The Human Body May Not Be Cut Out For Space 267
Hugh Pickens DOT Com writes "The human body did not evolve to live in space, and the longest any human has been off Earth is 437 days. Some problems, like the brittling of bone, may have been overcome already. Others have been identified — for example, astronauts have trouble eating and sleeping enough — and NASA is working to understand and solve them. But Kenneth Chang reports in the NY Times that there are some health problems that still elude doctors more than 50 years after the first spaceflight. The biggest hurdle remains radiation. Without the protective cocoon of Earth's magnetic field and atmosphere, astronauts receive substantially higher doses of radiation, heightening the chances that they will die of cancer. Another problem identified just five years ago is that the eyeballs of at least some astronauts became somewhat squashed. 'It is now a recognized occupational hazard of spaceflight,' says Dr. Barratt. 'We uncovered something that has been right under our noses forever.' NASA officials often talk about the 'unknown unknowns,' the unforeseen problems that catch them by surprise. The eye issue caught them by surprise, and they are happy it did not happen in the middle of a mission to Mars. Another problem is the lack of gravity jumbles the body's neurovestibular system (PDF) that tells people which way is up. When returning to the pull of gravity, astronauts can become dizzy, something that Mark Kelly took note of as he piloted the space shuttle to a landing. 'If you tilt your head a little left or right, it feels like you're going end over end.' Beyond the body, there is also the mind. The first six months of Scott Kelly's one-year mission are expected to be no different from his first trip to the space station. Dr. Gary E. Beven, a NASA psychiatrist, says he is interested in whether anything changes in the next six months. 'We're going to be looking for any significant changes in mood, in sleep, in irritability, in cognition.' In a Russian experiment in 2010 and 2011, six men agreed to be sealed up in a mock spaceship simulating a 17-month Mars mission. Four of the six developed disorders, and the crew became less active as the experiment progressed. 'I think that's just an example of what could potentially happen during a Mars mission, but with much greater consequence,' says Dr. Beven. 'Those subtle changes in group cohesion could cause major problems.'"
The solution may be simple (Score:5, Funny)
The solution may be much simpler than thought, Nasa only recruits High performing Individuals these people have a quite well documented need to perform and to be "busy" mentally or physically what they might need is couch potatoes or Mall security guards.
Re:The solution may be simple (Score:5, Funny)
Breed em' (Score:3)
Re:The solution may be simple (Score:5, Funny)
In other words, they should hire expendable people
It worked for the security team in Star Trek
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Hmm... didn't the rise of the TSA happen when some Star Trek installation was finally canceled? I smell a connection...
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Making the TSA into real-life red shirts just makes sense. In the Star Trek world, Redshirts were allegedly for security, but did little more than get themselves killed. They were Star Trek's version of security theater! The TSA is our version of security theater. So at least make them useful and blast them into space. They can even have some nice, new, shiny, red spacesuits to wear.
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If Iran gets around to putting a man into space soon, you might well see a TSA presence in earth orbit...
Who would of guessed! (Score:2)
Thanks Dr. Obvious!
Of course humans aren't adapted for space. (Score:5, Insightful)
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Off-earth colonies, whether lunar or Martian, would help the evolution of humans better suited for the stress of space.
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Sure thing. We'll gradually get rid of this pesky atmosphere of ours and slowly adapt to more space like conditions. Of course turning the gravity and magnetic field down will be a challenge onlu hollywood can meet.
Re:Of course apes aren't universal explorators. (Score:5, Insightful)
Incorrect. It is far more efficient to adapt your bodies to survive the environment.
Then why do people build houses? Why were things like the furnace and the air conditioner invented? Heck, why was clothing invented?
Most of Earth's surface is an unsustainable environment for humans, for at least part of the year. We only live on this planet because we have developed many ways of altering the environment.
The "437 days in space" is a lie - humans cannot survive at all in space. The 437 days was in a capsule, a local modification of the true environment of outer space.
Roll on! (Score:5, Insightful)
Re:Roll on! (Score:5, Informative)
Dealing the coriolis and tidal forces might be worse than the problem it's trying to solve, unless you have a really enormous centrifuge.
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Realistically, long journeys are going to require a really enormous "centrifuge" anyway. Ideally, the entire vehicle will rotate, except maybe the drive section.
