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Mars Space Science

Cosmic Rays Could Kill Astronauts Visiting Mars 722

jvchamary writes "Given the recent stream of reports of 10th planets and the relative success of the NASA Discovery mission, it might again be time to get excited at the prospect of visiting the Red Planet. Unfortunately, New Scientist reports that Astronauts traveling to Mars would be exposed to so much cosmic radiation that 10% would die of cancer."
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Cosmic Rays Could Kill Astronauts Visiting Mars

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  • by BlackCobra43 ( 596714 ) on Wednesday August 03, 2005 @01:43PM (#13232093)
    Not only is it cancer, it's space cancer. That's gotta be like 10 times worse ;)
  • Use some lead plating in those suits. That'll protect 'em! ;-)
    • Its easier to wear lead-shoelding on Mars because the force of gravity is lower.
    • No, lead is insufficient. They'll need something heavier, like Urani... oh.
    • by SuperBanana ( 662181 ) on Wednesday August 03, 2005 @01:55PM (#13232283)
      Use some lead plating in those suits.

      I know you're joking, but I think a number of slashdot readers are thinking, "yeah, why can't they just shield them".

      • They'd have to be wearing quite a bit of lead shielding. Thousands of pounds, in fact. A fair chunk of cosmic radiation consists of ionizing, high-energy radiation.
      • Additional shielding, either for people or the entire craft, would require more fuel to accelerate to the necessary travel velocity- and more fuel to SLOW DOWN when you get there. The bits that were involved in landing couldn't be shielded, as the weight would make it a one-way trip (it pretty much is anyway).
      • A magnetic field to deflect said particles (aka like the earth's field) would require a lot of energy, which could only come from a nuclear source. Which would emit its own radiation, require its own shielding,, would add weight to the craft.

      I'm not sure I see the point of even going to Mars in the first place; like Kennedy's moon trip, going to Mars will get us nothing. Things are just too impractical to get anything useful done on either planet. The futurists all argue, "well, SOME day it'll be practical". Wasn't this the same group that predicted we'd have, ten years ago, flying cars, transporters, faster than light travel, etc?

      • I wouldn't say that the moon race got us "nothing". A ton of technology came from the space race. Sure, it may be been developed for other purposes, but surely not as quickly.

        Can you imagine the technology that a "Mars race" could spawn? New kinds of environment control. New kinds of waste scrubbing technologies, new kinds of filtering and recycling, etc... It could be big.
      • No prob... have the nuclear reactor a few thousand feet away from the crew capsule on a tether or girder. let it generate the massive magnetic shield. it can happily radiate away at a safe distance.

        heck, why cant we use an ablative shielding in a super large "jiffy pop" bag behind the craft? a chemical reaction that creates a large metallic "sponge" with lots of crevices and surfaces to slow down or stop that radiation? if you have a crap load of surfaces (bubbles in the metallic sponge) your radiation
    • Often, the difference between 'problem' and 'expense' is a function of your budget. In the case of the Mars mission, the only thing that's funded is a little bit of planning. Everything else is unfunded, so everything else is a problem.

      In fact, many things that don't have to do with Mars have become problems, because Mars has been leaching dollars from other programs. So, for example, the Hubble Space Telescope, the single most scientifically valuable instrument in space, has become too expensive to re

    • by mrjb ( 547783 ) on Wednesday August 03, 2005 @02:56PM (#13232928)
      Let them breed. The 90% that survives are obviously more cancer-resistant than the others. In a few generations, cancer rates will be at acceptable levels.
  • by the darn ( 624240 ) on Wednesday August 03, 2005 @01:44PM (#13232106) Homepage
    Also, 25% will become stretchy, 25% will turn invisible, 25% will burst into flames, and 25% will have their skin replaced by an orangey rock-like substance!
  • by eklitzke ( 873155 ) on Wednesday August 03, 2005 @01:44PM (#13232112) Homepage
    We only send nine :)
  • Risk v. Reward (Score:5, Interesting)

    by Shadow Wrought ( 586631 ) <shadow,wrought&gmail,com> on Wednesday August 03, 2005 @01:45PM (#13232118) Homepage Journal
    So how would this be a limiting factor for a government that still subsidizes tobacco farmers? What if we only sent smokers? TFA article says that 10% would get fatal cancer sometime in their lives. Really, how is this different from those who self select themselves for a much increased risk of cancer through smoking?
  • Can we not desing the spacecraft and the spacesuits to block radiation? Such things exist here on Earth. Is cosmic radiation different than radiation here on earth?
    • Yes, there's a lot more of it in space (including fancy gamma rays), and there's generally a very small mass budget for shielding.
    • Yeah, the amount of radiation in a nuclear plant is ooooh about on par with the sun.

