulsive charges become so strong that grains are launched off the surface "like cannonballs," says Abbas, arcing kilometers above the moon until gravity makes them fall back again to the ground.

      This simile, while still perhaps antiquated, makes a lot more sense.

      /still imagining "bouncing" cannonballs...

  • Moondust is toxic (Score:4, Interesting)

    by brainwash ( 923821 ) on Saturday November 26, 2005 @07:15AM (#14118113)
    On the same NASA site, there's an article about the toxicity of moondust. It appears that because of its small particle size (10 microns), the moondust gets embedded into lungs, just like quartz used to do in the old mining days, causing silicosis.
    The astronauts did inhale some of the moondust, with effects similar to a hay fever.
    Not only that, but the dust is statically charged because of the Sun and lack of humidity, so it will stick to just about anything, causing abrasion.
    http://science.nasa.gov/headlines/y2005/22apr_dont inhale.htm [nasa.gov]
    There are plans to build a "microwave lunar lawn mower" that will melt the dust into something useful and stop it from bouncing.
    http://science.nasa.gov/headlines/y2005/09nov_lawn mower.htm [nasa.gov]
  • Toxic? Nonsense! (Score:4, Insightful)

    by YuppieScum ( 1096 ) on Saturday November 26, 2005 @07:20AM (#14118119) Journal
    Saying that moon-dust is toxic because it could cause silicosis is like saying water is toxic becuase you can drown in it.
    • Re:Toxic? Nonsense! (Score:3, Informative)

      by roman_mir ( 125474 )
      I actually read both articles in question and nowhere does it say that moondust is toxic. It does however say that Martian dust can be toxic in the second article [nasa.gov]. Here are the relevant quotes:

      Quartz, the main cause of silicosis, is not chemically poisonous: "You could eat it and not get sick ...
      Lunar dust, being a compound of silicon as is quartz, is (to our current knowledge) also not poisonous. ...
      Martian dust could be even worse. It's not only a mechanical irritant but also perhaps a chemical poison.
      • Some scientists suspect that the dusty soil on Mars may be such a strong oxidizer that it burns any organic compound such as plastics, rubber or human skin as viciously as undiluted lye or laundry bleach.

        The dust itself won't do much oxidizing unless it gets wet.

        Undiluted lye is FAR FAR WORSE than laundry bleach...

        If it doesn't get much warmer than -20 deg F at the equator, and the air is about as thin as on Mt Everest, don't you think that people will be in some form of bunnysuit out there anyways?

        Don't yo
  • Incidently... (Score:3, Informative)

    by Skiron ( 735617 ) on Saturday November 26, 2005 @07:56AM (#14118190)
    The Apollo 17 landing film is truly great to watch; the excitement in the astronauts voices shows what it really means for man to land on the moon:

    Landing at Taurus-Littrow [nasa.gov]
  • "individual dust grains returned by Apollo 17 astronauts in 1972 and the Russian Luna-24 sample-return spacecraft that landed on the Moon in 1976"

    Another government program that doesn't understand the concept of turnaround time. Demand efficiency, or farm it out to the free market!

    (Ha ha, only serious.)
  • I don't know what this story is about, but I know the next song I write is bound to have the line "Toxic Moondust Bounces Like A Cannonball." Thanks, and pass the bong, taco.
  • by kronocide ( 209440 ) on Saturday November 26, 2005 @11:24AM (#14118715) Homepage Journal
    As has been pointed out in a previous post, "calling moondust toxic because it can cause silicosis is like calling water toxic because you can drown in it." Moondust, it seems clear, also does not "bounce like a cannonball." Nothing bounces like a cannonball, just like nothing "oscillates like a cloud," or "crows like a football." In the light of these observations, I'm not quite convinced that it really is dust, or that it comes from the moon. Anyway, I'd like to nominate this for the Worst Headline 2005 Award.
  • by xs650 ( 741277 ) on Saturday November 26, 2005 @12:33PM (#14118987)
    "A new NASA article says that moondust fetched to Earth by Apollo 17 is now being studied."

    Now I don't feel so bad about how long it takes me to get around to finishing projects.

  • Toxic Moondust Bounces Like A Cannonball

    Cannonballs bounce?
  • Another article from NASA emphasizes the dust's toxicity: 'In some ways, lunar dust resembles the silica dust on Earth that causes silicosis, a serious disease.'

    . . . It was as if millions of personal-injury lawyers [ferrarolaw.com] suddenly cried out in ecstasy [acr.org] and were suddenly enriched [provostumphrey.com].

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