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Re:Roll on! (Score:4, Interesting)
You'll need accelerometers mounted in various places, and some moveable counterweights along the spokes to adjust for changes in weight balance , preventing wobble.
Or you need the ship to be massive enough to where a few humans on one side of the ring don't amount to a hill of beans.
The next step to massive exploration of space is asteroid mining. We can't even build ships big enough.
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Wouldn't a few humans amount to a small hill of beans pretty well?
Only in this crazy world.
Solve for a simpler case (Score:4, Insightful)
An astronaut climbs in and presses a button and the system compensates, much like fuel redistribution on a modern plane. Once the system is balanced, it spins up. Astronaut sleeps under gravity. Wakes up. Gets out. Time for next astronaut to sleep. Repeat.
Re:Roll on! (Score:5, Interesting)
Dealing the coriolis and tidal forces might be worse than the problem it's trying to solve, unless you have a really enormous centrifuge.
Or two modules with a long tether [wordpress.com] spinning round their mutual centre of gravity
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I'm not sure a 'cable' is the right thing, but yes, that's the way to do it.
(Some sort of 'tube' that people can use to go from one side to the other is much more sensible)
Re:Roll on! (Score:5, Interesting)
I've been wondering why they don't at least do some animal studies on this centrifugal "gravity" idea. I mean how tough would it be to rig a rat cage and counterweight to rotate at some fraction of 1g? Put some critters in there for a few months, and take a control group along for the same duration, and see what happens. It probably wouldn't even cost very much, but could yield some key insights.
Re:Roll on! (Score:4, Interesting)
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It probably wouldn't even cost very much
Remember, we're talking NASA here.
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No-one wants to clean up the rat puke.
Re:Roll on! (Score:5, Informative)
Rats can't puke.
http://www.ratbehavior.org/vom... [ratbehavior.org]
Re:Roll on! (Score:4)
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NASA had such a mission on the cards pre-2010, but it was scrapped.
Re:Roll on! (Score:4, Interesting)
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Like a homicidal AI?
A tethered design more realistic in near term (Score:4, Informative)
Turning one's head rapidly in such an environment causes a "tilt" to be sensed as one's inner ears move at different rotational rates. Centrifuge studies show that people get motion-sick in habitats with a rotational radius of less than 100 metres, or with a rotation rate above 3 rotations per minute. However, the same studies and statistical inference indicate that almost all people should be able to live comfortably in habitats with a rotational radius larger than 500 meters and below 1 RPM.
That would mean a rather massive structure. So, an alternative design that would use less material is two stations tethered together and rotating around a common center. Or a station and a counterweight. Still, this requires a strong tether, which also means additional mass.
This approach is suggested, for example, in this Mars Society article: The Use of SpaceX Hardware to Accomplish Near-Term Human Mars Mission [marssociety.org].
For radiation shielding, they suggest to use the "consumables", which probably means fuel, raw materials, equipment and water.
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So, an alternative design that would use less material is two stations tethered together and rotating around a common center.
The best solution, I'd say. Simple and elegant.
Re:A tethered design more realistic in near term (Score:5, Interesting)
You'd still need some sort of centrifuge, to stave off all the muscular and skeletal side effects of zero G; but tampering with the inner ear to prevent the subject noticing the various imperfections associated with a fairly small centrifuge might well become doable with small computerized implants in the relatively near future...
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Well, at least we have verified empirically that the "big spinning sphere shaped vehicle" works.
Re:Roll on! -even simpler : a rope ;-) (Score:2)
On the very earliest Apollo missions, experiments were done with a rather basic rope linking the reentry capsule and the LEM, or the supporting module section, I don't remember. The whole was spun *manually* and with analog devices of course.
It should be simple to plan such a move even with small interplanetary devices, rather than starting with ambitious internal spinwheels.
The only issue in such a case is maintaining a location where an Earth-facing antenna wouldn't move, but rotating around the Earth dir
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A big spinning wheel shaped vehicle should suffice
Naw, just install gravity plates.
http://en.memory-alpha.org/wiki/Gravity_plate [memory-alpha.org]
Doesn't help with the radiation, though.
Re:Roll on! (Score:5, Funny)
Do you want fiords with that order ?
