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Space Science Technology

Clean Nuclear Launches? 838

Posted by michael
from the lead-lined-underwear dept.
AKAImBatman writes "When it comes to launching millions of pounds of material into space, nearly everyone knows about the Orion Project. Blow up a series of nuclear bombs under your dairy-aire and ride the explosion on up. Unfortunately, the Orion spewed out so much radiation that it just wasn't a feasible launch option. If we want commuter trips to space, we're going to have to find another way. Well, it turns out that NASA's been doing quite a bit of research on Gas Core Nuclear Rockets, an ultra-powerful nuclear rocket that puts out almost no radiation. This research has spurred a fascinating new generation of ideas on reaching the cosmos. Could inexpensive cruises to the moon happen within our lifetimes?"
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Clean Nuclear Launches?

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  • Two Words (Score:5, Insightful)

    by Hell O'World (88678) on Tuesday January 13, 2004 @03:32PM (#7964975)
    Space Elevator. Everything else is too dangerous and expensive.
    • Slashdot has posted several articles on how close we are to having strong enough material for this... But isn't part of the space elevator a huge-ass asteroid in orbit?
      • Re:Two Words (Score:5, Interesting)

        by squiggleslash (241428) on Tuesday January 13, 2004 @03:41PM (#7965087) Homepage Journal
        Not necessarily. The space elevator needs equal pull on both sides of the point where it would be at the same distance from Earth as objects in geosynchronous orbit. You can either do that using a counterwieght such as a large asteroid, or by making the elevator exceedingly long, about the same length on either side of that geosync orbit position.

        There's a genuine safety issue with space elevators that ought to mentioned though, which is that if the elevator breaks, the part between Earth and the break point would act as a whip. A few thousand miles probably wouldn't be a big issue, but the closer to the end the cable breaks, the bigger, exponentially, the whiplash. A shockwave that destroys significant amounts of life on Earth isn't impossible.

        • by *weasel (174362) on Tuesday January 13, 2004 @03:44PM (#7965111)
          now that's fresh fodder for a hollywood disaster film if I've ever heard it.
        • Re:Two Words (Score:5, Informative)

          by epiphani (254981) <epiphani&dal,net> on Tuesday January 13, 2004 @03:50PM (#7965176)
          I hate when I see this arguement.

          Look at some of the more recent space elevator designs [www.isr.us].

          Basically, the elevator would be made out of a ribbon so light and with such a surface area that it would fall to the earth like a peice of paper. At least that section of the ribbon that doesnt burn up while entering the atmosphere.

          A space elevator isnt like the ones you read about in Kim Stanley Robinsons Mars trilogy.

        • by Ungrounded Lightning (62228) on Tuesday January 13, 2004 @04:13PM (#7965381) Journal
          The space elevator needs equal pull on both sides of the point where it would be at the same distance from Earth as objects in geosynchronous orbit. You can either do that using a counterwieght such as a large asteroid, or by making the elevator exceedingly long, about the same length on either side of that geosync orbit position.

          Admittedly, the basic ground-to-counterweight-above-sync-orbit design has great potential. But there are other designs with less cost, extreme materials, and risk.

          For instance: A section of cable in low orbit, spinning end-over-end so that each end periodically dips into the stratosphere at approximately the average local wind speed. Fly up to it, hook on as it goes by, and get lifted into orbit. Balance the momentum by bringing back a payload of space-mined material on the other end.

          Build it so that if the orbit decays it will break up on reentry rather than crashing, keeping its own mass low enough that it won't create another Cretaceous event by spreading tons of red-hot debris throught the upper atmosphere if it comes in. (But if you get your spin right you can design it so that it tends to be pushed UP if the active guidance fails.)

          Use a near-circular orbit if you want to lift a lot of payloads to near orbit (where you can use slower engines - like ion or light-sail - to achieve high orbit or escape), or an eliptical orbit for fewer payloads to a higher initial launch.

          Lots of ways to do the active guidance:
          - Control the spin with currents through the cable to electron guns and collectors at the ends working against the earth's mag field.
          - Small attached light sails - For orbital elements, spin, attitude, AND killing vibrations.
          - Ion thrusters ditto - and you can collect reaction mass each time an end dips into the atmosphere.
          - Control, solar power plant, etc. at the center, which never enters the atmosphere. (Elevator/cable-crawler to get there from the ends.)

