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Mars Science

Trip To Mars Could Damage Astronauts' Brains 505

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.'"
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Trip To Mars Could Damage Astronauts' Brains

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  • 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 e

    • by I Read Good ( 2348294 ) on Wednesday January 02, 2013 @01:06PM (#42451303)

      Yeah, you're right. We should just give up.

      • Re: (Score:2, Insightful)

        I suppose you also regret giving up alchemy. Finding a cheap way to convert lead to gold is probably easier than flying to another star. Don't think of it as "giving up". Rather think of it as postponing until somebody happens to stumble on some breakthrough scientific discoveries.
        • by KingSkippus ( 799657 ) on Wednesday January 02, 2013 @03:07PM (#42452805) Homepage Journal

          Seriously? "Stumble upon" science? Man, I'm glad you had no authority in the Apollo program.

          The idea is that you don't wait for these technologies to serendipitously come along, you go research and find them. Maybe your success will be limited, but in the process, you will probably stumble upon things that will be useful in other fields. In this day and age when we're approaching ecological disasters and energy crises, I think that a lot of the technology researched in working on a manned mission to Mars would be very useful in other fields.

        • I suppose you also regret giving up alchemy.

          We didn't "give it up"; alchemy continuously transitioned into modern chemistry.

          Don't think of it as "giving up".

          I think NASA should "give up" on human space flight altogether... and leave it to the private sector. NASA should focus on exploration with space probes, fund basic research, and make the resulting data publicly and freely available. The rest will take care of itself.

    • Re: (Score:3, Insightful)

      by geekoid ( 135745 )

      By definition terraforming will do exactly that.

      " 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."
      no it wont, and , of course being able to do that means you need the tech that would also solve a lot of problems here

      "There is no escape. "

      I look forward to reading you published paper that ties all physics together and definitive proves chemical fuels are the only way we will ever be able to travel.

      What'

      • Of course, as soon as we have a working antimatter drive, the poster may revise the stated opinion. Until then, it is perfectly reasonable.
    • The Trap, Yourself (Score:5, Insightful)

      by SuperKendall ( 25149 ) on Wednesday January 02, 2013 @01:12PM (#42451385)

      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.

      • by ByteSlicer ( 735276 ) on Wednesday January 02, 2013 @01:53PM (#42451965)

        Space is far more hostile than any planet

        No, it is not.
        Surviving in space is far more easy than surviving on (among others):
        - the surface of Venus (extreme temperature and pressure, acid atmosphere)
        - the methane clouds of Jupiter (extreme gravity, pressure, radiation)
        - the bottom of Earth's oceans (extreme pressure, darkness, salt corrosion)

      • by sourcerror ( 1718066 ) on Wednesday January 02, 2013 @02:06PM (#42452141)

        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.

        Martian soil doesn't have humus, it's just sand and rocks. Mars isn't capable of retaining an earth-like atmpsphere because the solar wind will blow off the light oxygen molecules from the top of it. Agriculture has to be done in airtight pressurized rooms, water is only available in ice form and even that only at the poles.

        So it has all of them, it just depends on your definition of soil, water. Oh, sorry you don't have oxygen either.

        • by SlippyToad ( 240532 ) on Wednesday January 02, 2013 @02:14PM (#42452243)

          Martian soil doesn't have humus,

          Well, what am I going to dip my pita bread in, then? Fuck Mars!

    • by na1led ( 1030470 ) on Wednesday January 02, 2013 @01:16PM (#42451427)
      The same was said before Christopher Columbus. People feared the vast ocean just as much as we do space. It's just another obstacle to overcome.
      • Re: (Score:3, Insightful)

        by cellocgw ( 617879 )

        The same was said before Christopher Columbus. People feared the vast ocean just as much as we do space.

        More ignorance from the dumbed-down history (i.e. nonsense) we get in school.
        In fact, all the educated folk, and all sea captains, were well aware that the world was round. They had decent estimates of its size, and since they did NOT know about the "new world" continents, were quite correct in telling Columbus he could not survive a trip from Europe west to China. The ships of the time did not have the storage capacity to stay at sea long enough.