      Those suits don't even completly protect from the small nuclear sources on the earth, let alone a whole fucking sun+stars+everything else in the universe. If it was such an easy solution, why do you think people are worried about it?
    • by Shaper_pmp ( 825142 ) on Wednesday August 03, 2005 @01:55PM (#13232276)
      Basically, yeah - we have several miles of comparatively dense atmosphere (or the entire bulk of the earth) protecting us from cosmic rays. Future Mars astronauts will pretty much have a few layers of tinfoil.

      Still, it is possible to design ships which will shield passengers from the worst of the rays, but these tend to be prohibitively heavy (= prohibitive amounts of fuel) because of all the additional shielding.

      The best alternative I've seen yet were plans to build a ship where all the water and other supplies were stored around the outsides of the ship, and the actual crew living compartment was a small space right in the middle - this uses water and fuel (the bulkiest of the supplies) as additional shielding, but it still carries a much elevated risk of irradiation and/or cancer than staying put on earth.
  • Is this news? (Score:5, Informative)

    by pcmanjon ( 735165 ) on Wednesday August 03, 2005 @01:45PM (#13232123)
    We've known this for quite a while.

    I think they'd also have to go through the Van Allen radiation belts which could also be a concern. Conspiracy theorists have argued that space travel to the moon was impossible because the Van Allen radiation would kill or incapacitate an astronaut who made the trip. In practice, even at the peak of the belts, one could live for several months without receiving a lethal dose.

    Apollo had timed things however to make it accross while radiation was at a minimum. However, if they'd be on such a long trip -- timing will have to be a lot more precise.

    Short of hauling up lead plates, I don't know what they'll do.
    • Re:Is this news? (Score:5, Informative)

      by Cheerio Boy ( 82178 ) on Wednesday August 03, 2005 @01:51PM (#13232216) Homepage Journal
      However, if they'd be on such a long trip -- timing will have to be a lot more precise.

      I didn't understand half the math in The Case for Mars [] but the author explains in detail how the route could be planned to be both low cost and safe from radiation.

      I need to read that again...
    • Short of hauling up lead plates, I don't know what they'll do.

      Space concrete. Lots of it.
    • Re:Is this news? (Score:3, Interesting)

      by demachina ( 71715 )
      This is a really alarmist article but its actually great people are finally get out of the multidecade fixation on LEO and thinking about these things again.

      The first reason you want a moon base is to study, learn to deal with and minimize the radiation exposure.

      "Short of hauling up lead plates, I don't know what they'll do."

      Put the crew compartment inside a water tank, since you are going to need the water anyway.

      Build shields out of lunar regolith since its gravity well is smaller, though you need to have
  • However, the remaining 90% would get the ability to turn invisible, an orange rocky carapace, self-immolation at will, or very stretchy limbs.


  • Sign me up (Score:5, Insightful)

    by Lehk228 ( 705449 ) on Wednesday August 03, 2005 @01:45PM (#13232131) Journal
    I'd be willing to take a 10% risk of cancer later in my life in order to see mars. Hell i'd take a 10% chance of not surviving the trip home.
    • If you die on the way home, you can't use your trip to Mars as a pickup line!
    • by pavon ( 30274 )
      Permanent settlers, while having a significanly shorter life expectancy, would also undergo slightly excelerated evolution :)

      Seriously though, what about the first europeans to the Americas. They were at least as likely to dye from malnutrition during the trip, not to mention all the hardships they faced when they got there. That is what it means to be a pioneer - to take risks and pave the way so others after you can go more safely.
  • by crmartin ( 98227 ) on Wednesday August 03, 2005 @01:45PM (#13232135)
    2.2 Sieverts is 220 rems. that's like 8-10 times previous estimates. And you've got to wonder about quotes like this:

    Others suggest more radical solutions might be needed. "Radiation exposure is certainly one of the major problems facing future interplanetary space travellers," says Murdoch Baxter, founding editor of the Journal of Environmental Radioactivity. "Unless we can develop instantaneous time and space transfer technologies like Dr Who's TARDIS."
  • MMPP (Score:5, Interesting)

    by cryptochrome ( 303529 ) on Wednesday August 03, 2005 @01:46PM (#13232144) Journal
    Wasn't mini-magnetospheric plasma propulsion [] supposed to offer robust shielding, in addition to efficient travel?
  • Oh no! (Score:5, Insightful)

    by nathan s ( 719490 ) on Wednesday August 03, 2005 @01:46PM (#13232150) Homepage
    Let's never leave our little shielded planet because we might get cancer!

