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Space Science

A Mars Mission's Greatest Challenge: Radiation 417

daSeiz writes "A New York Times article explores the possible effects of prolonged radiation exposure in deep space. Surprisingly, very little is known about the subject. We'll need to find innovative new ways of shielding spacecraft from fraction-of-lightspeed interstellar rubbish if we're ever to spend much time outside our own magnetosphere."
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A Mars Mission's Greatest Challenge: Radiation

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  • by PatrickThomson ( 712694 ) on Tuesday December 09, 2003 @02:44PM (#7671504)
    Tinfoil hats!
    • by tds67 ( 670584 ) on Tuesday December 09, 2003 @02:59PM (#7671725)
      Tinfoil hats!

      To hell with that--lead jock straps!

    • by saskboy ( 600063 ) on Tuesday December 09, 2003 @03:19PM (#7671951) Homepage Journal
      Actually, my research last year on what it would take to get to Mars turned up that a very long hydrocarbon chain, like the hydrocarbons in plastic shopping bags, were the best way to transport lots of hydrogen atom shielding into space in a fine powder so it could be mixed into hydrogen clay with water at Mars.

      There are also hydrogen material bricks in some sleeping stations on the ISS, I think they were first used on MIR.

      This low-tech shielding was the inspiration for part of the filtering my Foil Hat in my sig.
  • Judging (Score:4, Insightful)

    by duffbeer703 ( 177751 ) * on Tuesday December 09, 2003 @02:45PM (#7671513)
    By the lack of consistent success in getting small probes to the red planet, I'd have to say that rushing out a manned mission should NOT be a priority.
    • Re:Judging (Score:4, Insightful)

      by kippy ( 416183 ) on Tuesday December 09, 2003 @02:53PM (#7671636)
      Wrong. It should be a priority. Do you think we'll develop tech to sheild us from radiation if we have no plan on going there? NASA needs to set a goal and develop the tech to get there.

      If your attitude was around when we were all still in Africa, we'd all still be there because developing clothing is just too darned hard.

    • Re:Judging (Score:5, Insightful)

      by wolenczak ( 517857 ) <<paco> <at> <cotera.org>> on Tuesday December 09, 2003 @02:56PM (#7671678) Homepage
      Perhaps we could create a magnetic field pretty much like earth's to protect the spacecraft/station. Leaded materials are not an option, unless mars has a source of minerals that could be used to build the shielding. Anyway space research should be a priority. Many of the appliances and materials you use everyday use technology developed thanks to space research.
    • by crow ( 16139 )
      Comparing the potential success of a manned mission to that of unmanned missions isn't valid. With a manned mission, the margins of safety are completely different.

      With an unmanned mission, they can save weight and money by not including redundant backup systems. It's cheaper to send two probes and have one fail than to send one probe with redundant backups on all systems. With a manned mission, everything changes. Systems have backups. Margin for error is reduced.

      Perhaps in old Soviet Russia... :)
  • Moon kooks... (Score:2, Informative)

    by Threni ( 635302 )
    ...love all this! they think radiation is what made the lunar landings impossible and therefore obviously faked!
  • Comparing Price (Score:5, Insightful)

    by jaaron ( 551839 ) on Tuesday December 09, 2003 @02:45PM (#7671526) Homepage
    Others include price, estimated at $30 billion to $60 billion, and launching enough food, supplies and fuel for a round trip. Any one of these could make the project impractical.

    Well, not to sound too bitter, but going to Mars seems like a much better way to spend billions than going to Iraq.
    • All George Bush needs to do is say that he has evidence (don?t say what it is) of weapons of mass destruction on the mars surface. Then he can get as much funding as the project needs.
    • Re:Comparing Price (Score:2, Insightful)

      by pr0t0plasm ( 183810 )
      Right on. Before heading to Mars, though, might it not make sense to build some space infrastructure? A waypoint at L2, an LEO station large enough to be useful for constructing further spacecraft in orbit, or any other such project would be less flashy, but perhaps more enduring in its influence.
  • by Prince_Ali ( 614163 ) on Tuesday December 09, 2003 @02:45PM (#7671528) Journal
    Every sensible person knows that a space craft that is shielded enough, and large enough to allow a human to survive outside our magnetosphere would be too heavy to reach escape velocity. That is why a human has never left Earth's orbit... Apollo indeed!

