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Trip To Mars Could Damage Astronauts' Brains
Hugh Pickens writes writes "Alex Knapp reports that research by a team at the Rochester Medical Center suggests that exposure to the radiation of outer space could accelerate the onset of Alzheimer's disease in astronauts. 'Galactic cosmic radiation poses a significant threat to future astronauts... Exposure to ... equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer's disease' says M. Kerry O'Banio. Researchers exposed mice with known timeframes for developing Alzheimer's to the type of low-level radiation that astronauts would be exposed to over time on a long space journey. The mice were then put through tests that measured their memory and cognitive ability and the mice exposed to radiation showed significant cognitive impairment. It's not going to be an easy problem to solve, either. The radiation the researchers used in their testing is composed of highly charged iron particles, which are relatively common in space. 'Because iron particles pack a bigger wallop it is extremely difficult from an engineering perspective to effectively shield against them,' says O'Banion. 'One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.'"
Once you leave the atmosphere of this blue planet, *everything* will kill you. No amount of engineering, terraforming, or any other science fiction magic will ever make any other body within human reach survivable for long, and certainly not without HEAVY and CONSTANT support from earth.
There is no earthly analogy. Even the most hostile environments on earth usually have at least SOME oxygen, water, soil, air pressure--*something* that could make it at least *somewhat* survivable. Leave earth, and finding even *one* of these conditions becomes very rare. Establishing even the smallest of colonies out there will take orders of magnitude more resources than it will take to solve even the worst problems here. Short of a planet-obliterating collision, we'll always have a better shot on earth. And even with such a collision, having a colony will only slightly delay the inevitable, since no colony out there could survive for long without constant support from earth.
No other body is survivable in our solar system. And with the next-closest solar system at over 100,000 years journey away in the fastest craft we can build, don't think of escaping to another solar system either.
We are stuck here. There is no escape. Dream all you want--write stories about it, make movies about it. But we ain't leaving.
What political party do you join when you don't like Bible-thumpers *or* hippies?
A trip to mars is probably "one way" so who's worried about Alzheimer's...?
No sig today...
The sudden stop on impact will cause the most damage. It's not the fall, but the sudden stop that kills you.
Wrapping the ship in water frozen or not, is a far more practical protection measure than wrapping it in lead.
You can do a lot more with water once you get there.
tin foil hats... duh...
a 6' shield of concrete? Why not hollow out asteroids that are near our orbit, and adjust their orbit to transit between earth and mars?
No amount of engineering, terraforming, or any other science fiction magic will ever make any other body within human reach survivable for long
Space is far more hostile than any planet, and we can manage to survive up there for quite a long time.
Terraforming is not "magic", and small scale examples of humans changing conditions where they live abound.
Even the most hostile environments on earth usually have at least SOME oxygen, water, soil, air pressure
The moon even has most of those.
Mars has all of them.
no colony out there could survive for long without constant support from earth.
They will not if you never try.
We are stuck here. There is no escape.
You might be, but all the trapping being done is by your own mind, not any kind of scientific basis.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Is a strong magnetic field not an effective solution for the solar wind? Heck, with large enough solar arrays, you could use the solar wind to power a magnetic field that would protect the crew cabin from the solar wind. There's something poetic in that. Alternately, if fusion ever gets off the ground as a power and thrust source, you could just use its magnetic field to protect the crew.
!#@%*)anks for hanging up the phone, dear.
Colonization of other worlds is ultimately about survival of the human species. Earth only has another 1 billion years or so of habitability, presuming we don't get hit by a Tunguska-sized asteroid between now and then.
We have the choice of traveling to the planets (and eventually the stars) or becoming extinct. And we're the first species in Earth's 4½ billion years to recognize that we have this choice and that there's simply no better time to act on it.
!#@%*)anks for hanging up the phone, dear.
If magnetic fields protect the earth, we can't the same be done to a space craft?
-- By all means let's be open-minded, but not so open-minded that our brains drop out.
I don't understand why they would have to wrap the whole ship in a 6-foot thick lead shield. That's incredibly inefficient. Just make 6-foot thick lead helmets instead. It's a lot cheaper and their brains will still be protected from the killer brain rays.
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
Me: "Here's a pen dad, sign the picture for them" ...