    Seriously, I'm sure that there are thousands of people who would line up, despite that 10% chance of a disease that some of them will get anyway. I would.

    Go to Mars, keep working on cancer cure. Everybody wins.:-)
  • by FunWithHeadlines ( 644929 ) on Wednesday August 03, 2005 @01:47PM (#13232155) Homepage
    "A massive spacecraft built on the moon might possibly be constructed so that the shielding would reduce the radiation hazard," he told New Scientist. But even so he reckons that humans will be unable to travel more than 75 million kilometres (47 million miles) on a space mission - about half the distance from the Earth to the Sun. This allowance might get them to Mars or Venus, but not to Jupiter or Saturn."

    So even if they cannot solve the cosmic radiation problem entirely, there is a possibility that could get them safely to Mars and back. Of course first we'd need that Moon base I've been reading about in SF stories written as far back as forever...

  • Exposed to cosmic radiation during a space mission, austronauts are torn apart and reformed atom-by-atom. Soon after they return to Earth, they each manifest fantastic superpowers. Some can stretch their bodies to inhuman lengths; Others can become invisible and create force fields; still others can ignite their bodies into living flame and soar through the air; and an unlucky few's human features are erased - now with the rocky form of a super-strong, invulnerable 'thing'.

    Hope they never make a movie about
  • "Radiation exposure is certainly one of the major problems facing future interplanetary space travellers," says Murdoch Baxter, founding editor of the Journal of Environmental Radioactivity. "Unless we can develop instantaneous time and space transfer technologies like Dr Who's TARDIS." Star Trek's Transporter room. While we're brainstorming on alternate solutions, developing radiation-resistant superhumans who do the interplanetary space exploration for us doesn't sound like a bad idea either.

  • "Cancer deaths accounted for 23 percent of all deaths" according to []
  • Seriously. Send healthy older astronauts. Wouldn't their slower metabolism mean that they may never suffer any ill effects from the radiation?
  • Oh crap. (Score:5, Insightful)

    by BigZaphod ( 12942 ) on Wednesday August 03, 2005 @01:49PM (#13232176) Homepage
    Space is dangerous?!? Wha??!!! Wow.. We better not go there then! RUN AWAY! Someone might die! *gasp* *shock* Horror!!!!!!1111one!

    I think any first travelers to Mars would have far more impressive ways to die than a 10% chance of radiation damage. The ship could explode, they could run out of food, they could hit any of the various bits of rock out there, they could get abducted by the aliens that live on the other side of the moon, they could slip and fall while getting out the shower cracking their skulls open, etc.
  • by TripMaster Monkey ( 862126 ) * on Wednesday August 03, 2005 @01:49PM (#13232184)
    From TFA:
    "Radiation exposure is certainly one of the major problems facing future interplanetary space travellers," says Murdoch Baxter, founding editor of the Journal of Environmental Radioactivity. "Unless we can develop instantaneous time and space transfer technologies like Dr Who's TARDIS."
    Thanks a lot, Murdoch...very helpful. Are you sure you haven't soaked up too many RADs yourself?

    Seriously, though, does anyone know just how much material is needed to block these rays? Specifically, if a space habitat were constructed (along the lines of an O'Neill cylinder, for instance), how many meters of rock would we require on the outer surface to make the place long-term habitable?
  • >>> The study estimated that individual doses would end up being very high, at 2.26 sieverts.

    Interesting. However, that this is 2.26 sieverts for the total mission. Usually, you get nausea, etc as part of the acute radiation syndrome, assuming that you are getting those in a few hours.
  • by RevRigel ( 90335 ) on Wednesday August 03, 2005 @01:50PM (#13232207)
    If they're talking about current chemical propulsion technologies, then yes, they'll be out there for the better part of a year. If we get dig out nuclear propulsion technology that's already been developed, such as NERVA, and other things such as gas core nuclear rockets, it's simple to cut the trip down to weeks while simultaneously packing dozens of tons of extra shielding.
  • Other things that could kill astronauts visiting mars:

    -cosmic space rocks
    -cosmic lack of oxygen
    -cosmic freezing
    -cosmic burning
    -cosmic vacuum
    -cosmic alien species
    -cosmic cowboy neil

    hey! its a dangerous universe!
  • Firstly, we need nuclear power. Kind of a "fight fire with fire" approach.

    For mars habitation, build a base underground?

