Survival in Space Unprotected Is Possible, Briefly (2008) | Hacker News Reader

Survival in Space Unprotected Is Possible, Briefly (2008)

scientificamerican.com

36 pointsThevet37 comments

This kind of illustrates that it's not that your blood boils or anything crazy like that, but rather that without external pressure, your body relies on your squishy flesh to hold the internal pressures in check. So you'll get a full-body hickey/swelling and the bends (though deep sea divers can, of course, suffer far worse since their internal pressure can be multiple atmospheres). If you've any exposed mucus membranes, expect them to off-gas and to start to freeze on the surface.

But all that takes time to really set in, so you've got a minute or so before you're really hurt. By that time, your real problem is simply that you've stopped breathing, which turns out to be a big deal.

Remember: vacuum is first and foremost an asphyxiant!

(Re asphyxiant, here's my favorite story on the topic: http://www.sciforums.com/threads/vacuum-pockets-and-safety-n... )

> By that time, your real problem is simply that you've stopped breathing, which turns out to be a big deal.

A really hypothetical scenario: but suppose for a moment an astronaut's is floating around, the suit has ripped open, oxygen within it is pretty much at nil, and unable to return in time. Would it be possible to bring a breathing apparatus(i.e. small oxygen tank) out to the astronaut to keep him/her breathing a bit longer?

You can live on a partial pressure of about 0.15 atm of oxygen. Less than that and your blood will lose oxygen as it passes through your lungs. So the tank works if the pressure is high enough.

RE your favourite story, I'm just waiting for someone with experience in this topic to point out here that vacuum pockets are actually a real thing under some conditions, and even maybe that those "safety nazis" were actually justified. Hanging out on HN I've seen many cases where something derided by people turns out to actually be true. :).

>By that time, your real problem is simply that you've stopped breathing, which turns out to be a big deal.

With some training holding your breath for 3 minutes is doable for anyone, and the record is something like 8-9 minutes..

You're right, but one of the main issues is that you probably don't have enough strength in your lip muscles and throat to keep the air in without outside pressure. A single ATM of pressure is easy to leak, and your body is undergoing some real nasty expansion problems; As the sibling commenter notes, too, holding your breath is likely dangerous, as your internal chest cavity may not be able to apply enough compressive force to hold the air in. (And microscopically your lung will try to inflate excessively, leading to internal bleeding, I think.)

There's a really cool idea for a spacesuit that's basically just a fabric wet suit that's just really compressive (via electromuscles or cinched bands or w/e). That way your body gets the ability to hold onto the gas in your lungs without the risk of your lungs attempting to expand out your gut and throat.

It's an interesting idea though: what if you could train your abdomen and chest to compress a lung full of air in a vacuum? Then you just gotta keep your mouth and nose shut somehow. (It'd be really difficult - it'd take a force like trying to inflate a car tire with your mouth. Possible, but seems hard.)

According to the article, holding your breath in a vacuum is not wise.

There was a notable incident in the 1960s where a NASA spacesuit technician named Jim LeBlanc survived an accidental (but brief) depressurization. There's a YouTube video describing the accident which includes film of the accident itself: https://www.youtube.com/watch?v=KO8L9tKR4CY.

What a great video, thanks for the link.

I remember reading an Arthur C. Clarke book where a space liner has lost their engines and their airlocks. The protagonist on the military rescue ship decides to do something drastic: blow up the space liner.

They seal the people into groups of 20 in separate cabins, and then they detonate small charges to puncture each cabin at a time. Their ship is positioned right next to the liner, with utility cords leading straight to the airlock. Clarke took this opportunity to explain that you don't freeze and explode in space, losing oxygen is the main problem. But also for that reason--- don't hold your breath when you're about to be exposed to vacuum, that's just a good way to rupture your lungs from the pressure.

This sounds like the end of Earthlight [1] (the novel, not the short story). However, it was the space liner rescuing the crew of the military ship in this case. The ability to evacuate the crew of the military ship without spacesuits is an important plot point, or at least a dramatic one.

Anyway, Clarke was apparently convinced that humans could survive a brief exposure to vacuum at least as early as 1955.

[1] https://en.wikipedia.org/wiki/Earthlight

Does this mean we might be ok on a 70 degree f [1] Mars with just a breathing mask? Especially if you're covering the mucus membranes.

1 https://en.m.wikipedia.org/wiki/Climate_of_Mars

I think the movie Event Horizon got it right. For anybody who hasn't seen it, someone is ejected out into Space. He's saved within about a minute. Though, he definitely suffers internal bleeding and other damages, he survives.

Caution: Event Horizon is also one hell of a mind-fucking horror movie. It's not for the weak-minded. Liberate tuteme ex inferis. You have been warned.

I went to see Event Horizon in the cinema when it first came out, with a couple of schoolfriends. There was an oldish couple in front of us, maybe in their 50s, possibly expecting a repeat of 2001.