    I've done the math. It would take shielding 100x stronger than the stuff I use to build the hats that keep the psychotronic weapons from affecting my brain!

    • It should be noted that "heavier" doesn't always mean "better" radiation shielding in space.

      Hydrogen, the lightest atom, makes one of the best shields, because it doesn't kick out radiation very well after being struck by a high energy atom from the Sun.
  • by account_deleted ( 4530225 ) on Tuesday December 09, 2003 @02:47PM (#7671541)
    Comment removed based on user account deletion
  • by Ba3r ( 720309 ) on Tuesday December 09, 2003 @02:47PM (#7671547)
    Ready.gov [ready.gov] has plenty of useful information on radiation shielding. If you have a thick shield between yourself and the radioactive materials more of the radiation will be absorbed by the thick shield, and you will be exposed to less. Perhaps NASA could use some insightful advice from the Dept of Homeland Securty. I bet a couple rolls of duct tape and some plastic would be quite useful in Space!
  • by Anonymous Coward
    Just reconfigure the modulators.
  • Whoa, dude. (Score:5, Funny)

    by shystershep ( 643874 ) * <.moc.liamg. .ta. .drehpehsdb.> on Tuesday December 09, 2003 @02:48PM (#7671566) Homepage Journal
    changes in motor skills are tested by stimulating animals with cocaine and measuring movement with infrared beams

    They tried marijuana first, but the mice just got paranoid and started eating everything in sight.

  • by rf0 ( 159958 ) * <rghf@fsck.me.uk> on Tuesday December 09, 2003 @02:49PM (#7671574) Homepage
    Well we will have to reroute main engine power through the deflector dish to create a graviton feedback wave which will in turn allow us to turn the radiation into a non-harful form of chocolate

    Rus
  • And of course I'll wear a pair 'o
    Levis, over my lead BVDs.

    (Slightly different context, but hey.)
  • Bone loss (Score:5, Insightful)

    by hcuar ( 706760 ) on Tuesday December 09, 2003 @02:51PM (#7671610)
    Ummm... Actually, wouldn't the worst problem be bone density loss. That's one of the main problems on the ISS (International Space Station). Without the effect of gravity, bone density decreases. From what I understand it's a pretty nasty recovery. The time required to go to and from Mars plus mission time would require much more time in space than any ISS mission to date.
    • The biggest problem will most likely be weakening of the immune system. Spend enough time in space, and your immune system will be about as effective as that of someone with AIDS. Fortunately, the effect reverses itself quickly once you're back in a decent gravity field.
    • Re:Bone loss (Score:2, Informative)

      by donnyspi ( 701349 )
      I was curious how long it would take to get to mars and back. Here [vanderbilt.edu]'s the answer:

      "A mission to Mars would take about three years from launch to reentry, including 6-12 months of travel each way and a lengthy stay on Mars while the planets reach optimum position for beginning a return flight. (NASA)"

    • Re:Bone loss (Score:3, Informative)

      by catfry ( 730592 )
      Actually I believe many of the astronauts on the ISS claim that the loss of bone mass has been drastically reduced with the kinds of excercises they are doing on a daily basis. Although the problem hasn't been completely eleminated read for example this letter from expedition 7 crewmember Ed Lu [slashdot.org]. "We have some indications that we may be close to solving the problem. In fact, one of our main goals this mission is to see if we can replicate the very good results obtained by some previous ISS crew members in pr
  • by Janek Kozicki ( 722688 ) on Tuesday December 09, 2003 @02:52PM (#7671616) Journal
    this problem is known, and Mars Society [marssociety.org] already has some solution [marssociety.org]for this problem.