    For the journey, build the spacecraft out of very, very thick material? Not some exotic material, just a thick layer of rock would suffice, yes?

    use our nuclear generators to create a massive magnetic field around the spacecraft.

    It must be possible to overcome these problems. After all, we are traveling on a spaceship right now, and it's doing a pretty good job of shielding us from radiation.
  • > Unfortunately, New Scientist reports that Astronauts traveling to Mars would be exposed to so much cosmic radiation that 10% would die of cancer.

    So, out of 10 astronauts, one dies of cancer that he or she wouldn't have gotten had she or she stayed at home.

    For each astronaut, there's a 90% chance of suffering no ill effects from the increased radiation exposure. (That is, they'll get to die of a heart attack, stroke, of an injury after a fall, in an auto wreck, or of a cancer they were going to ge

    • Whether it's hostile indigenous personnel, weird diseases, dangerous travel methods, or even lunatic fellow crew members, going to far away new places has always been dangerous. And there have always been explorers willing to risk life & limb (and someone else's money) to do it.

      What's with the penchant for making it safe and sanitary? Those should be long-term engineering goals, not short term requirements for pursuing exploration. If it always had to be safe and comfortable, Lewis & Clark would
  • Just start recruiting chain-smokers and/or people from Memphis, TN into the astronaut program. Provide the smokers with nicotine inhalers for the duration of the mission and all will be well. Their chances of dying prematurely are astronomically greater than your average person, as it is. The latter group already faces 10% increase in the chance of dying just walking outside to get the paper.

    (Hey, I lived there for 3 years and most people would choose to risk terminal cancer than stay)
  • In TFA
    loss of fertility and genetic defects in their children

    They could always get their eggs/sperm sampled and frozen before the trip.
  • don't go swiming in the canals on a full stomach, or pet strange life forms.

    And what ever you do DON'T LET DOVES LOOSE. It could start a War!!

  • ...turns out that you can't even get to the water!

  • by fwice ( 841569 ) on Wednesday August 03, 2005 @01:52PM (#13232241)
    Astronauts traveling to Mars would be exposed to so much radiation that 10% would die of cancer.

    For once I'm glad I have a tinfoil hat!

    (cue rimshot)
  • Just seems like our concept of constructing space ships, and the logistics change. Not that long space travel will not be possible.

    We need methods to get tonnage of materials into space, that's all.

    When that gets solved, we'll get another article on lead poisening and space travel ;-)
  • Yes there is space rad. And it sucks, alot. But I'd like to belive that we have enough common sense to figure out how to bring this to a minimum. I'm preety sure NASA knows about this magical radiation - and took it into account when making their plans to go take a sunday stroll to the moon or mars.

    Besides - the two best sources of technological improvement: war & space travel. Maybe they'll invent the anti-cancer pill finally.
  • He's old...
  • Send off death-row inmates or other criminals. Next thing you know, there'll be a whole colony with weird maps and funky accents.
  • So now, the Space Program will have an interest in Cancer research too (if they're not already doing something). This can only be a good thing. Even if they focus work on materials to protect the astronuts from the cosmic rays, they'll still work on drugs as an adjunct. This can only be a good thing for the rest of the world...

    Tang and the cure for Cancer...what the Space Program is all about!

  • What is the percentage of people here on earth that die from cancer. If its anything close to 10%, then this is not really a risk, more of a fact of life.
  • Cosmic rays from the sun?

    Why don't they just go at night? :)
  • That's quite an improvement, seeing as we all already have a roughly 1 in 7 chance of dying of cancer! []
  • Most slashdoters need SPF 1000 for being outdoors for 5 minutes anyways.
  • The cancer rate in men is nearly 50% and in women it's over 40%. Within 50 years cancer will be controllable like diabetes.

    The trip to Mars radiation doesn't seem insurmountable.
  • Well they should be OK, as long as they use a hands-free device with their cell phones.
  • Really would be nice to use it to save my as from somehting real rather than just keeping the aliens(1) fron listening into my head.

    1) They're not illegal aliens until after they abduct me.
  • by RobertB-DC ( 622190 ) * on Wednesday August 03, 2005 @02:04PM (#13232382) Homepage Journal
    Again, I'm reminded of stories of voyages of discovery from 200 years ago. The crew sailing with Captain James Cook [] actually fared better than most, according to Wikipedia:

    At that point in the voyage, Cook had lost no men to scurvy, a remarkable and unheard-of achievement in 18th century sea-faring. He forced his men to eat such foods as citrus fruits and sauerkraut -- under punishment of flogging if they did not comply -- although no one yet understood why these foods prevented scurvy. Unfortunately, he sailed on for Batavia, the capital of the Dutch East Indies, to put in for repairs. Batavia was known for its outbreaks of malaria, and, before they returned home in 1771, many in Cook's crew would succumb to the disease, including the Tahitian Tupaia, Banks's secretary Herman Spöring, astronomer Charles Green, and the illustrator Sydney Parkinson.