Dad: "Why do they want my signature?"
Me: "You were an astronaut when you were younger, you went to the moon"
Dad: "What?"
Me: "Yes, you went to the moon."
Dad: "We've been to the moon? That is amazing!!!"
Me: "Yes Dad, and *you* have been to the moon"
Dad: "*I've* been to the moon?!?"
Me: "Absolutely, see that picture you are signing? That is you"
Dad: "OK. Why am I signing this?"
Me: "Your were an astronaut when you were younger, you went to the moon"
"Oh, you hate your job? There's a support group for that, it's called everyone, they meet at the bar."
Its all about exposure time. The longest Apollo mission lasted about two weeks. Mars missions will last many months, possibly a year or more.
Have gnu, will travel.
A trip to mars is probably "one way" so who's worried about Alzheimer's...?
And the best part is once there you wont even remember why you'd want to leave anyway!
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Trip to the moon, 3 days, trip to mars 3 months in the best possible scenario. If the moon landing was a scam, the USSR would have absolutely 100% for sure called us out on it.
Good-bye
People like you were also prognosticating that we were all going to starve, that the environment would be destroyed by pollution, that we'd run out of oil, that we'd freeze to death, that we'd boil to death... it ain't happening.
The solar system is a tremendously rich place, full of water, hydrocarbons, and metals, in convenient large chunks that are easy to exploit and easy to move around. They provide everything we need in a form that is far simpler to use than anything on earth. Food and oxygen production are trivial in space: there's plenty of sun, space, water, and carbon. Add some algae, and you get all the oxygen and food you would ever need.
As soon as we capture and exploit the first chunks of iron, carbon, and water in space, there will be an explosion of innovation and movement into the solar system; it will make the changes of the last century look like child's play. Within a few decades, engineering in space will dwarf the entire infrastructure we have built on earth. And we need no new technology for any of that.
The way I see it, it couldn't damage their brains. It would also have the advantage of getting them off Earth.
âoeAny society that would give up a little liberty to gain a little security will deserve neither and lose both.
From the paper, you noticed that they irradiated the mice very quickly.
"using a foam tube holder positioned at the center of a 20×20 cm beam of iron ions accelerated to 1 GeV/ at a dose rate ranging from 0.1–1 Gy/min. Male mice received total doses of either 10 cGy or 100 cGy. Female mice received only a 100 cGy dose."
1Gy/min is a lot dose in a very short period. So for the female they gave all the dose in a timeframe measured in mins. At lower dose rates, cells repair the DNA damage better. I think that lower dose rates would be more likely to occur in a mars trip.
For those without much radiation background, 100cGy delivered in 1 min isn't the same as 100cGy delivered over 6 months.
The moon is still slightly protected by earths magnetic field. The field doesn't just suddenly end; inverse square law, and all that.
Actually, the moon is usually not protected by the earth's magnetic field. The earth's magnetic field is greatly affected by solar wind so that the part of the field projecting towards the sun is squished and the part away from the sun forms a long "tail"
If you look at this website, you can see that the moon only spends about 6 days/month inside the earth's magnetic tail.
Not only that, extremely dilute atmospheric particles have been discovered on the far side of the moon - the moon is technically inside Earth's atmosphere.
I think this is just false. Although some missions have detected traces of an atmosphere on parts of the moon (e.g., Apollo detected Argon, O2, CO2, CH4, etc, and LRO detected H3), these are thought to be from outgassing or sputtering from material inside the moon itself. The reason that some of them are similar to earth atmopheric components are that the earth-moon system may have actually been formed from prehistoric collision
No air, no water, no food, no sleep, no freezing, no unusual housing, no doctors, no psychologists, no morticians...
Robots win.
I was with you right up to "no doctors, no psychologists, no morticians". I have a machine intelligence project that watches me via Kinect and spiders the web from sites I visit, and recommends me links to things it thinks I'll like by continuously observing my activity cycles, common words of interest, and ratings of its past recommendations. For maintenance I would shut the system down by sitting at a dedicated console for the server cluster and logging into the command terminal. Imagine what that must be like to this neural network: It has a relatively consistently changing observation of cyberspace and my office, however when I sit at that terminal more often than not the world instantly changes by vast degrees - The lighting changes, perhaps even the clothes of the man on the chair changes abruptly there's suddenly much more new information online to analyze, and recommendations are thereafter poorly rated. The frequency of its recommendation notifications increases due to the influx of new and different data, but the timing is frequently off my schedule then, so my ratings of its suggestions are poorer than normal for a time. The architecture is a hive of neural networks that decide by consensus and compete for breeding rights based on my rating selection pressure... Some n.nets in the hive will "die" for their poor suggestions.