    Anyway if you also wanted to know about radiation on the planet Mars, be sure it is not [marssociety.org] dangerous.
  • by downix ( 84795 ) on Tuesday December 09, 2003 @02:53PM (#7671632) Homepage
    $30 to $60 billion to get to Mars? I know how to do it. Tell Dubya that Martians are stockpiling weapons of mass destruction!
  • by TonyZahn ( 534930 ) on Tuesday December 09, 2003 @02:54PM (#7671650) Homepage
    Ok, IANAP, but what would be the requirements to build a device capable of generating a magnetic field similar to the earth's magnetosphere? I would imagine that it's more efficient to generate a powerful magnetic field around a spaceship than it would be to line the whole thing with lead bricks...

    Would the energy requirements be far to high, or maybe the diameter has to be a certain size to deflect solar radiation around the ship? This is all pure non-researched speculation of course, but I know that there's more than a few intelligent /.s out there who may be able to answer this.
    • by GileadGreene ( 539584 ) on Tuesday December 09, 2003 @03:04PM (#7671783) Homepage
      I think you'll find that your questions will be answered by a look at this [washington.edu] site. It's all about Mini-Magnetospheric Plasma Propulsion (M2P2). They do exactly what you are asking for (create an artificial magnetosphere), and supply some nifty propulsion to boot. And no, it doesn't require megatons of molten iron, as some other posters have suggested...
    • Lead bricks have the advantage that they'll stop other things, like small meteors, in addition to the radiation.

      Not to say that magnetic shielding doesn't have benefits. Google for "magsail" or "magnetic sail".
    • Earth's magnetic field deflects most of the nasty particles eventhough it is weak because it is huge. To do the same on a smaller scale would require a much stronger field. Probably too strong to create with the available power a spacecraft might have. You only have to shield what you really need to protect (the occupants) and that could be done (as is done on the space station) by having a small, well-shielded room to duck into when the need arises. There are new multi-layered shielding materials that are
  • Bring along a magnetosphere.
  • by RealProgrammer ( 723725 ) on Tuesday December 09, 2003 @02:57PM (#7671696) Homepage Journal
    Intermittently, an assistant went into the heavily shielded target room to adjust the target, a procedure that requires a retina scan by a security device and the insertion of special keys to assure that no one unauthorized enters.

    It would take more than a neuralizer to get me to go in there.

    I wonder where on the assistant they insert the special keys?

  • Water (Score:3, Insightful)

    by AKAImBatman ( 238306 ) <akaimbatman@gmaiBLUEl.com minus berry> on Tuesday December 09, 2003 @02:57PM (#7671697) Homepage Journal
    Water is one of the best radiation protectors. By filling the double hull with water (and compartmentalizing against breaches) you could effectively shield an entire crew. Some form of EM "bubble" technology would also work, but it would be much more difficult to implement.

    Oh, and they should use nuclear engines like NERVA or Orion. That way the extra weight of the water is less important, not to mention that the craft may be able to reserve enough fuel for emergency maneuvers.

  • Problems Like This (Score:5, Interesting)

    by ChuckDivine ( 221595 ) * <charles.j.divine@gmail.com> on Tuesday December 09, 2003 @02:58PM (#7671700) Homepage

    I do remember from my O'Neill colony advocacy days that people who knew more about the subject than I did recommended putting heavy, static shields around the colonies. One meter or so of solid waste products (think left over materials from mineral refining) in a layer around the colony could effectively shield the inhabitants from cosmic radiation.

    This, unfortunately, makes for a pretty massive structure -- difficult to move around the solar system with contemporary propulsion. Travel is possible, especially with better propulsion, but more difficult than Star Trek et al. would have you believe.

    This problem also could impact those proposals for Martian bases and settlements. I think Mars doesn't provide the same protection from radiation as Earth does. So, we could build bases on Mars -- just bury them underground. That's hardly what I think Zubrin and company want.