Eventually the film finished, and we all got up, slightly dazed - couple included. The woman said to the man, with pursed lips - "Next time, I'm picking the film" :)

The drive home was about 40 minutes, and my friends and I were silent the whole way. But I'm sure if I saw it again, it would seem adorably tame.

I watched it on TV, late at night, as a kid. I remember barely being able to fall asleep out of fear, and I think it took a week for the effects of this movie to wear off. I'm older now and I've seen enough sad, scary and disrupting movies that it doesn't affect me anymore, but I'm pretty sure that if I tried to show it to my SO, I'd have my own Event Horizon right there in the apartment.

EDIT: I also had the "next time I'm picking the movie" moment after I took my then-girlfriend to see Prometheus. The TED2023 trailer looked so cool and I didn't realize it's a prequel to Alien...

Lol. Yes. I remember doing the same when it came out. Went to see it when I was in high school with some friends. I felt literally physically exhausted (and dazed, as you describe) after I walked out of the theater. We were all expecting an interesting sci-fi movie, not a disturbing horror movie.

While some aspects of that scene do seem to line up with the article, others don't.

For example, if the timeline of the movie is to be believed, the crew member is only exposed to a vacuum for about 10 or 15 seconds before his eyes seem to bleed massively or explode (actually, an apparent plot hole -- only a few seconds later, he's seen without any blood around his eyes). The article suggests that this wouldn't happen.

At the end of the day, Event Horizon was a pretty gory horror movie and they obviously took a lot of liberties in depicting depressurization.

This is how the astronaut in 2001: A Space Odyssey manages to get back on board the main ship.

To offer another sci-fi example, it's how two pilots of an experimental spacecraft in the TV series Stargate SG-1 were rescued when the spacecraft rapidly traveled away from Earth and locked them out of pretty much everything except ejecting from the craft. Their rescuers were waiting in a nearby spaceship to scoop them out of the vacuum of space.

Im really disturbed by the scientists that tortured dozens of dogs and chimps in vacuums.

Almost everything we know on the topic came from those dogs and the people who suffered accidents. It's the really unpleasant side of industrial and extreme environment danger: intuition just isn't enough to make big decisions on. The alternative is learning through trial and error, and industrial accidents teach us that is enormously bloody, expensive, and reactionary.

If it helps, every major write-up on the topic talks about what the dogs went through. A high price was paid, but they aren't forgotten nor did they suffer in vain - and most made a full recovery in fairly short order. You can be sure countless lives across space exploration will be saved because we'll know who can be saved and what's needed to bring them back.

I'm disturbed by their choice to use dogs of all animals. And especially chimps, which are very very close to humans. I'm disturbed that the experiment needed to be done 100's of times. The first few times might be understandable, but what do you really learn from throwing the 125th dog into the vacuum chamber?

And I'm sure this will be an unpopular opinion, but I don't believe this specific experiment needed to be done at all. Really, what did we learn? That bad things happen when you are exposed to a vacuum? No shit. It's at best interesting. But you'd be really hard pressed to find any practical application of this knowledge.

I've never been against animal experimentation before. I was always uncomfortable with it, but I just accepted the standard argument that it's necessary, and never looked too closely into the actual details. But something about this just went over the line, especially the horrific detailed description of the dogs and chimps suffering.

For what it's worth a lot of people agree with you and so the rules about vivisection are much stricter now.

There are probably people on HN who work with animals who can talk about how easy / hard it would be to perform this kind of testing on dogs in the EU / US today.

I think this is the actual study:

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/1966000...

I fundamentally dissagree that it was trivial, but I worked on large vacuum systems and feel a bit close to the topic. But I also fundamentally agree that the experimentation was barbaric and cruel. But... I also don't see how we could have worked around it. I hope it's some consolation that they never doubly-exposed the dogs; I'm actually surprised that wasn't attempted.

Unshielded hard vacuum is horrific. The problem isn't that it's awful - that's obvious - but exactly how does it affect the body? (I've sealed a hole with my hand and got a hickey, but I've never been immersed in it.) Even today, studying things in a vacuum is difficult; it's always behind a think layer of material that's hard to observe through, and even with cleverness you're testing through the neck of a bottle or only looking back on data logged by some gizmo. And there are a lot of confounding variables; narrowing the time-to-unconciousness/death was the most critical, and each test batch needed multiple samples to make sure no data was wasted. One note that came out was that it seems clearly better to recompress with pure oxygen; would that fire hazard be worth the risk in space (especially after Apollo 1), or would they need to design a mechanism to temporarily mange it? I could see that argument having a significant impact on the cabin design.

But yeah. We can do better. A damn sight better. We can illuminate and record and monitor so much better. A couple years ago I stuck a 20 dollar pen camera in a machine and captured video - with sound - at such an unbelievably higher resolution and fidelity than what they had eked out at incredible cost; it's downright heartbreaking to think what they could have done today instead. Hell, we could probably now just simulate portions of the effects.