Talk to Slartibardfast on Magrathea
For a more moble solution, try the Fleet Of Worlds made by the Puppeteers
wow (Score:5, Funny)
Millions of years of evolution in an environment with gravity has really screwed up our plans for galactic supremacy.
Re:wow (Score:4, Insightful)
Not to mention the universe's stupid speed limit!
Obvious. (Score:2)
If got had meant us to be in space he would have made us with skin that replaces cells with polarized silicone and given us acid for blood.
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If got had meant us to be in space he would have made us with skin that replaces cells with polarized silicone and given us acid for blood.
You are just looking for a viable excuse for shooting your mother in law to the moon.
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You are just looking for a viable excuse for shooting your mother in law to the moon.
My mother in law is larger than the moon, you insensitive clod.
That's some bad eyeball squashing (Score:5, Funny)
Another problem identified just five years ago is that the eyeballs of at least some astronauts became somewhat squashed. ... 'We uncovered something that has been right under our noses forever.'
I'm not a doctor, but if your eyeballs have always been under your nose then I suspect you have a pre-existing condition. Don't blame space.
To be fair, in zero gravity, it's easy to get confused about 'under' and 'over'.
Re:That's some bad eyeball squashing (Score:4, Informative)
To be fair, in zero gravity, it's easy to get confused about 'under' and 'over'.
that's why I usually bet on the spread
Under our noses? (Score:2)
That's pretty damned squashed, our eyeballs are normally above the nose.
50 years (Score:2)
Regarding the radiation issue. How about we create a magnetic field ourselves? Energy requirements may be too high, I don't know. Just an idea...
The human body did not evolve to live on ships (Score:5, Funny)
"The human body did not evolve to live on ships, and the longest any human has been off Land is 437 days. Some problems, like scurvy, may have been overcome already. Others have been identified -- for example, sailors have trouble eating and sleeping enough -- and people are working to understand and solve them. But Kenneth Chang reports in the NY Times that there are some health problems that still elude doctors more than 5000 years after the first sea voyage. The biggest hurdle remains sea water. Without the protective cocoon of the ships hull and atmosphere, sailors receive substantially lower doses of oxygen, heightening the chances that they will die of suffocation. Another problem identified just five years ago is that the eyeballs of at least some sailors became somewhat squashed when hit by a boom. 'It is now a recognized occupational hazard of sailing,' says Dr. Barratt. 'We uncovered something that has been right under our noses forever.' Officials often talk about the 'unknown unknowns,' the unforeseen problems that catch them by surprise. The eye issue caught them by surprise, and they are happy it did not happen in the middle of a mission to Madagascar. Another problem is the lack of stability jumbles the body's neurovestibular system (PDF) that tells people which way is up. When returning to land, sailors can become dizzy, something that Mark Kelly took note of as he piloted the sailboat to a landing. 'If you tilt your head a little left or right, it feels like you're going end over end.' Beyond the body, there is also the mind. The first six months of Scott Kelly's one-year mission are expected to be no different from his first trip to the open sea. Dr. Gary E. Beven, a NASA psychiatrist, says he is interested in whether anything changes in the next six months. 'We're going to be looking for any significant changes in mood, in sleep, in irritability, in cognition.' In a Russian experiment in 2010 and 2011, six men agreed to be sealed up in a mock submarine simulating a 17-month mission. Four of the six developed disorders, and the crew became less active as the experiment progressed. 'I think that's just an example of what could potentially happen during a submarine mission, but with much greater consequence,' says Dr. Beven. 'Those subtle changes in group cohesion could cause major problems.'"
Re:The human body did not evolve to live on ships (Score:5, Insightful)
Better summary:
There are problems with what we're trying to do. Some of them surprising. There are also probably solutions that we haven't figured out yet.
squashed eyeballs (Score:5, Interesting)
I have no trouble believing the human eye does not do well in zero gravity. Case in point, I have a bookstand that holds a book upside down, to read lying down in bed. If I read for an hour in that position, my vision becomes all blurred, something that doesn't happen when I read with my head upright or tilted backward at a slight angle.
I'm pretty sure proper vision depends on gravity pulling the eyeball the direction the eyeball is used to to maintain its shape, i.e. down.
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Or maybe just *not* having gravity drag your eyeball the wrong way?
