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Toxic Moondust Bounces Like A Cannonball

Posted by Zonk on from the all-i-want-for-christmas dept.

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.'"

6 of 156 comments (clear)

  1. Previous Information? by lachlan76 · · Score: 4, Informative

    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...

    1. Re:Previous Information? by Anonymous Coward · · Score: 4, Informative

      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.

    2. Re:Previous Information? by andreMA · · Score: 4, Informative
      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.

    3. Re:Previous Information? by ozmanjusri · · Score: 4, Informative

      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.

      --
      "I've got more toys than Teruhisa Kitahara."
  2. Re:Watch out NBA by Detritus · · Score: 4, Informative

    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.

    --
    Mea navis aericumbens anguillis abundat
  3. Re:Watch out NBA by sweetnjguy29 · · Score: 5, Informative
    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.