          Lots of other systems are possible, too.
        • Re:Two Words (Score:3, Interesting)

          by 2short (466733)

          "Exceedingly long" is a bit of an understatement. The length you're talking about (with just more elevator for a counterweight) is roughly 12 times the earths radius. Even with a counterweight system, the distance to geosyncronous is almost 6 earth radii. So, aproximately, you need a cable that completely encircles the earth when laid flat, and is strong enough to support its own weight when hung on end. I don't see that kind of strength-to-weight ratio being produced any time in the near future. And e
          • Re:Two Words (Score:3, Interesting)

            by Quaelin PoD (551815) *

            I don't see that kind of strength-to-weight ratio being produced any time in the near future.

            Pure carbon nanotubes have the required strength-to-weight ratio. The only question is how long before we can develop a composite that binds CNTs together into a material that retains enough of the strength of pure CNTs. Steady progress is being made. Keep an eye on LiftWatch.org [liftwatch.org] for regular updates on this and related techs.

      • Re:Two Words (Score:3, Interesting)

        by jovlinger (55075)
        hrm. I seem to recall that space elevators needed tensile strength/weight ratios that could basically only be made monomol. And that ringworld required entirely new physics to work.

        However, a space elevator on mars might be more feasible, (the moon would be the first option, but it spins too slowly for geosynch to work).

        I think Charles Sheffield is probably closer to a workable idea.

        For example, not an elevator, but stairs: big rotating disk satelites in orbit (where plane of rotation is along orbit and
    • Re:Two Words (Score:3, Insightful)

      by nizo (81281)
      Umm, what happens if it breaks somewhere high up? I can't imagine I would want to be anywhere near where the "stalk" came crashing down. Don't get me wrong, I am not real keen on nuclear filled rockets that could explode on or soon after launch either.
      • Re:Two Words (Score:5, Informative)

        by Baron_Yam (643147) on Tuesday January 13, 2004 @03:43PM (#7965107)
        You should read up on the concept;
        • The ribbon would end up fluttering down and wouldn't be dangerous at all
        • The counterweight would fly off into space
        • Any load ON the ribbon would be a different matter, but hey, the space shuttles fell without causing planet-wide destruction.
        Also, the base of the ribbon would probably be a floating platform in the middle of an ocean, so any falling load would be extremely unlikely to hit land.
    • Re:Two Words (Score:5, Insightful)

      by IWorkForMorons (679120) on Tuesday January 13, 2004 @03:40PM (#7965074) Journal
      Ok...I'll give you that. To get into space, a space elevator is probably a better idea. Two reason to continue developing nuclear engines:

      1) We don't have space elevators. Simple as that. Until the day they are reality, we need something better then conventional rockets.

      2) Once in space, either through the use of these rockets or a space elevator, these would be extremely useful for getting around the solar system, or at least roaming our backyard (the moon) or visiting next door (Mars).

      IANARS (rocket scientist), but I enjoy learning about developments in space tech. The nuclear engine, while different versions having been developed and tested decades ago, still looks to be the next best thing in space travel.
      • Re:Two Words (Score:5, Insightful)

        by Phekko (619272) on Tuesday January 13, 2004 @03:57PM (#7965231)
        You forgot

        3) How are we supposed to get the space elevator up in the first place?
        • by Xzzy (111297) <sether@tru7hMONET.org minus painter> on Tuesday January 13, 2004 @04:19PM (#7965441) Homepage
          just tie some twine to the tail of the space shuttle as it goes up, of course.

          Then you tie a slightly heavier cable to the twine, and have the guys on the space shuttle start tugging it up.

          Once that's up, tie an even heavier cable to the second cable.. and start tugging. Repeat until you have a properly sized cable in place for your elevator.

          I was gonna pitch this idea to NASA a few years ago but they never called me back. ;(
      • Re:Two Words (Score:3, Interesting)

        by isomeme (177414)
        Also, building the space elevator involves moving insane amounts of mass around, both up from earth and in from elsewhere in the solar system (e.g., Luna or the asteroids). The space elevator would be several orders of magnitude more massive than the combined total of everything ever sent into space to date, and that's even if you count each Shuttle launch separately. There's no reasonable way to build a space elevator without nuclear propulsion.
      • Re:Two Words (Score:5, Interesting)

        by MikShapi (681808) on Tuesday January 13, 2004 @04:21PM (#7965468) Journal
        Actually, a SE makes a significantly better, safer and cheaper inter-solar-system-transportaion-system than dirty bombs. It's not just a tool to escape orbit - it can take us to other planets. That's what's so genious about the idea.

