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Astronauts Attach Mannequin to Outside of ISS
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.
I believe thats a myth.
There just isn't enough pressure in the human body to make it explode in a vacuum like you see in sci-fi films.
Here's how they do it:
The space mannequin's "skin" is a coat of multi-layer insulation containing thermo-luminescence dosimeters, detectors that glow in proportion to the amount of radiation they receive. Those detectors are distributed about every inch (2.5 centimeters) throughout the torso to give scientists a depth-dose profile of radiation exposure. (...) Encapsulating the Phantom torso is a protective canister of carbon fiber-reinforced plastic.
Read the truth here.
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
Maybe I should've posted more of the text -
Itself replete with radiation sensors, the canister's interior supports an oxygen environment to better mirror its human space suit counterparts.
Also, this is just the torso, not an entire dummy. No arms or legs.
If you missed the 60s because you weren't born, here's a good link : http://www.apolloarchive.com/
Now that high definiton microcams exist, I wish the astronauts would broadcast a little more...
Here's the mannequin. I seriously doubt that they use human bones, since animal bones of comparable size would interact with radiation in the same way.
I'm not sure what you're suggesting with ground-up bones... an ossified version of particle board?
That synthetic skin would have to be really strong for this thing not to blow up due to low pressure, wouldn't it?
Actually the phantom is made up of several slices, about 30, stacked on top of each other on a central rod. (Think of the old baby toy.) The main material of the phantom is called RANDO(R). It's embedded with bits of bone and polyurethane to simulate organs. I believe the "natural bone" is ground up and reshaped into bone like structures.
To answer your question, there's really nothing to "blow up" during depressurisation. All of the phantom slices are solid with lots of cut-outs for radiation detectors.
- charboy
I'm sorry but evaporation always leads to heat loss. If you evaporate a fixed number of grammes of a given liquid, you lose a fixed number of joules. This heat comes from the breaking of vanderwaals forces between molecules, not from acting against ambient pressure.
other way round, actually.
the human's proportion of surface area to volume is much much higher than a space ship. as you make objects larger, the surface area tends to increase in square proportion, the volume in cubic proportion. so the ratio of surface-area to volume decreases as things get bigger. cats freeze quicker than humans, humans freeze quicker than elephants (not least 'cos they're buggers to get into the fridge).
i could be a smartarse at this point, and point out that the spaceship, being comprised primarily of metal in its solid state, is in fact already frozen. but i won't.
--
Sal
Writings: saltation.blogspot.com
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You really need to learn some physics.
Some points to consider:
1. the molecules don't 'know' whether there is a vacuum or not. They just feel an electrostatic force due to each other's proximity.
2. temperature and heat are two different things.
3. The boiling point is the temperature at which the vapour pressure of the liquid equals the ambient pressure.
When a liquid reaches boiling point, evaporation goes much faster (since it can occur throughout the liquid not just at the surface which leads to great heat loss, which means that the temperature cannot rise any further. So at lower pressures, the boiling point is lower.)
4. It's saturday and sunny out (at least around here it is), so instead of arguing about physics, it's far more fun to go outside.
The outer container of the Matroshka experiment is made by DTM, formerly known as Ferrari S.p.A Space Division. The DTM logo is visible on the outside of the composite container. This composite, Carbon Fibre Reinforced Plastics, is similar to those used for the better-known Ferrari Formula 1 cars (although a special mould was made to get the shape of the Matroshka container since not too many cars have that shape). The container is leak tight to maintain an atmosphere inside until it's brought back inside ISS (scheduled in ~1 year).
'Dummies test you' indeed :p
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."
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Ahem. Someone needs to learn about something called the triple point. At that temperature & pressure, the substance will exist in all three phases and be able to shift between them.
From the wiki link above:
"For example, the triple point temperature of water is exactly 273.16 kelvin (about 0.01 C) and the triple point pressure is 611.73 pascal (ca. 0.006 bar)."
This is high school physics, not sci-fi, man...
I hate to be a party pooper (okay so I lied) but given that it's all about equalization of pressure, what's the difference, whether you go from suck to blow, or blow to suck?
It has to do with what force is acting on the gas to make it go from a pressurized area into a vacuum. Does the vacuum exert some kind of attractive force on the gas to pull it out? If so, then it would suck. Or is the force caused by the atoms of the gas colliding and pushing the other atoms away? If so, then it would blow.
Just like when you blow out a candle, the low pressure of the surrounding room doesn't magically suck the air out of you -- it is you creating a higher pressure and consequently blowing which is the cause. Technically speaking, there isn't such a thing as 'sucking' in physics. When you use a straw to sip a drink, you create a low pressure area in your mouth (and, by extension, the straw) and it's the higher pressured surroundings which pushes the drink up the straw.
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