    It might be interesting to see what can be done, if anything, with some sort of magnetic shielding. Although that could be a lot trickier again than SF TV shows imply.

    I think problems like this are resolvable, but it's going to take a wide variety of efforts in multiple fields and directions to come up with solutions. Is there enough interest in space currently to make that kind of effort? Or can research in various fields be done with other goals in mind to solve this specific problem?

    • You're going to have to bury the bases underground until you can thicken the atmosphere :)
    • by bravehamster ( 44836 ) on Tuesday December 09, 2003 @03:17PM (#7671933) Homepage Journal
      just bury them underground. That's hardly what I think Zubrin and company want.

      Umm...guess you haven't read his book. That's *exactly* what Zubrin wants, and advocates in his book "A Case For Mars". Just because someone wants something very badly does not mean they are blind to the realities of their dreams.

    • by Ungrounded Lightning ( 62228 ) on Tuesday December 09, 2003 @03:51PM (#7672362) Journal
      I do remember ... people ... recommended putting heavy, static shields around the colonies. One meter or so of solid waste products ... could effectively shield the inhabitants from cosmic radiation.

      This ... makes for a pretty massive structure -- difficult to move around the solar system with contemporary propulsion.

      One alternative that has been considered is an Apollo asteroid shuttle.

      * Take one of the Apollo asteroids (which have orbits that cross that of earth).

      * Modify its orbit so that it shuttles between the orbits of Earth and Mars, arriving near each when the planet is also nearby. (Use solar sails or solar-powered mass drivers or ion accellerators throwing spare mass from the asteroid for propulsion, to get your delta-v without hauling up fuel.) Takes a while, but can be automated for most of that time.

      * Build a base INSIDE the asteroid.

      The asteroid provides the mass of shielding, plus raw materials for buildings and a mostly-closed ecosystem. It becomes an "orbital hotel", much like an interplanetary cruise ship, making a trip every couple years.

      Once it's established you only need enough delta-v to get your passengers and freight between the planets at the end of the trip and the asteroid. This is the same amount of fuel as shipping them and their docking shuttle to Mars or back by the same orbit - but you DON'T need to ship their well-shielded vehicle or most of their consumables. MUCH cheaper. Radiation exposure in the hypothetically less-shielded shuttle is for a few hours at the ends of the trip, rather than for a couple years during the trip.
  • A New York Times article explores the possible effects of prolonged radiation exposure in deep space. Surprisingly, very little is known about the subject.

    They've obviously never read the Fantastic Four.
  • by psxndc ( 105904 ) on Tuesday December 09, 2003 @02:59PM (#7671719) Journal
    You know one will come back all bendy-like, one will be on fire, another will be invisible, and one will be made of orange rock. And I ain't even a PhD.

    psxndc

  • We'll need to find innovative new ways of shielding spacecraft from fraction-of-lightspeed interstellar rubbish if we're ever to spend much time outside our own magnetosphere...

    I think you meant LARGE fraction of lightspeed interstellar rubbish. The spitballs my cubicle mate hurls at me are fraction-of-lightspeed rubbish. A very small fraction of lightspeed. Shielding requirements are minimal.

    How, though, will we protect ourselves from the terrible secret of space?

  • by jridley ( 9305 ) on Tuesday December 09, 2003 @03:01PM (#7671747)
    What you really have to worry about is mid-energy stuff coming from the sun during a flare; that will bake you in a couple of hours. Luckily you just need a meter of water or so and you're good, so you can have a hidey-hole in the core of the ship to duck into for a few hours during flares, which you can get a warning of.

    There's not much you can do about cosmic rays in a ship; you can't economically carry that much shielding, but luckily it's pretty low flux; a Mars mission would, by the estimates I've seen, raise a participant's lifetime chance of dying of cancer by 2%.
  • by wowbagger ( 69688 ) on Tuesday December 09, 2003 @03:01PM (#7671753) Homepage Journal
    The problem is finding a shielding material that will absorb the radiation that will affect a human body, without transmuting radiation that would pass harmlessly through a human into radiation harmful to a human. Thus, you need a shielding material that is cheap and has the same absorbsion parameters as a human.