        There are two reasons for making it 91000km long when all you technically need is 35000km.

        One: because you need a very large and unfeasible mass at the top if you want to balance 35000km of cable hanging below GEO with a weight located, say, 1 meter above it. You need a significantly smaller weight at the top if you want to balance it at 91000km.

        Two: (which brings us back to our point of discussion) If you go as far as 91000km, you can slingshot payloads as far as jupiter and its moons [www.isr.us]. If you build even higher, at 140000km you can get as far as pluto.

        Of course, the first thing you'd want to send to your destination is a pre-fabricated and spooled SE to deploy there, so you can send stuff back...
    • Re:Two Words (Score:5, Insightful)

      by Tackhead (54550) on Tuesday January 13, 2004 @03:47PM (#7965143)
      > Space Elevator. Everything else is too dangerous and expensive.

      Two more words for you: Suspension bridge.

      When you can build a 40,000-millimeter suspension bridge out of carbon nanotubes and cross the river near the campus materials lab building, then you can start fantasizing about a 40,000-kilometer space elevator.

      Until then, NERVA is the only way to go. Everything else is still at the research stage.

      • Re:Two Words (Score:4, Informative)

        by MikShapi (681808) on Tuesday January 13, 2004 @04:40PM (#7965680) Journal
        I think you need to have a look at Liftwatch [liftwatch.org]. There are a lot of announcements such [liftwatch.org] as [liftwatch.org] these [liftwatch.org]. There are nanotube advancements almost every month, and a whole bunch of universities and corporations worldwide are throwing rather large sums at putting it under heavy research. A 1km cable with 2% CN loading was already constructed a while ago. Smaller stretches were already made with 5% loading at the time the NIAC phase II was written, and was mentioned in said paper.

        You neither need to grow a 35000km buckytube, nor do you need to reach a 100% CN-loaded ribbon.
        Composites will be made with a higher and higher CN loading, and once a certain percentage is reached (feel free to check the NIAC 2 paper [spaceelevator.com] which draws this line quite clearly), you'll have elevator-worthy material. At the rate CN loading in composites has been increasing in the past decade or so, we should [hopefully] have elevator-worthy material in about 2 years.

        Cheers.
  • by magarity (164372)
    We should still build a secret Orion and keep it handy in case of alien invasion.
  • by CompWerks (684874) on Tuesday January 13, 2004 @03:33PM (#7964986)
    Run a wire to the International Space Station and use straws glued to the sides of the rocket to guide them.

    Now, I'm no rocket scientist, but I think you get the idea..

  • Space Elevator (Score:2, Redundant)

    by cflorio (604840)
    I still think the Space Elevator [www.isr.us] will be the ticket for inexpensive space launches.
    • Re:Space Elevator (Score:5, Insightful)

      by mark-t (151149) <markt@@@lynx...bc...ca> on Tuesday January 13, 2004 @03:44PM (#7965117) Journal
      You'd like to think so...

      But unfortunately, the space elevator will be so obscenely expensive in terms of resources and labour to get going in the first place that though amortized over a large number of launches, the cost would indeed be low... they probably won't be willing to wait that long to recover their costs, so launches that way would be even more expensive than the methods we use currently.

  • by Deltan (217782) on Tuesday January 13, 2004 @03:34PM (#7965008)
    ..."almost no radiation"...

    Call me back when there is none.
    • by Anonymous Coward on Tuesday January 13, 2004 @03:39PM (#7965059)
      Call me back when there is none.

      Quick, someone ban the sun.

      And stop people from living in Denver or flying on planes or going skiing in the mountains.

      And let's not forget xray machines, cathode ray tubes (TVs and computer monitors to you non-engineers).

      And what about that deadly substance known as "granite" that releases radioactive radon?

    • by Chris Burke (6130) on Tuesday January 13, 2004 @03:41PM (#7965083) Homepage
      You are being bombared with deadly radiation right now! Coming from the ground, objects in your home, and worst, from mankind's eternal nemesis, the Sun itself. Please flee your home screaming and head for your nearest all-lead fallout shelter!