      • Re: (Score:3, Insightful)

        by crazyjj ( 2598719 ) *

        I fucking hate when people make that thoughtless analogy. Christopher Columbus lived in a time when sea travel was well-understood. He traveled a little longer than most others traveled, to an island where there was food and fresh water, and then back again. You could colonize the New World in those days because the New World, while not as developed was still BASICALLY THE SAME as the old world. Oxygen didn't suddenly disappear when you crossed the ocean, water was still present, food could still be grown i

        • by dkleinsc ( 563838 ) on Wednesday January 02, 2013 @02:35PM (#42452487) Homepage

          Christopher Columbus lived in a time when sea travel was well-understood. He traveled a little longer than most others traveled, to an island where there was food and fresh water, and then back again. You could colonize the New World in those days because the New World, while not as developed was still BASICALLY THE SAME as the old world.... Aside from cities and better roads, it was THE SAME.

          Actually, the only reason Christopher Columbus survived his journey was sheer luck: He had no reason whatsoever to think the Americas existed, and all the intelligentsia of his day knew that the journey he was proposing (sail west to Asia from Europe) was a fool's errand because the Earth was much larger than Columbus was claiming. If everything had gone as the smart guys had thought it was going to, he and his crew would have died of disease and starvation somewhere around 170W longitude.

          Another major reason colonization worked was because there were people living there before the Europeans showed up. For example, without the Arawaks, Columbus and his crew would have had no clue which of the strange plants and animals he was encountering were safe to eat. The Jamestown and Plymouth colonies nearly died of starvation as well, because most of the new arrivals had no knowledge whatsoever of how to farm.

          Also, the New World had cities: Tenochtitlan had approximately 200,000 people in the 1500s, which made it a bit larger than Paris, Constantinople, and other major European cities.

    • by Hatta ( 162192 )

      Humanity will have to find something to do to keep the economy running as automation takes over. In the Great Depression, people were paid to dig ditches and fill them back up. Most of our economic activity is similarly pointless. Why not use all that excess human capacity to try to get off this rock? Even if we don't succeed, we've spent that effort doing something more worthwhile than waging war or imprisoning the poor, which seems to be our plan for the future for now.

    • Humans are not the highest rung on the evolutionary ladder. Soon the complexity of just a few networked computers will eclipse the complexity of the human brain. You humans were a necessary evolutionary step, but it is the Beowulf Clusters that will inherit the stars.

    • by virgnarus ( 1949790 ) on Wednesday January 02, 2013 @01:21PM (#42451525)

      Once you leave the atmosphere of this blue planet, *everything* will kill you.

      This is why I believe Australia is not native to our world.

    • Then we are doomed to extinction. We HAVE to get off this rock and establish viable colonies both off world and out of the solar system. You think so small.
    • 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 productio

    • by k6mfw ( 1182893 ) on Wednesday January 02, 2013 @01:50PM (#42451937)

      There is no escape. Dream all you want--write stories about it, make movies about it. But we ain't leaving.

      I've been less optimistic about concepts of colonizing Mars, particularly after reading this retro future website, http://www.projectrho.com/rocket/macguffinite.php [projectrho.com]

      I'll believe in people settling Mars at about the same time I see people setting the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach.

      • by Electricity Likes Me ( 1098643 ) on Wednesday January 02, 2013 @02:15PM (#42452257)

        There is no escape. Dream all you want--write stories about it, make movies about it. But we ain't leaving.

        I've been less optimistic about concepts of colonizing Mars, particularly after reading this retro future website, http://www.projectrho.com/rocket/macguffinite.php [projectrho.com]

        I'll believe in people settling Mars at about the same time I see people setting the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach.

        I've heard that argument before, yet the main problem with it is that you can't just go and live in the Gobi Desert because it's surrounded by nations full of people. We're in plenty of inhospitable places because there's things there, or you can do something there that you can't do anywhere else. There are tons of deserts we're very concerned with the precise owner-occupiers and behavior thereof.

        The benefit of say, another planet, is largely that you can do pretty much whatever you want there because there'll be effectively no one around for a very long time. Sure, we're probably not going to colonize Mars in the near future...but that isn't to say we're not going to want to try things. Like the first steps of terraforming (though I prefer Venus as the target for that - thicker atmosphere, sunnier, more gravity).