    I suggest using spammers.
  • Livin Underground (Score:4, Interesting)

    by avkillick ( 698274 ) <avkillick&yahoo,com> on Tuesday December 09, 2003 @03:01PM (#7671756) Homepage
    All the futurists depict Martian/Lunar colonies as above ground structures/modules launched from Earth. I am convinced that humans and robots that wish to remain permanently on the moon or Mars will need to bury themselves underground to protect themselves from the radiation. Further, I believe that as a precursor to these permanent outposts, we will send up mining robots to develop the required infrastructure.
  • by GillBates0 ( 664202 ) on Tuesday December 09, 2003 @03:07PM (#7671818) Homepage Journal
    A third area of research is shielding. On Earth, radiation shielding is commonly provided by concrete or lead, but the costs of launching spacecraft are so high that this is not practical. One possible solution is a water tank, with the astronauts' living in a chamber in the middle. "It's just so expensive to put material into orbit that you'd like to use materials you have to bring anyway," Dr. Lowenstein said.

    I propose a solution to this problem. The main problem with launching rockets/satellites is exactly that -- launching them...i.e. generating enough power to achieve escape velocity required to overcome the Earth's gravitation force.

    An alternate approach, however, would be to use the planet itself as a spaceshuttle for the reasons below:

    1. Capable of high velocity:
    The Earth is capable of travelling at very high speeds (currently 18.55 miles/sec) without causing noticeable discomfort/grievances to the passengers (astronauts).

    2. Strong shield against radiation: The Earth's atmosphere provides a strong shield to protect the astronauts from high amounts of radiation present in outer space.

    3. Fuel efficient: The planet is extremely power efficient at converting the energy generated due to the gravitational interaction between planetary bodies into rotational/revolutionary motion.

    4. Huge storage area: The proposed space shuttle provides a huge hold/storage area capable of holding large amounts of food/water and other resources. The storage areas are regenerative, in that they help degrade waste into material which can be used to reproduce useful material.

    The only area which needs research is navigation--figuring out how to make the Earth go where we want. I think that's what NASA/etc should focus on now.

  • by Per Abrahamsen ( 1397 ) on Tuesday December 09, 2003 @03:08PM (#7671827) Homepage
    Statistically, 25% will be able to invisible at will, 25% will be transformed into big stone monsters, 25% will be able to turn into flames without getting hurt, and 26% will be able to stretch their body many times its normal length.

    There are 1% uncertainty on these numbers.
  • by Mysticalfruit ( 533341 ) on Tuesday December 09, 2003 @03:08PM (#7671828) Homepage Journal
    There was a story on space.com last week about how NASA was testing a new material that could be woven into space suits and used in the construction of spacecraft, etc... Inital testing had shown it could effectly block most/all radiation or turn it into a form that isn't harmful.

    Here's the link: link [space.com]

  • Bill Gates truly is a very generous man (giving away billions through an orginization run by his father), and those that he has helped out I'm sure are very thankful he did help them... but it's time to focus on the big picture Bill!

    Donate say, $20 - $30 billion to NASA (or hell, just donate a piddly $10 billion) for a mission to Mars. Hell, Microsoft has $40 billion in the bank, why not use some of that? Yeah, we'll have to have everything running Windows 2010, but as long as you don't require the computer to be named HAL (or BILL for that matter) I think everything will be ok.