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http://en.wikipedia.org/wiki/P... [wikipedia.org]
The brain is intimately involved with how we perceive things. A bunch of experiments have been done, for example (recounted in the link above), one guy wore glasses that inverted everything -- he saw everything "upside down." After a few days, his brain flipped everything the right way!
I can imagine that years with low or no gravity would do far more than just affect the physiology. This isn't just a mechanical phenomenon. It's not just a matter of distorted eyeballs or inne
Genetic Engineering? (Score:2)
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See: Homo Celestis from "Man after Man" by Dougal Dixon
Obligatory Move Reference (Score:2)
Right under our noses (Score:2)
Another problem identified just five years ago is that the eyeballs of at least some astronauts became somewhat squashed. 'It is now a recognized occupational hazard of spaceflight,' says Dr. Barratt. 'We uncovered something that has been right under our noses forever.'
Was it uncovered while upside down?
Another idea (Score:2)
The biggest hurdle remains radiation. Without the protective cocoon of Earth's magnetic field and atmosphere, astronauts receive substantially higher doses of radiation, heightening the chances that they will die of cancer.
Why not make the earth itself our spaceship? Once we find another inhabitable planet, dump half the population and continue our quest for space colonization (only now with 2 spaceships).
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"Why not make the earth itself our spaceship?"
Essentially it already is. The whole solar system is moving through the galaxy at around 100 miles per second.
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Re:Another idea (Score:5, Funny)
Earth is already a spaceship. The problem is, we have no control over where it's going.
But we found the climate controls! We just argue over how hot to set them.
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It's the driving controls we're looking for. On Mars it's on the face, and on Mercury it's on the butt.
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Are you suggesting somehow attaching rocket boosters to the Earth and sending the entire planet flying through space to find another world? If so, there are many problems with that plan. First of all, building rockets that big to move the Earth (but not shatter it to bits) would be a huge undertaking. Powering it would be another huge problem. However, let's assume we're built the boosters and figured out how to power them. We somehow overcome our orbit and blast the Earth out of our solar system. Her
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I know this is a joke, but for reference the energy required to accelerate the Earth to escape velocity is ten billion times its gravitational binding energy. Unless you give it a really, really gentle push you'll vapourise it before you get it out of the solar system.
First sentence sums it all up (Score:2)
"The human body did not evolve to live in space,..."
Why would we expect it to function normally, there?
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The human body evolved in Africa.
Why do we expect it to function normally, say, in North America?
Why do we even expect the laws of physics to be the same in two different places?
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The human body evolved in Africa.
Why do we expect it to function normally, say, in North America?
Why do we even expect the laws of physics to be the same in two different places?
Because for all practical purpose, Africa and North America are equivalent.
As for the laws of physics, I was always taught that they are the same everywhere, even in space.
Unsolvable ones? (Score:2)
Radiation should be top of the list, unless we develop a somewhat thin metamaterial or something like that that reflects or absorb radiation (in the worst case we could rely on poop [pcmag.com], but may exist other options) anything that implies long time on space (like a trip to mars, or trying to have self-sustained colonies in space). But if this one can't be solved, that should put an end to especulations about aliens visiting us or we visiting other star systems, ever, same for colonize anywhere else in this solar
The Human Body May Not be Cut Out For The Ocean (Score:4, Informative)
PersonFrom1420 submitted via church door nail, "The human body was not designed by God Almighty to live on the ocean in seafaring ships, and the longest any human has traveled has been close to coastlines. Without the protective cocoon of the coastal fish and shore leave, nautical travelers are subjected to Gout, Scurvy, and a malaise of the spirit that shall certainly result in dire consequence for any vessel attempting to find a new world to explore. In a Royal experiment, debtor's prisons are filled with scum of the streets, sealed away, and their outcome is surely the same as a nautical traveler who looks forward to a new life and possible riches from fruitful exploration. Also, if even one ship has a mutiny, NASA (the Nautical Authority of the Spanish Armada) should instantly force all manned sea faring traffic to halt for over a year, as various Royal Agencies, none of whom understand how to tie a knot, let alone sail a ship, confer over the loss, and consider halting this foolishness to focus on more incense swinging for the plague and merkin production at home. Certainly there is no profit to be gained in these new lands that are worth losing entire ships of human beings over, and there can be no future lands there that will ever be suitable for our children's children. May this missive find you in good health, Signed P.F.1420"
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You appreciate that "not cut out for space" is just an attention-grabbing headline, and both summary and article are about how NASA are super psyched to be investigating and attempting to solve these problems?