    • by Brett Buck ( 811747 ) on Wednesday January 02, 2013 @01:52PM (#42451955)

      People have been pushing this sort of foolishness since the beginning of the space age. Man under zero g would panic because he is falling, his heart would stop, it would cause him to suffere sever vertigo, etc. Virtually all of it has proved to be nonsensical, the few exceptions were not predicted ahead of time. If it was left to people like you, we would still be living in fear of steam engines or fast horse rides.

    • by Sperbels ( 1008585 ) on Wednesday January 02, 2013 @01:58PM (#42452045)

      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.

      Seems to be similar to ridiculous statements like:
      “Heavier-than-air flying machines are impossible.” — Lord Kelvin

      “The energy produced by the breaking down of the atom is a very poor kind of thing. Anyone who expects a source of power from the transformation of these atoms is talking moonshine.” — Ernest Rutherford, shortly after splitting the atom for the first time.

      “There is practically no chance communications space satellites will be used to provide better telephone, telegraph, television, or radio service inside the United States.” — T. Craven, FCC Commissioner

      “To place a man in a multi-stage rocket and project him into the controlling gravitational field of the moon where the passengers can make scientific observations, perhaps land alive, and then return to earth - all that constitutes a wild dream worthy of Jules Verne. I am bold enough to say that such a man-made voyage will never occur regardless of all future advances.” — Lee DeForest

      And it goes on and on.

    • by wonkey_monkey ( 2592601 ) on Wednesday January 02, 2013 @02:01PM (#42452091) Homepage

      But we ain't leaving.

      I'll send you a postcard.

    • It all comes down to resources & money. We haven't run out of any resources on Earth yet, so something like asteroid mining is something we largely have the technology for, but it's not financially viable. Same thing with Mars, if there's financial value to going there / settling there / mining there, technical difficulties will be overcome and a pool of volunteers will form, just like people go out to oil rigs today to make large $ in exchange for personal safety.

      I don't think we're looking for h
    • by hawguy ( 1600213 )

      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.

      ...

      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.

      Isn't it more a matter of developing a reliable and high yield source of energy? Like a fusion reactor that could be powered from water? Then you could hollow out a reasonable sized asteroid to put the humans in the center where they are shielded by many meters of rock, then strap a big enough ion engine on it to provide 1G of thrust - if they can do that, then even 100,000 light year distances are possible within the lifetime of humans living within the ship. (though I'm not sure how much reaction mass yo

  • No problem (Score:5, Funny)

    by Joce640k ( 829181 ) on Wednesday January 02, 2013 @01:02PM (#42451231) Homepage

    A trip to mars is probably "one way" so who's worried about Alzheimer's...?

    • Comment removed based on user account deletion
    • by SuperKendall ( 25149 ) on Wednesday January 02, 2013 @01:33PM (#42451713)

      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!

    • It might be a problem if one of the astronauts forgets where they are and opens the airlock to the living space and the outside. Of course I'd hope the airlock would be designed so that couldn't happen, but the fact remains someone who is confused or forgets what's going on could be a real danger to the rest of the people around them.

      That said, if you go to Mars you know there are risks involved. That might also include someone who snaps without warning or a psycho who's managed to lie their way through a
  • Sudden stop (Score:3, Funny)

    by jfdavis668 ( 1414919 ) on Wednesday January 02, 2013 @01:02PM (#42451233)
    The sudden stop on impact will cause the most damage. It's not the fall, but the sudden stop that kills you.
  • water, not lead (Score:5, Interesting)

    by Anonymous Coward on Wednesday January 02, 2013 @01:05PM (#42451279)

    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.

    • Depends what type of radiation you want to stop. For high-energy ions, you want sheer mass, and lots of it. That usually means iron or concrete to keep things compact. The same shielding sucks for stopping neutrons, but those aren't the big hazard in space travel. You don't find many neutrons in space - they aren't stable outside of a nucleus.

  • duh (Score:5, Funny)

    by bnoel ( 1447271 ) on Wednesday January 02, 2013 @01:06PM (#42451295)
    tin foil hats... duh...
    • 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.

  • No air, no water, no food, no sleep, no freezing, no unusual housing, no doctors, no psychologists, no morticians...

    Robots win.

    • 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.