    Even though many contend you're evil, you'd be just slightly less evil in the eyes of every true geek out there.
  • by demachina ( 71715 ) on Tuesday December 09, 2003 @03:19PM (#7671956)
    As the article indicates this is not that much of a problem if you design the crew compartment, or at least part of it, with a second hull and fill it with water which you'd use when you get there anyway. The major challeneges are:

    - a pretty major propulsion system to get a heavy ship headed to Mars at a high rate of speed, presumably nuclear
    - getting a lot of mass into LEO in the first place

    It doesn't bode well for a new Moon or Mars mission that NASA can't even get mass in to orbit in a reasonable way. As I've said before throwing a bunch of money into NASA for a new space initiative is not a good idea. As the shuttle and ISS show NASA has developed fundemental institutional flaws which tend to result in large amounts of money being spent and not much being accomplished. To think you're just going to set a new goal and get a better outcome, with no structural change, is naive. Set up a new skunkworks if you want to accomplish something in space, hire the best people and reward them in a meritocracy, not a bureaucracy.

    This article is also flawed in the same way as most discussions of a Mars mission. The goal SHOULD NOT be a round trip. The goal should be to start sending big unmanned cargo ships, carrying water, food, habitats, green houses and nuclear power plants to Mars and when they are arriving reliably send colonists on a fast one way trip to stay for the duration. The other major challenge finding men and women who are compatible and are willing to produce future versions of the colonists.

    Spending 60 billion to send a few astronauts to pick up rocks and come back just isn't worth it. Apollo kind of proved this. As soon as landing on the moon had been done, missions to pick up rocks didn't hold public support.

    A permenent colony is also kind of an underhanded way to insure long term funding for the program since once you have colonists on Mars you are going to have to do whats necessary to keep them alive, until they are self sufficient (though they may not be fully self sufficient for a long time for manufactured goods like electronics).

    Once you have a self sustaining colony you are insured a perpetual mission and are free of the whims of whether Mars 18 will be funded or not.
  • give the ship its oen magnetosphere, as it were.

    There, another problem solved. Someone tell the engineers I need it by friday.
  • by GirTheRobot ( 689378 ) on Tuesday December 09, 2003 @03:32PM (#7672095)
    "In a new $34 million NASA laboratory here, part of Brookhaven National Laboratory, scientists are using subatomic particles accelerated to nearly the speed of light to slam into materials that could be used in a spaceship, and tissue samples and small animals. Using tools like PET and M.R.I. scans and DNA sequencing, they hope to shed light on ways that radiation damages biological tissue, and what can be done about it"

    Today: NASA puts cuddly animals in particle accelerators...tomorrow: world destroyed by giant mutant rodents!!!
    Why isn't PETA having a field day with this???
  • by sbma44 ( 694130 ) on Tuesday December 09, 2003 @03:33PM (#7672112)
    All you really need here is dense mass. The problem is getting that dense mass into space, moreso than it is propelling the mass to mars once it is in space.

    If we do go ahead with the administration's somewhat-ridiculous moon base idea, we could just launch some carved lunar rock shields -- perhaps encased in a polymer to prevent micrometeor-induced fractures. Throw those off the surface of the moon for much less energy and attach them to the mars craft at Lagrange or in orbit. Get a slow but steady start helped by some gravity slingshotting and you're on your way to mars.

    I'm sure there are slashdotters with a stronger grip on rocket science than I have (which is basically limited to F=ma). Is this feasible? Or would it make more sense to just pay for firing lead/water into space from earth?

  • by YllabianBitPipe ( 647462 ) on Tuesday December 09, 2003 @03:35PM (#7672137)
    Seems to me it would make sense to return to the moon and establish a base there. Practice mining for materials, building a liveable environment, grow food. Basically set up a biosphere type environment on the moon, then worry about Mars. Next, I would imagine launching a mission to mars could be in some cases easier from the moon. Less gravity, tested equipment, people used to the idea of living off earth. And to echo another poster, why not send robots for a couple of missions well in advance to set up stuff, start mining, building shelters so when the people get there they don't have to cart a ton of stuff with them.
  • the truth (Score:4, Interesting)

    by Geno Z Heinlein ( 659438 ) on Tuesday December 09, 2003 @03:38PM (#7672173)
    We'll need to find innovative new ways of shielding spacecraft from fraction-of-lightspeed interstellar rubbish if we're ever to spend much time outside our own magnetosphere.