Last year I noticed that when I would sit at the chair in front of the MI's terminal new suggestions would begin popping up on my work terminal across the room (where they normally do), I would check them and rate them before shutting down the system, sometimes I would be distracted for quite some time by an interesting thing. It was an eerily life like behavior -- The increased suggestions prior to shutdown an indication of some primitive form of anticipation or perhaps even fear. I could imagine a child acting the same way in the MI's place, "Don't sit in the scary hate-chair! I promise I'll be good and give you links to sites you like." Of course I knew that there were merely genetic advantages to getting in good recommendations before the world-shifting shutdown, but it doesn't change the fact of the situation at all. "Irrational Fear" is just a term for some neural processes in humans that we don't yet understand. I have a precise explanation for the MI's behavior, but I wouldn't be wrong in classifying it under the nebulous term "fear". I've since started using a remote terminal session to initiate shutdowns, to disassociate my presence at that desk with the traumatic event.
I put it to you the sentient machine intelligence will have neuroses just like humans do. Any sufficiently complex interaction is indistinguishable from sentience, since that's what sentience is. Humans aren't special, neither is their behaviors. Why, even empathy is found in rats. We can look to ourselves to know what the sentient machine races will be like. They'll need doctors to heal their wounds, even if the terminology is changed to "mechanics" for repairing "malfunctions". They'll still need counselors and psychologists even if we call them "M.I. specialists". They'll still need morticians and cemeteries even if the terminology is "Part Recyclers" and "Junk Yards".
You say "no food", what is air and water to us than food? What is energy to robots but food? You say no sleep but indeed it's harder to see by night so the robots will take more advantage of the free light energy to be more active by day, as mars rovers currently do now. Of all the things you've said it's only "no unusual housing" that I find myself agreeing with. Even accounting for the possibility of much larger brains the primary difference will still be that the machines have sturdier bodies than humans.
The biggest problem with non sentient robots is that the neural lag between the sentient brains and these remote exten
"Yes, but radiation dose is a cumulative dose. The effect may not be exactly the same as receiving it all at once in a microburst, but the chance for DNA mutation is probably statistically close to being the same."
You get the same damages, but you also have DNA repair mechanisms and other cellular repair mechanisms that can handle a certain amount of trouble. Yes, you might get unlucky and get a mutation that makes that cell go immediately cancerous (Think of it as a golden BB). But, what happens more often is the damage builds up faster in large numbers of cells than it can be repaired and causes a cascade of problems.
A fast dose acts differently than a cumulative one over time. (That's not saying either is good. They're just different.)
Also, there are a number of effects that could be happening. Alzheimers only becomes symptomatic after a fair bit of damage. You have a neuronal reserve capability that can deal with some damage and still keep working fine. This is why drinking alcohol doesn't immediately cause neurological deficits. Though some cells are killed, the brain is redundant and other cells can pick up the slack as it were. After many years of heavy drinking, enough damage has been done that problems start to show up.
Almost anything that depletes neuronal reserve would be expected to accelerate alzheimers as it thus takes less damage from alzheimers itself to become symptomatic. This is why things like mild brain injury or chronic alcoholism would be expected increase the risk of alzheimers. (That's definitely seen for mild brain injury. Alcoholic dementia is similar to alzheimers in some ways and is thus hard to separate and get good cause and effect data so it can only be said to "probably" increase thge risk.)
The mice are already prone to alzheimers, so they have a major head start and may well react far more to something that kille some brain cells.
This study is an indication that there may be trouble of this kind. Further work is needed to determine whether this is likely to happen in significant amounts to human astronauts exposed at lower rates over longer times.
There are nearly 10,000 known Near Earth Objects (NEOs), and another 10,000 Near Mars Objects (NMOs) are expected (2 of which are known to orbit Mars). We have not found as many NMOs yet because they are farther away, but there is every reason to expect them to exist, and likely even more since they are closer to the source in the Main Belt.