      We'll call you out when it's safe.
  • Public Perception (Score:5, Insightful)

    by Anonymous Coward on Tuesday January 13, 2004 @03:35PM (#7965016)
    One of the biggest problems with anything Nulcear, be it power, subs, or rockets, there is a very negative public perception. You can tell people that it is safe all you want but there will always be that paranoia. It doesn't help that people don't neccesarily trust the government.
    • Re:Public Perception (Score:4, Interesting)

      by AKAImBatman (238306) <akaimbatman@[ ]il.com ['gma' in gap]> on Tuesday January 13, 2004 @03:48PM (#7965160) Homepage Journal
      Ah, but that's the point of stories like this. Trying to explain to the public that *managed* dangers can bring tremendous benefits.
  • by smoondog (85133)
    I'm not worried about the clean launches. What I'm worried about is the very dirty explosions (UF4 all over the place). I agree with the previous poster on spending money on the space elevator. Lets skip the flying dirty bombs.

    -Sean
  • by Anonymous Coward on Tuesday January 13, 2004 @03:35PM (#7965023)
    I think it's great that the we are still seeing innovation in regards to propulsion for space-bound vehicles. I'm especially excited about the new concepts used in the Vostok [videocosmos.com] booster-like series that the Russian space agency is evaluating.

    We're definately a long way from the V2 when some simple hydrogen would be ignited, and then Bob would be your uncle.

    Radiation can be beneficial and should not be feared. Of course there will be some potential for accidents and some minor radiactive pollution, but it's all worth it in the case of scientific progress. We don't have clean water or clean air, and you don't city inhabitants rioting, or do you?

  • hrm.... (Score:5, Funny)

    by xao gypsie (641755) on Tuesday January 13, 2004 @03:37PM (#7965037)
    on Gas Core Nuclear Rockets
    those have been around for years, and i have been fortunate enough to work with them for much of my life. they are called bean burritos. there is more explosive energy in one of those bad boys than most realize, especially when the chemistry behind the force is just right...granted, the fallout is pretty terrible too...
  • by DaRat (678130) * on Tuesday January 13, 2004 @03:37PM (#7965040)

    A few years back, I remember there being some amazingly loud protests from some anti-nuclear power folks about the dangers of a deep space probe going up with a nuclear power source. Those folks were worried about the danger if the rocket blew up on the pad or the 1 in 100,000 or so chance the probe would hit the earth on one of its acceleration orbits.

    Just imagine how happy these folks will be with a nuclear powered rocket, even if the scientific community claims that they are safe. After all, it's nuclear related, so it's gotta be bad!! (tongue firmly in cheek)

    • by mcc (14761) <amcclure@purdue.edu> on Tuesday January 13, 2004 @04:19PM (#7965445) Homepage
      What the protesters didn't tell you--probably because they couldn't be bothered enough to research they'd know this-- is that (1) we'd been putting up reactors on spacecrafts for years and years and (2) the reactor was one of the most mind-bogglingly safe imaginable, if the entire reactor was blown up or disentigrated in the atmosphere the radioactive material would still be able to hold together well enough that at worst it would split together into a couple of chunks so solid you could pick them up and hold them...

      My suspicion is that Nuclear technology will get nowhere in the United States until people stop calling it that, due to the huge political movement to make sure no one uses anything with "nuclear" in the name, regardless of the safety, degree of research, or degree of oversight. I'd propose scientists start using some other word, like "happytronic", but this would probably be seen through as "hollow PR from the nuclear industry". (That's another thing. People promoting nuclear energy are often derided as "Nuclear Industry Shills", but people attacking it are never successfully labelled as "Coal Industry Shills", despite the fact that's who they're primarily helping. How is this?)

      This is the primary promise Fusion offers IMHO-- because oh, it isn't nuclear, it's "Fusion", right? Which means people will actually use it.