    Great, space FUD.

    I recommend The Case For Mars (amazon.com link) [amazon.com], by Robert Zubrin. You can also check out The Case For Mars [colorado.edu] website.

    The short version is this: we have all the technology we need to safely colonize Mars right now, and with less danger and hardship than the American colonists suffered four centuries ago. If funding were allocated today, the first scientists could be on Mars in 10 years, and colonists in perhaps 20. (The money required would be a small fraction of the US civilian-bombing budget.)

    Safety from radiation is easy. Zubrin points out that you can just go to the center of the ship and stack your supplies around you to reduce radiation to acceptable levels, even in the case of a powerfuil solar flare. On the surface, you just build homes underground for everyday living. People here on Earth are doing this now just for the energy-bill savings. I think we can do it in order to colonize an entire planet.
  • Demron? (Score:3, Insightful)

    by F34nor ( 321515 ) on Tuesday December 09, 2003 @04:05PM (#7672538)
    Why not wall paper the inside of the ship with Demron [sciam.com] for the outside use a the foam/armid lamiante process developed for the Cassini probe for the outer shell. All of it could be made out of plyable frabrics and assempled in space. No metal, so its easy to bring up on ship rolled up in bolts of cloth, the foam can come up as a liquid. Just a big ass micrometor and radiation proof ball with a truster on one end. Let it spin and even hav a parital G for the ride.
  • Not the only issue (Score:4, Interesting)

    by Pedrito ( 94783 ) on Tuesday December 09, 2003 @04:13PM (#7672621)
    This is only one of many issues.

    Human bones become brittle in less than 1G environments, after extended time. The time it would take for a mars mission, given current technology, the damage to astronauts would probably be irreversible for all but a short-stay mars mission.

    Bone loss in zero G is about 10% per year. 10% is a lot of bone loss.

    A short-stay mars mission is where you only stay on mars 30-90 days, and total mission time runs between 400 and 650 days. This may be long enough to do permanent damage.

    A long-stay mars mission has a round-trip time of about 900 days. Even with half of that spent on mars, the combination of the extended stay in low G combined with the other half in zero G will turn most people to jelly. You're probably looking at around 25% bone loss here.

    Not just the bones you normally think of, but your teeth will rot and fall out as well with these kinds of trips.

    Even with exercise, muscles, ligaments, and tendons will atrophy significantly.

    The plain fact is, human beings weren't built for space travel. By providing an artificial gravity (which would therefore mean a larger ship to shield), you can get by this, but then you're adding weight, which adds fuel and time, and so forth.

    I personally don't think we're ready for a mars mission any time soon. Probably not in my lifetime. We ought to concentrate on closer targets until we have the technology to send people to mars safely.
  • by fiannaFailMan ( 702447 ) on Tuesday December 09, 2003 @04:41PM (#7673063) Journal
    All they have to do is reconfigure the main deflector array to emit a polarised field of nanotachyons and redirect 20% of power from the EPS conduits to make sure that the ship maintains a stable warp field without compromising the counter-radiation shielding. Like, duh!
  • by praedor ( 218403 ) on Tuesday December 09, 2003 @04:42PM (#7673075) Homepage

    from that kook, Erik Von Daniken of Ancient Astronauts fame? In one of his interpretations of a Mayan carven rock image, he sees an astronaut in a reclined position operating instruments. Outside the "vehicle" he sees a rocket plume, etc. The thing is, and I always wondered about the possibility of this working, he produced an "engineered" drawing of the "spacecraft" and added annotations. One of them indicated a magnetic shield around the spacecraft.


    Since way back when Ancient Astronauts was new and I saw that drawing, I have wondered about that idea. Could you not generate a magnetic field around your spacecraft so as to deflect charged high speed particles? You could also use water shielding. Water tanks could be placed to completely encircle the crew compartment(s)/living quarters and act as shielding as well. So...what about combining an artificial ship's magnetic field and water shielding?