KISS (Score:3, Insightful)
Use the KISS (Keep It Simple Stupid) principle - don't send people. Never send a person to do a robot's job.
I hate to say this, because I grew up with the excitement of the Apollo program (you may have heard of it in your ancient history classes), but robots, or whatever you want to call unmanned probes or satellites, have done almost all of the scientific and practical work in space, and for a fraction of the cost of manned stuff. It's hard to think of a justification for manned space travel other than the Buck Rogers publicity or the science fiction notions of humanity surviving on another planet after some catastrophic event on earth. The former is silly - that's why we have sci-fi. As for the latter, anyplace on earth, including the South Pole or deep mine shafts, is a much more benign environment than space. We, or at least a few of us, could survive something like a nuclear war or the event that killed the dinosaurs, much more easily on Earth than on the moon or Mars. We have to prevent a mine shaft gap! (and the prodigious service part doesn't sound so bad either).
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This is bad analogy. Space exploration has benefited the basic science, so its certainly important. Sending robots to Moon and Mars can also help to answer tons of questions. The issue is not about ending space exploration. It's about using robots instead of humans.
Human body is also not cut out for a lot of things (Score:3, Insightful)
Agreed, 100%, the human body is not cut out for space. Certainly, like all life on earth, we require oxygen, we evolved with gravity, radiation is toxic, and so forth. Our bladders, for instance, tell us that we need to urinate based on a sense that depends on gravity holding urine down at the bottom; without gravity, if we wait until we feel the need to urinate, we need to be catheterised.
BUT... the human body isn't cut out for a lot of things THAT HUMANS DO ON A DAILY BASIS. We're not cut out for flight; we're not cut out for deep water diving; we're not cut out for rapid movement on ground. Yet, with technology, we do all of the above. Absolutely, space flight requires far more in the way of adaptations to protect our (very) frail bodies than air travel, SCUBA, or cars. But human history, broadly simplified, is the story of us using our brains to overcome our manifest physical handicaps.
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The issue is that you can't live in a car or live underwater for months or years. Likewise, almost anyone probably could spend a few hours on a space station without much ill effects. The issue with spending a very long time on the space station.
It's time to fork the human species (Score:3)
isolation isn't new (Score:2, Insightful)
Explorers used to set off in a small group and be trapped for months on end (e.g. ships frozen into the ice) and not freak out. Perhaps Russian and NASA test subjects are being chosen from the wrong population for long duration missions. Certainly, NASA selects for the "test pilot, can-do" sort of person. As Tom Wolfe describes it "I tried A, now I'm doing B, and if that doesn't work, I'm going to do C". These folks are action oriented, and want to always be doing things (and NASA doesn't help.. they sc
Why no fake gravity? (Score:2)
SciFi visions of space travel almost always include gravity. And it's not like it's hard to do: Build round space station, spin it.
I assume there's a good reason why we don't make use of the principle to provide astronauts with some semblance of gravity. What is it?
Artificial magnetic field (Score:2)
Clifford Simak predicted this (Score:4, Interesting)
Re:Space or Lack of Gravity? (Score:5, Interesting)
That is a good idea in theory, but artificial gravity by rotation has a rather big problem involved: We're not 1 inch tall. Gravity by rotation is dependent on velocity. And depending on how "big" that wheel is, that velocity may be considerably different at the floor and 6 feet up.
In other words, if that wheel is too small and you spin it too fast (to get to that 1g you want), you'd be nauseated to the extreme.
I don't have the exact numbers in my head right now, but I do distinctly remember that the required size was somewhere in the vicinity of "friggin' huge" to avoid such a fate.
Spin (Score:4, Insightful)
Long term residence at zero G may be a problem, but we may not need full gravity (9.8m/s2) to be healthy, especially if you don't have to return to earth.
Lets face it, the first planets we colonise have a reduced gravity ( Mars 3.7m/s2 and Luna only 1.6m/s2)
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One of the astronauts in the story likened being in space to hanging upside-down for a couple of minutes.
Keep in mind only a handful of people have even experienced it. Some will be better- or worse-suited for the environment.
The radiation exposure is a much bigger hurdle. Humans will adapt. Babies will be born off-World one day.