      Perhaps we should start researching some kind of "hybrid" technique, which would allow the creation of reactors that can be claimed to be "fusion" although they're actually just fission reactors with some kind of technique involved that has something vaguely to do with fusion.
      • by eth1 (94901) on Tuesday January 13, 2004 @05:29PM (#7966325)
        How about Inverse Fusile Energy Extraction? :p Or Exothermic Matter Decomposition... or Half-Life Accellotron?
      • i wouldn't say we have a problem with nuclear so much as a problem with non-military nuclear. and i have a feeling it's because we're the only ones who've actually used nukes against anybody -- we've got this stigma, this association between 'nuclear' and 'bomb'. can't be used for anything else now. coal (etc.) industries are more than happy to play off that fear, but i think the public fear came first. it can't have helped that we liked to scare ourselves with nuclear mutant monster movies ...

        on the other side of the pond, you'll find countries like france who have quite the nuclear arsenal as well (as i recall, france has more of a nuclear arsenal than china, and is third or fourth in the world?) but also get the vast majority (74% or so? that was in my high-school days) of their power from nuclear plants. and they're not worried about it. it was also france that had, what was it called ... super-phoenix? to burn the waste from normal nuclear plants to produce extra power from it, along with a different kind of waste, i believe. i do remember the local villagers didn't care for that project too much (what with shipping nuclear waste into the town on a regular basis!) in any case, they don't really mind nuclear power, though they would (from what i can tell) slightly prefer hydro-electric power.

        germany, on the other hand, is heading to dismantle and sell its nuclear reactors in favor of ... something else. so long as they don't go back to coal, eh, whatever. seems to me the north shores of germany would be an excellent place for hydro-electric power.

        it is very much a problem of perception. just don't use the words 'radiation', 'emission', 'atomic', 'split', 'neutron', 'proton', 'electron', 'blast', 'coil', ... in the new name. wait, are we afraid of anything technical-sounding? "super-efficient steam engine" maybe?
      • What the protesters didn't tell you--probably because they couldn't be bothered enough to research they'd know this-- is that (1) we'd been putting up reactors on spacecrafts for years and years and (2) the reactor was one of the most mind-bogglingly safe imaginable, if the entire reactor was blown up or disentigrated in the atmosphere the radioactive material would still be able to hold together well enough that at worst it would split together into a couple of chunks so solid you could pick them up and ho
  • Within our lifetime? (Score:5, Interesting)

    by addie (470476) on Tuesday January 13, 2004 @03:37PM (#7965042)
    Could inexpensive cruises to the moon happen within our lifetimes?

    I highly doubt it. As the last twenty years have shown, it's not the level of technology that determines how easily we get into space, it's the cost. And concepts such as these, while interesting to think about and develop, are ultimately going to take that many more decades to become proven.

    Add to all this that the public would need a near-100% safety record in order to buy into a space tourism industry, and we're looking at more decades added onto the R&D and testing.

    However, this kind of engine if developed properly COULD lower costs for putting satellites in orbit. So what's our benefit in the end? Lower satellite TV, telephone, and internet costs perhaps... But that's being optomistic.

    But the design itself? Neat.
  • Hmmm (Score:3, Funny)

    by odano (735445) on Tuesday January 13, 2004 @03:38PM (#7965046)
    How many years are we talking about? The lease on my land on the moon is running out, and I need to know how soon I should renew.
  • by Anonymous Coward on Tuesday January 13, 2004 @03:38PM (#7965050)
    (article text, minus pictures)

    Opening the Next Frontier
    by Anthony Tate

    Part 1: The Frontier Spirit

    America loves its legends. George Washington in Valley Forge. The Wild West. World War II. The Man on the Moon.

    But lately, it seems the legends have stopped.

    Sure, we have the Internet to play with now, and computers are changing the world in ways we can scarcely grasp as of yet. The Soviet Union is no more, and despite our current travails with terrorism, a certain comfortable familiarity has us in its grip.

    Where is the next legend? Where is the next frontier? Or are we just going to go comfortably off into retirement?

    If the 'entertainments' of the kids these days are any indication, no way.

    Extreme sports, fun little things like 'base jumping' and other diversions indicate that the next generation of Americans are harkening back to their roots in a big way. America is ready for the next challenge, refreshed, revitalized, and shaking off old fears and inhibitions.

    But what could have caused our recent doldrums?

    Why have we not gone back to deep space, that logical 'Final Frontier,' for so many years after Apollo? I believe it was a confluence of several factors, most of which have now passed, that caused us to huddle close to the bosom of Mother Earth for these past decades.

    Part 2: What went wrong.

    To be blunt, it was the 70's.