  • it's so obvious! (Score:3, Informative)

    by MOMOCROME ( 207697 ) <momocrome@gm[ ].com ['ail' in gap]> on Tuesday December 09, 2003 @04:43PM (#7673108)
    There is a drive technology called "Mini-Magnetospheric Plasma Propulsion [washington.edu]", or m2p2, that in effect creates a large scale magnetic bubble around a spacecraft.

    In the current incarnation, it is intended as a solar-sail like drive for very low-mass probes. However, attached to a larger mass, like an interplanetary vehicle of the scale suitable for human occupancy, it would barely impart momentum at all, which would make it unsuitable as a drive technology.

    Though it would work wonderfully to shield the vehicle from the solar wind and other problematic radiation.

    The crazy thing is, though a portable magnetosphere is so obviously a crucial requirement for trans-planetary travel, there isn't a single resource available through my above-average googling skills. The technology is either so far removed from mainstream mission planning circles, or...

  • by karlandtanya ( 601084 ) on Tuesday December 09, 2003 @04:45PM (#7673135)
    What's the point?


    What's the point of: Publicly Funded Art? Big Science? Pure Science? Exploration? Going to the Moon? Going to Mars? SETI? Falling in love? Climbing a Mountain? (last one's a clue)


    You will find many "justifications" for such endeavors--many of which are to the scale that they must be publicly supported (funded) if they are to happen at all.


    They are just that. Justifications. Rationalizations of a decision after the fact. All the justifications offered for these acts are BULLSHIT.


    The reason we do these things is "because". Peroid. This is the concept of intrinsic value.


    Think about this for a moment. If we do something--anything, we give a reason. I go to work to make money. I make money to buy things. I bought a car to go to work. But what do all these things get me? In the free time that I have when I'm done working, when I'm done driving, what do I do?


    Love? Learn? Raise children? Why? What do these things get me?


    Nothing except themselves. They have value because I say they do. Nothing more. There is no "purpose" for love. There is no purpose for "Going to Mars".


    Sure, we got useful stuff--national pride (some think that has value), new technologies, etc. from our trip to the moon.


    But that's not why we did it.


    We did it because it was hard. And it would be cool to have done it.


    That's what makes us what we are. The things we do "just because". Not because we have to or because they are a means to an end. Just because we think they would be cool to do.


    Intrinsic value is by definition subjective. If there's no justification, then there's no logical argument I can provide that says the things I value are the things you value.


    But, as a society, there are some "great things" we can do.


    The challenge of doing a "great thing" is not the doing of the thing (solving the radiation problem). The challenge is getting enough committed people together--through social imperatives (taxes, congress) or consensus--to actually get up and do it


    Why do you climb a mountain?


    Becuase it's there.

  • by CSG_SurferDude ( 96615 ) <wedaa.wedaa@com> on Tuesday December 09, 2003 @04:49PM (#7673190) Homepage Journal
    While putting people in orbit is tricky and expensive, there is a way to put food and water into space very cheaply: Superguns! [friends-partners.org]

  • by MythoBeast ( 54294 ) on Tuesday December 09, 2003 @04:58PM (#7673327) Homepage Journal
    This may seem naive, but what prevents us from including a magnetic core in our interplanetary space craft? The weight for that kind fo thing has to be a lot less than the weight of sheilding.
  • by VernonNemitz ( 581327 ) on Tuesday December 09, 2003 @06:34PM (#7674543) Journal
    The answer is to design the Mars transit vehicle to carry its own magnetic field. Superconductors allow us to create fields of such strength that just about any cosmic ray will be bent to miss the spacecraft. Also, we can inject some local ions into that magnetic field, trapping them, and they in turn act as a partial shield against electromagnetic radiation (charged particles and photons have a nice high interaction probability). For more, and on even using such magnetic fields as a modest propulsion mechanism (interacting with Solar Wind), see this [washington.edu].

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