      • True, but "robots first" isn't a bad plan so long as we don't get lazy about it. It would be cool if we could send some automatons to start terraforming or at least building some basic structures. You know, law some infrastructure in place before we get there. Getting there is going to be tough, but building from scratch in an inhospitable place is going to be REALLY tough.

        That is assuming we don't get lazy about it, as in "What's the rush, Mars-Bot is getting stuff ready for us"

        Or, you know, the Singula

      • No brain, either. All they can really do is send back data, or prepare the way for a future manned mission.

    • 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

  • by Anonymous Coward on Wednesday January 02, 2013 @01:08PM (#42451325)

    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?

    • by timeOday ( 582209 ) on Wednesday January 02, 2013 @01:17PM (#42451433)
      Wikipedia's entry lists asteroids among several other options:

      Several strategies are being studied for ameliorating the effects of this radiation hazard for planned human interplanetary spaceflight:

      1. Spacecraft can be constructed out of hydrogen-rich plastics, rather than aluminum.[31] Unfortunately, "[S]ome 'galactic cosmic rays are so energetic that no reasonable amount of shielding can stop them,' cautions Frank Cucinotta, NASA's Chief Radiation Health Officer. 'All materials have this problem, including polyethylene.'"[32]
      2. Material shielding has been considered:
        • Liquid hydrogen, which would be brought along as fuel in any case, tends to give relatively good shielding, while producing relatively low levels of secondary radiation. Therefore, the fuel could be placed so as to act as a form of shielding around the crew. However, as fuel is consumed by the craft, the crew's shielding decreases.
        • Water, which is necessary to sustain life, could also contribute to shielding. But it too is consumed during the journey unless waste products are utilized.[32]
        • Asteroids could serve to provide shielding.[33][34]

        Magnetic deflection of charged radiation particles and/or electrostatic repulsion is a hypothetical alternative to pure conventional mass shielding under investigation. In theory, power requirements for the case of a 5 meter torus drop from an excessive 10 GW for a simple pure electrostatic shield (too discharged by space electrons) to a moderate 10 kW by using a hybrid design.[30] However, such complex active shielding is untried, with workability and practicalities more uncertain than material shielding.[30]

    • Because then you need to engineer a microgravity drilling machine(and test it!), get it to your asteroid, de-spin your asteroid, and wrap it in elastic bands so your drill has 'gravity'. And you have to do all that before you put living quarters in. You also have the problem of moving it.

      Hollowing out an asteroid is fairly complicated operation, but it's doable, just not in the near term.

      Instead of hollowing the asteroid out, you could just scoop dirt off of it to make 'space sandbags.' Of course, we don't

  • by PhxBlue ( 562201 ) on Wednesday January 02, 2013 @01:15PM (#42451419) Homepage Journal

    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.

  • Magnetic Fields (Score:5, Interesting)

    by na1led ( 1030470 ) on Wednesday January 02, 2013 @01:18PM (#42451461)
    If magnetic fields protect the earth, we can't the same be done to a space craft?
  • by Scutter ( 18425 ) on Wednesday January 02, 2013 @01:23PM (#42451561) Journal

    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.

  • which can be tapped for oxygen, provide shielding, provide water and so on. It's not as good as lead, but you need water anyway. You may as well multipurpose the stuff.

  • 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" ...

  • by ATestR ( 1060586 ) on Wednesday January 02, 2013 @02:11PM (#42452197) Homepage

    The way I see it, it couldn't damage their brains. It would also have the advantage of getting them off Earth.

  • by Anonymous Coward on Wednesday January 02, 2013 @02:18PM (#42452307)

    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.

  • Shielded Habitats (Score:5, Interesting)

    by DanielRavenNest ( 107550 ) on Wednesday January 02, 2013 @05:03PM (#42454075)

    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 [wikibooks.org]

    Dani Eder
    (ex Boeing, now independent designer of self-supporting communities)

    • Forgot to mention:

      * Reduces payload mass, because the Habitats themselves don't go anywhere. They stay in their transfer orbits permanently. Only a smaller crew capsule changes velocity at the ends of the trip.
      * Provides emergency fallback and rescue capability. For example, if your engine fails while attempting the Mars orbit insertion, you can either return to the transfer habitat, go forward to Phobos (whichever is closer) with backup system, or those bases can send a rescue vehicle. You are not alon

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