    After the turbulent change of the 60's, the 70's were just a hard time for America. The Cold War dragged on and on, no end in sight. Vietnam was a horrible, bloody mess, deeply misunderstood to this day, and bitterly divisive even in the aftermath. Watergate destroyed the faith of millions in their own government. The Oil Embargo shocked the economy as well, causing the nightmarish condition of 'stagflation.' Cultural upheaval became the norm as gains in civil rights were cemented into place.

    With that litany of bad news, there is little wonder that the public lost interest in space. When you are scared for your job, your children, and whether or not your paycheck next year will still cover the rent, idealism and exploration goes out the window.

    Also, lets be honest, landing on the Moon in the 1960's was an incredible feat. That entire rocket, the whole plan, was designed, built, and flown using less computing power than you have in your PC. Genius level effort was used to make that program possible, and the chance of disaster was perilously high, even by the comparatively relaxed standards of the day. In other words, Saturn was ahead of its time, by many years.

    If it wasn't for the Cold War imperative to beat the Soviets, we'd probably be looking to go to the Moon right about now, all things considered.

    Add in the fact that science itself was throwing up massive roadblocks, and there is little surprise to be had from the seeming 'retreat from space.' The rocket fuel used in the Saturn V moon rocket at launch was BETTER than the rocket fuel used to launch the Space Shuttle today. Why is that? Well, it's simple: The chemical fuels used in the Saturn V are among the best fuels that chemistry allows. Science is remarkably inflexible: unlike in the movies we can't just 'whip up' better rocket fuels. Chemistry is pretty stubborn that way.

    So, exploring further in space was not important to the country while we had other problems to deal with, and making rockets better than the SaturnV was pretty much impossible.

    So, NASA went sideways for a while. The Space Shuttle is a remarkable system, but it is at its core a compromise. So while it is good at many things, it is great at nothing. But nonetheless, the Space Shuttle kept America in space, and slowly we were building momentum to move forward once again away from the Earth.

    Then Challenger blew up (and now we've lost Columbia and her crew as well).

    Now, to the doughty folks who made Apollo fly, that disaster would have been a learning experience, and development would have continue
  • Launches? (Score:5, Informative)

    by znu (31198) <znu.public@gmail.com> on Tuesday January 13, 2004 @03:39PM (#7965056)
    My understanding is that the clean nuclear propulsion systems presently under serious consideration don't provide a high enough thrust/weight ratio to actually lift a spacecraft off the surface of the Earth. Rather, their primary use would be for entirely space-born craft, which would be assembled in orbit and zip around the solar system without actually ever touching down anywhere.
  • by sielwolf (246764) * on Tuesday January 13, 2004 @03:39PM (#7965061) Homepage Journal
    From dictionary.com:

    2 entries found for derriere.
    derriere also derriere ( P ) Pronunciation Key (dr-ar)
    n.

    The buttocks; the rear.


    Also:

    No entry found for dairy-aire [tripoli.org].

    It's like the difference between a segway and a segue. One is a normal word used in English, the other is an amalgam coined for some other purpose.

  • It will never happen (Score:5, Interesting)

    by Tassach (137772) on Tuesday January 13, 2004 @03:40PM (#7965073)
    Most people go batshit whenever they hear the N-word. That's why NUCLEAR Magnetic Resonance Imaging had to lose the N before it could go mainstream. NMRI became MRI for PR purposes, not because the technology changed.

    The environmental whackos go nuts (and let slip the lawyers of war) when you launch a totally sealed reactor, can you imagine what they would do if you wanted to launch something that *gasp* released radioactive gasses into the atmosphere?

  • by j_dot_bomb (560211) on Tuesday January 13, 2004 @03:44PM (#7965120)
    To prevent any sealed radio active capsule from possibly breaking on impact with the ground a malfunctioning rocket will have a 50Meg hydrogen bomb on it to destroy all the pieces in the air
  • by daemous (43293) on Tuesday January 13, 2004 @03:45PM (#7965130)
    The Project Orion guys believed they could make
    the explosions clean and as small as they wanted.
    This scared the shit out of them. They
    puposefully did not pursue that line of
    development for fear of weapons applications.
    • My bull meter just pegged.

      What the Orion researches choose to research or not research has no effect on what other people choose to research and not research.
    • The Project Orion guys believed they could make the explosions clean and as small as they wanted. This scared the shit out of them. They puposefully did not pursue that line of development for fear of weapons applications.

      I call bullshit.

