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Astronauts Attach Mannequin to Outside of ISS

Posted by michael on from the open-the-pod-bay-doors-hal dept.

lhouk281 writes "According to Space.Com, astronauts have attached a mannequin to the outside of the International Space Station to study the effects of radiation on the human body. The mannequin contains actual bone surrounded by simulated organs and synthetic skin, with sensors studded throughout." There's another story that has detail on how the spacewalk went: a suit malfunction caused the spacewalk to end prematurely.

10 of 194 comments (clear)

  1. Hmm... by venomix · · Score: 4, Interesting

    That synthetic skin would have to be really strong for this thing not to blow up due to low pressure, wouldn't it?

    1. Re:Hmm... by Tango42 · · Score: 4, Interesting

      Indeed, you wouldn't freeze, because there's nowhere for the heat to go. Usually things lose heat by conduction (and convection), which is fast, in space you have only radiation, which is much slower. (However, if you were walking around on the dark side of the moon you might lose heat throught your feet to the ground)

    2. Re:Hmm... by AlecC · · Score: 5, Interesting

      Who would have thought that the sun heated the earth through convection eh?

      The sun is about 6000K: you are about 300K. Since radiation goes as the fourth power of temperature, the sun is about 20^4 times as good a radiator as a human body.

      You would, of course, eventually freeze in space. But it would be many hours after you suffocated.

      --
      Consciousness is an illusion caused by an excess of self consciousness.
    3. Re:Hmm... by no+longer+myself · · Score: 5, Interesting
      OK, so at the risk of showing off my ignorance (I know... already too late.) Here's a question I've been pondering for some time now:

      Obviously if you just abruptly depressurised a person, they'd form nitrogen bubbles in their blood and contract the bends, and probably die. But what if... And this is a big morbid what if... What if you slowly depressurised a person while having an oxigen mask securely (but comfortably) attached to their face? Could you eventually bring a human body down to zero atmospheres and they'd be able to stay alive?

      If not, what would be the lowest limit?

    4. Re:Hmm... by Anonymous Coward · · Score: 5, Interesting

      I did research subjects related to this for a discussion on a forum a few years ago. Both the US and Russians had astronauts who suffered 'explosive decompression' down to almost no atmospheres. One was due to a large rip in a mock spacesuit, and the other due to decompression of the entire capsule they were in. Both survived, despite being decompressed for up to 45 seconds. They lost consciousness very quickly, after 10-15 seconds, and had no ill effects afterwards.

      One of the problems with long term decompression is that blood vessels near the surface expand greatly... suck on the inside of your arm for an example - it happens bodywide. Not a problem for a few minutes, but it will end up bruising tissue badly after long term exposure.

    5. Re:Hmm... by lxs · · Score: 4, Interesting

      if you breathe 100% oxygen, you'd still have to have about 1/5th of an atmosphere of gas in your lungs to function properly (since the human body is designed for ~20% oxygen @ 1atm) you may be able to go a little lower than that but that's still an awful lot of pressure to contain, unless you start breathing liquids, which AFAIK has only been tested at high pressures, but might equally provide advantages at near vacuum .

      The other problem would be evaporation. Your sweat would boil off in a vacuum, which would leave you extremely cold and with very dry skin.

      And if you're in space, prepare yourself for the ultimate in sunburn.

      Needless to say, I won't be volunteering for tests.

  2. it'll be... by nomel · · Score: 3, Interesting

    it'll be interesting to see what space debris does.

    1. Re:it'll be... by charboy1 · · Score: 5, Interesting

      Let's hope it does nothing, as in no space debris hits the space station.

      Actually space debris and meteoroids hit ISS quite often. So far they have been very small and as you say hopefully it remains that way. ISS is designed to withstand impacts up to a certain size and probability by placing an additional wall outside the pressurised module to absorb and diffuse the impact. Learn more about the general policy in Protecting the Space Station from Meteoroids and Orbital Debris. Or see a short explanation of the Meteorid / Debris Protection System for Node 2.

      - charboy

  3. Cool idea by thogard · · Score: 4, Interesting

    Now if the ISS was high enough to make this expierment useful, then it would be a great idea but the ISS is in a very low orbit well inside the protective magnetosphere of earth. While there isn't enough atmosphere to protect anyone from small particles, there is enough to slow its orbit down.

  4. True, but Radiation's still surprisingly effective by Saltation · · Score: 5, Interesting

    Yeah, I've always thought this too. And it's mostly right -- you certainly will never see that cringe-worthy bad-sci-fi staple of liquids "freezing and boiling at the same time."
    But interestingly, I discovered just last week if you take a spaceship out of direct sunshine, it starts to lose heat pretty substantially. One of the first space stations (I forget which) had its heatshield buggered up by over-early deployment and it started to overheat dramatically. An astronaut pushed an umbrella arrangement out an airlock to provide cover from the sun, and the temperature "immediately began to drop" (ok, a little obvious) and was within the expected range within a day. I saw this on "The Planets" TV show which was excellently researched, so I'd assume this was pretty valid.

    In summary, radiation of heat seems to still provide a pretty good cooling mechanism in space, despite being much slower than conduction.

    So while you'll be relieved to know you'll asphyxiate in comfort and warmth, you'll eventually become a corpsicle if you stay out of the sun(light).

    cheers, Sal

    --
    Sal

    Writings: saltation.blogspot.com
    Wravings: go-blog-go.blogspot.com