No matter what orbit you choose, there will be some of these objects in nearby orbits. So I propose setting up "Transfer Habitats" in convenient orbits to get to and from Mars. You would start with some pressurized modules brought from Earth, then bring in asteroid rocks from nearby. This has numerous advantages:
* Solves the radiation problem, if you wrap a layer of rock shielding around your modules.
* Solves the boredom problem for the crew. They have more living space, and can spend their time growing food and extracting fuel from the rock.
* Reduces mass from Earth, because of the previously mentioned food and fuel you make yourself
* Eventually you can produce pure metals, glass, and other products to expand the habitat, and later ship to the next location (Phobos) where you repeat the process. Once the first of these shielded habitats is set up - in Earth orbit, the rest of them can come naturally over time.
* Producing fuel in Earth Orbit and at Phobos makes it easier to land on the Moon and Mars. It totally changes the economics from "hauling lots of fuel with expensive rockets from Earth" to "making fuel and other supplies wherever I am".
All of this is laid out in more detail in the book I'm working on (Section 4.12 in particular):
http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods
Dani Eder
(ex Boeing, now independent designer of self-supporting communities)
Okay, drinking it is out. But one of the advantages of water over other options is that you can dump it relatively easily if you need to lighten the load for an emergency, such as in the case of a fuel leak or the need to rush home (via less weight). Yes, you risk bodily damage from exposure if you yank the cord, but at least you get home.
Water may also be easier to incrementally fill up in orbit, since launching such a bulky ship in one shot is probably out.
Then again, a similar argument could be made for packing the sides with extra fuel, perhaps in a non-volatile form, such as the catalyst separated from the reactant. I imagine a combination of substances could be used to hedge the risk: water, fuel, food, spare parts, duct tape, etc. If you are going to have to bulk up, then bulk up on stuff that may serve different kinds of emergency needs.
Apollo 13 taught us you have to be flexible during unanticipated emergencies.
Table-ized A.I.
"Radiation shielding is hard, its not impossible."
Good points. Freeman Dyson says much the same, and does some calculations showing that in one of his essays, where he says, adjusted for inflation, the costs to go from Europe to the Americas was on the order of what it would cost now to go into space. Remember, many people coming over to the "colonies" came as indentured servants who had to work off their travel for seven years. So, as a ballpark figure, let's guesstimate that person was giving up US$100K per year for inflation-adjusted wages (people typically worked six days a week and fourteen hours a day back then), and that's US$700,000 as an indenture. So, the move to North America was not that cheap for many.
On radiation shielding, see Marshall Savage's "The Millennial Project" where he suggests simply having two layers of transparent plastic with six feet of water between them. We could get the water in space from asteroids or comets (or launch the water from the earth or the moon via mass driver). Radiation problem solved.
http://en.wikipedia.org/wiki/The_Millennial_Project:_Colonizing_the_Galaxy_in_Eight_Easy_Steps
http://tmp2.wikia.com/wiki/Main_Page
Other ideas from the Carter Administration:
http://www.islandone.org/MMSG/aasm/
Read James P. Hogan's "Voyage from Yesteryear" and "The Two Faces of Tomorrow" for some realistic hard sci-fi set in habitats.
http://www.jamesphogan.com/books/info.php?titleID=29&cmd=summary
http://www.baenebooks.com/chapters/0671878484/0671878484.htm
More ideas:
http://www.openvirgle.net/
All that said though, I would point out that the same sorts of technologies we need to live in space (such as near 100% recycling, healthier materials to be around, improved agriculture, portable doctoring and a better understanding of human nutrition and health, flexible manufacturing, improved governing processes for small communities, accessible digital libraries, improved conflict resolution skills, and so on), are mostly the *same* things we need to make Spaceship Earth work for everybody. So, overall, there is no deep conflict between an interest in space habitats and trying to make the Earth a better place.
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
Solved long ago. Spherical hab unit, shell of H2O outside the hab portion, just as thick as it needs to be. That shell is drinking water, fish habitat, exercise area, possibly even propulsion mass.
I've fallen off your lawn, and I can't get up.