      Source, please. Some relevant links would be nice. If you turn out to be right, I withdraw my bullshit call, but otherwise it stands. I don't recall ever reading anything like this.

  • by Kgreene (606578) on Tuesday January 13, 2004 @03:47PM (#7965144)
    ..."almost no radiation"...

    Drat, it seems to be getting harder and harder to realize my life long ambition of being exposed to massive quantities of harmful radition that will be the key to unlocking my secret mutant powers.
  • Who knew (Score:5, Funny)

    by GoodNicsTken (688415) on Tuesday January 13, 2004 @03:49PM (#7965165)
    Magnetoplasmadynamic was actually a word? And why didn't Piccard ever use it?

    VASIMR (Variable Specific Impulse magnetoplasmadynamic Rocket)- And I though telecom had too many acrynoms.
  • by DerekLyons (302214) <fairwater@nosPam.gmail.com> on Tuesday January 13, 2004 @03:49PM (#7965175) Homepage
    A gas core nuclear reactor has a high ISP (meaning it's very efficient), but it does not have a particularly high thrust. That means it's great for cruising and orbital work, but it's not a launch engine like Orion could be.
  • Well (Score:5, Insightful)

    by cubicledrone (681598) on Tuesday January 13, 2004 @03:57PM (#7965230)
    Could inexpensive cruises to the moon happen within our lifetimes?"

    No.

    See, here's the problem:

    Nothing is permitted any more without a "business case" being made for it. No document, no invention, no idea, no presentation is countenanced unless it has 20% annual growth and the accountants and the management committee sign off on it.

    Since it is impossible to get a bureaucracy to sign off on anything, nothing is permitted at all.

    Small businesses and entrepreneurs are starved for capital. Large businesses and management committees have substantial capital, but refuse to invest it. Therefore, there is no capital; or, if there is, it is usually totally inadequate.

    Middle management has a perfect series of questions for ideas like this. There is nothing in the world easier than criticizing an idea. Questions like "what do we need that for?" and "yeah, but how do you know it will work?" or "how can you be sure that will sell?" These questions are asked as if an answer is expected. The questions are followed by the comments: "It'll never work," and "sounds expensive" and "why can't we just use $OTHER_IDEA?"

    But no answer is expected. The people asking the questions simply want to see how well the "idea person" can ad lib and how many bullshit one-liners and jokes they can reply with. After the middle managers have been entertained, a cocktail party laugh will circle the room, and the idea person will be escorted out of the building and into obscurity as the five-foot-wide-asses return to their bean salads.

    As long as this continues, the rate of invention and "innovation" will be reduced to unmeasurably small levels. No vision, idea or invention can surmount well-funded cynicism. Brilliant, well-educated people's minds are being wasted because they report to lying, cheat fuck, greed-driven managers.

    Middle management routinely turns its back on paying customers and competition-less markets. How the fuck are they ever going to accept a new "unproven" idea?

    They won't.
  • by payndz (589033) on Tuesday January 13, 2004 @04:06PM (#7965316)
    "Ra-di-a-tion. Yes, indeed. You hear the most outrageous lies about it. Half-baked goggle-box do-gooders telling everybody it's bad for you. Pernicious nonsense! Everybody could stand a hundred chest X-rays a year. They ought to have them, too."

    Besides, nobody's going to be sending a nuclear rocket into orbit anywhere near me, so I don't mind. Let the Floridians suck it up! They're already addled from all that solar radiation beating down on their pates and overheating their brains - a bit more won't make much difference...

  • by John Jorsett (171560) on Tuesday January 13, 2004 @04:09PM (#7965342)
    I'm guessing that telling some of the more extreme environmentalist elements that your launch puts out "almost no radiation" isn't going to hack it as far as they're concerned. 1 microrad/hr above background will be reason enough to predict apocalyptic nightmares of mass cancers, food contamination, mutations, dropsy, genital warts, and flatulence. They're essentially anti-technology and will use any excuse to oppose it. Frankly, I'm surprised I can still buy a radium-dial wristwatch.
  • by Barlo_Mung_42 (411228) on Tuesday January 13, 2004 @04:10PM (#7965347) Homepage
    "Could inexpensive cruises to the moon happen within our lifetimes?"

    My hope is that advances in medicine will extend my life to 150+ years so I can see more of these things come to pass.