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There once was a babe born in space
The first of the whole human race
But the kid's DNA
Looked like bad macrame
Cos nobody shielded that place
Re:Space or Lack of Gravity? (Score:5, Informative)
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You don't need to make a wheel.
Just hook up two stations using a tether of any length, then rotate.
(Like Katatsumuri already mentioned above).
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Doesn't have to be a big wheel, just use a counterweight (such as a spent upper-stage) at the end of a long tether. I'm too lazy to do the calculations, but even just a few hundred meters ought to be plenty to provide a significant fraction of 1g with a rotation time longer than 30s, at which point the motion would be practically imperceptible.
Of course, a few hundred meters of cable would weigh a couple of tons at least, but for a spacecraft that weighs 20 times that much, it could still be a worthwhile tr
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Of course, a few hundred meters of cable would weigh a couple of tons at least, but for a spacecraft that weighs 20 times that much, it could still be a worthwhile tradeoff.
Not if it's made of nanotubes.
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What makes you think we want 1g? Perhaps Mars gravity would be sufficient. Or even Lunar gravity. Till we make the experiments, we won't know.
As to minimum size, if we allow for 5% difference in speed between head and feet, we'd need a 40m radius wheel. Or just a 40m long boom with a pod at one end, plus a short boom with a counterweight at the other end (or a really long
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That would need far too much fuel to ever be practical.
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Re:Space or Lack of Gravity? (Score:4, Interesting)
According to someone else's comment just above, the absolute minimum size required for most humans to be comfortable is 100m radius and rotation rate of 3 rpm. Going up to 500m radius and 1rpm would make the habitat comfortable for almost everyone.
Sounds like a lot, but we build much larger structures that this all the time here on Earth which are capable of withstanding the forces of storms at sea, battering waves, etc.; they're called "ships". The biggest ones are about 400m long. Something built for space doesn't need to be remotely as rugged as an aircraft carrier, since there's no gravity or other forces to deal with besides those caused by rotation and propulsion, so it really shouldn't be that hard to build something that size if we put our minds to it and actually dedicated serious resources to the task instead of sitting around and debating Creationism.
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In other words, if that wheel is too small and you spin it too fast (to get to that 1g you want), you'd be nauseated to the extreme.
Would you stay nauseated though or would you get used to it?
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No, Mars is about 1/3g.
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1) You don't know what FUD means if you think documented and poorly understood medical issues are FUD.
2) NASA already knows about that technology. NASA invented or is actively involved in much of it. However as they are scientists and engineers, they actually have to build and test things and evaluate their assumptions, rather than just throwing out a hypothetical solution and being smug.
You, sir, are the myopic one here.
Re:Why does nasa never consider submariners? (Score:4, Insightful)
Er... they do.
Notice that most of the problems are associated with the lack of gravity (not generally a problem on a submarine), not a confined environment.
You don't get bone loss as a submariner.
You don't get modified eyeball shapes as a submariner.
You don't get extreme dizziness once you set foot on dry land as a submariner (an experienced one at least)
Sleep loss? Maybe. But saying you can't sleep on a tin box inside an ocean of resonant water where you have to keep absolutely silent is a bit different to a tin box travelling at thousand of miles per hour in the vacuum of space.
In fact, if anything, it's completely the OPPOSITE problem.
Hence why people at NASA don't see these problems coming.
I'm just thankful it's not something more serious and obviously debilitating (if you're going to spend your life in space, bone weakness isn't going to be much of an issue - it's only the return to Earth that's the problem) or the whole "let's life in space" program might have been dead before it began.
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Crew sizes, in terms of the social dynamic and the degree of specialisation/generalisation required.
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Crew sizes, in terms of the social dynamic
We no longer have crews as small as aircraft crews. Moreover, flights are short, where submarines go out to see for months - more the time scale of current space missions.
degree of specialisation/generalisation required
Most submariners have highly specialized positions on the sub, but are also cross-trained to do another job if necessary. Moreover they're all trained to do important safety tasks like fighting leaks and fires, and for escape procedures.
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Everyone can spend a few hours in a car or a space station, but you can't stay in a moving car for days. The issue is with staying on a space station for months or years.
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That's for making me come to Mars!
[Kicks his groin]
You know how much I hate this fucking planet!