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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.
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.
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?
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.
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
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