I'd hope the scale of this experiment would never need to be repeated today. We're likely at the point where we can risk learning from accidents now.

Addendum: Here's an interesting clip about a year later.

https://www.youtube.com/watch?v=KO8L9tKR4CY EDIT: `curtis beat me to it: https://news.ycombinator.com/item?id=10819055

I wouldn't pay too much heed to the commentary, since we can be sure the test pilot's survival wasn't miraculous at all - he was repressurized fast enough survival was very likely. But you can see how primitive it was, and how little was understood. That one accident was so useful, simply because the subject was concious for a few seconds and could talk about it.

I'm glad (at least hopeful) we're past that sort of groping in the dark.

EDIT: Whoops, Apollo 1 happened two years later. I remembered it had a full oxygen environment for - IIRC - keeping the astronauts more alert and safer at low pressures. I'd be interested to know if that was informed by the dog/chimp study, and if they only reversed their decision for a full oxygenated cabin after the crew burned alive. These days I just assume all safe industry/procedures came from someone's loss.

It's definitely a touchy subject and disturbing to the general populace, but such experiments are necessary for the advancement of the human race.

I for one am glad to know that dogs in a vacuum spontaneously deficate. I suspect there is a vacuum that develops overnight in the corner of my living room.

Yeah. Now you don't have to blame the dog! :)

See my reply above. I think these experiments were unnecessary.

These animal experiments were done because they were convenient, not because there wasn't an alternative.

Oooh, I realize, that 19th centure statement about this being 'necessary for the advancement of the human race' is just you trolling (or sarcasm?), and I fell for it. Doh!

It's interesting to think just where would we be if we could retroactively apply our current moral views on science to the past times. With microscopes, X-rays, MRIs and computer simulations we can do science without harming other creatures. But we couldn't do that even as recently as 100 years ago. Would we ever have medicine without thousand of years of animal testing?

Hell, we know what is edible and what is not because in the past few thousand years people accidentally killed themselves by eating crap.

This is exactly what bothers me about makeup companies (and the like) that advertise themselves as never having experimented on animals. While they may not be looking at MSDS sheets [1], they are looking at something that tells them which chemicals are safe. And, in doing so, they are relying on millenia of accumulated knowledge about toxic effects, paid for with a lot of human death and suffering and, possibly, someone else's animal experimentation.

[1] https://en.wikipedia.org/wiki/Safety_data_sheet

Why does that bother you? The wording doesn't seem misleading (as long as they are just using historical data, not incentivizing current production) and avoiding that knowledge would in fact bring more, not less harm to animals (if we include humans).

To me that sounds a very Augustinian view, in which we can never claim to be innocent of anything, because our life is shaped by past sins which we inherit. Personally, I reject that completely; we should acknowledge that actions by others in the past shape the present, but not feel ashamed of them.

That's a good question, one that would take me a while to explain, so I'll keep it short. I did not mean to imply anything about innocence or lack of it.

I guess I'm deeply bothered by proud statements of accomplishment that ignore profound and costly inheritance. PETA would never acknowledge that "cruelty-free" owes a debt to what they would term "cruelty". It's that lack of acknowledgement that bothers me.

I am a utilitarian. If you can make the argument that an experiment is a net good, then I can support it. The problem is I don't actually believe that this is the case for most experiments.

The smallpox vaccine was famously tested on a child. He was given the vaccine and then injected with smallpox. All based on a crazy theory. And the smallpox vaccine saved millions because of that test.

There are many similar examples from the early days of medicine. People just tested things when they needed to. The first anesthesia had only been tested on a dog, once, before being taken to the operating table.

Now hundreds of people die every year because we can't test things quickly enough. Human testing is expensive, there are a ton of conditions that make it impossible in many cases, there aren't enough subjects, we can't release drugs if there is even the tiniest doubt they might not be safe or effective, etc.

Many lives could be saved if we applied a little utilitarianism. But instead we only selectively apply the argument where it's convenient. The greater good argument is fine as long as it's just hundreds of chimps and dogs being tortured for basically no gain. But don't risk a single child if it could save millions! Or even a consenting adult in many cases.

Drug testing ultimately is an utilitarian tradeoff - on the one hand, testing too slow means people die; on the other, testing too fast increases the risk of releasing a drug that kills people. I feel we're too far on the "testing slow" side, but I honestly don't know enough to be sure.

As for human trials, situation gets complicated because incentives. I'm all for consenting adults being given experimental drugs, but there are so many avenues for abuse (and people are so good at using them) that I'm not surprised it's heavily restricted or banned altogether. Because today's consenting adult will be tomorrow's prisoner forced to do it, next month's poor schmuck tricked into it by marketing, and next year's every one of us.

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