    Would it be that much worse to be afflicted with cancer in the 2000's than with malaria in the 1700s? At least we have morphine now.

    The suggestion that brain ailments might afflict spacefaring explorers strikes a familiar chord as well:

    Cook returned to Hawaii in 1779. On February 14 at Kealakekua Bay, some Hawaiians stole one of Cook's small boats. Normally, as thefts were quite common in Tahiti and the other islands, he would have taken hostages until the stolen articles were returned. However, his stomach ailment and increasingly irrational behaviour led to an altercation with a large crowd of Hawaiians gathered on the beach. In the ensuing skirmish, shots were fired at the Hawaiians and Cook was speared to death.

    Another factor to keep in mind is the motivation of the sailors. For one thing, conditions at home didn't offer much better chance at longevity. But perhaps more importantly, Captain Cook believed in the medicinal value of large quantities of beer []:

    The custom of allowing British seamen the regular use of fermented liquor is an old one. Ale was a standard article of the sea ration as early as the fourteenth century. By the late eighteenth century, beer was considered to be at once a food (a staple beverage and essential part of the sea diet), a luxury (helping to ameliorate the hardship and irregularity of sea life) and a medicine (conducive to health at sea).

    It sounds like we won't be exploring Mars until we have a population of would-be explorers that is 1) worse off here than in space, 2) led by a captain with a penchant for the lash, and 3) drunk off their arse.
    • We try not to send people into situations where they might die any more. Used to be a much more popular concept, but now it only applies to war (and even at that you don't see the presidents and decision makers sending their kids into danger as often)

      This is probably a positive thing. Anyone who thinks we should just risk the 10%, please volunteer your children (or yourselves) now.

      An even bigger problem with this type of situation is that people cannot conceive of a situation until they have lived it.

  • by bigtallmofo ( 695287 ) on Wednesday August 03, 2005 @02:15PM (#13232496)
    Basically this study is saying that with our current technology, it would be difficult to go to Mars or anywhere beyond. That itself wouldn't be so bad if the tone of the article made it sound impossible to do at all.

    With 1960 technology it wouldn't have been possible to go to the moon. But with 1969 technology, it sure was. In 2005, we might lack radiation shielding that makes interplanetary distances hard to traverse without killing you 50 years from now. But in 2015, it might very well be easy to have lightweight material shield you adequately.
  • by Mr. Cancelled ( 572486 ) on Wednesday August 03, 2005 @04:04PM (#13233864)
    Seriously, this is one of the same arguements from those who don't believe we ever visited the moon: The cosmic rays would kill you.

    It's an interesting theory, but also one which must be answered before long term/distance space travel will be possible. Or even short term travel, if the conspiracy theorists are to be believed.
  • One thing this and most other articles fail to mention is that radiation exposure on the Martian surface is about 75% of that in space. The thin Martian atmosphere offers little protection, and when particles get through and strike atoms in the soil they create a scatter of secondary radiation, some of which scatters upward.

    One of NASA's Design Reference Missions to Mars involves a total mission duration of 900 days with a 500 day stay on the surface. This mission would expose the crew to more than their allowable lifetime radiation dosage. Another mission profile involves a 435-day duration. Both of these missions involve a year's round trip travel time, and virtually doom the crew to early cancer deaths after their return to Earth.

    Gaseous Core Nuclear Rockets would make Mars missions truly feasible. For reasons discussed in detail here, [] here [] and here, [] among other places, GCNR rockets would get a mission to Mars and back in 270 days, with 7 months travel time and 60 days on the surface. Additionally, the GCNR rocket would have huge carrying capacity, enough for the craft to carry a foot-thick water shield in a double hull. Such a ship would reduce the crew's total radiation exposure to about 1/5 of the 435-day mission and 1/10th of the 900 day mission. The water layer would also act as a giant passive heat sink, eliminating the need for a complex refrigeration system. It would also be a self-sealing micrometeorite shield -- the outer few inches of water would freeze, and if a micrometeorite punctured the hull the escaping water would refreeze over the hole immediately.

Exceptions prove the rule, and wreck the budget. -- Miller