  • by Ancil (622971) on Tuesday January 13, 2004 @04:29PM (#7965544)

    This called for a 40-million-ton spacecraft to be powered by the sequential release of ten million bombs.

    Orion, they argued, was simple, capacious, and above all affordable.

    I would love to see the more expensive option. Even paying "only" $1 million per nuclear bomb, that works out to $10,000,000,000,000.00 (ten trillion). 40-million-ton spacecraft not included, some assembly required.
  • by kurtkilgor (99389) on Tuesday January 13, 2004 @06:34PM (#7967041)
    A lot of people claim that the reason why the US doesn't use nuclear power everywhere is because of environmentalist whackos. This is not true. The reason is economics.

    Back in the 50's when nuclear power was first proposed, people talked about having electricity too cheap to meter. The thing they did not consider is that a nuclear power plant costs much more to build than a coal/oil/natural gas plant. I want to make sure everyone understands why.

    First of all, the radiation given off by fission destroys inorganic materials just as happily as it destroys human tissue. Very high quality metal must be used in all parts of the reactor to prevent degradation and to prevent it from becoming highly radioactive. This is even more of a problem in fusion reactors which have a much higher flow of neutrons, and in those, the only solution will be to replace the pieces every so often.

    Second, the plant must be extremely highly reliable. One reason for this is draconian public safety regulations. However you have to keep in mind that even an accident that is contained within the plant and poses no risk to the public (a la Three Mile Island) can still destroy the reactor and put the plant out of commission.

    This is true because of a property of the nuclear chain reaction. Dropping all of the control rods (scramming) does not instantly shut down the reaction in the way that dousing a coal fire would extinguish it. The reactor will continue to produce heat for around an hour after it is shut down. This means that it must be cooled for that hour, otherwise it will melt and flood the building with radioactive chemicals. The Chernobyl accident was caused by an attempt to test what happens if the cooling system is disabled.

    So the system has to be very highly redundant, in part to protect the public, but mostly to protect the plant.

    The last problem is that if the coolant is radioactive, you can't just call in a plumber to fix the leak as you might in a coal plant. See the movie K-19 Widowmaker for the effects of radioactive coolant on humans. You better make damn sure that system doesn't leak in the first place.

    So the plants are expensive. This means you want economy of scale and build one large plant instead of many small ones. This means you don't want to build these plants in the Midwest where that much power just isn't useful. You want to build them near population centers. That explains why there is no nuclear power in sparsely populated places.

    The other thing is that even though uranium is much cheaper than coal per joule (because you need so much less of it), the cost of the nuclear plant makes the whole process expensive enough that it has to compete with coal for the market. This means that in places where coal is cheap (as in the United States) building nuclear plants is only sensible up to a point. As the nuclear plants drive down demand for coal, the coal gets cheaper, so there is a natural feedback mechanism.

    In the United States, we are a little bit below the optimal balance. We could economically build more nuclear plants but not that many. This difference is in part accounted for by the public perception of nuclear power.

    It is also accounted for by the fact that it takes ten years to build a nuclear power plant, so if you have an energy crisis NOW, building a nuclear power plant is no good. California had to go with building natural gas power plants after their energy crisis because they are cheap and fast to build. Natural gas is more expensive but that's life.

    Now it should be clear why France and Japan, two countries that use nuclear power for most of their needs, are able to do so while the US cannot. It has nothing to do with progressive governments or the lack of environmentalists. It is simply that France and Japan are small, densely populated countries (compared to the US) that have expensive coal (compared to the US). So they have a lot of nuclear plants (compared to the US).

    I hope that explains a few things. Now as
  • by Guppy06 (410832) on Tuesday January 13, 2004 @11:24PM (#7969783)
    Everybody knows that the environmental folks would pitch a fit if we tried to launch a fission-based spacecraft. But they already hate President Bush as it is, so he could include a proposal for a new fission-based shuttle replacement tomorrow and it won't get them any more angry at him than they are now (I mean, is it possible?).

    And President Bush could even help handle crowd control at the launch site as well! Let's say we're launching from Cape Canaveral. During that week, Bush flies off to... say... Amundsen-Scott [nsf.gov], muttering phrases like "oil exploration," "WTO" and "nukuler." Maybe suggest he's going to do something that will kill off the ultra-rare Antarctic Dodo. Those myopic protesters that don't die of an instant embolism upon hearing of it will then take off after him, leaving the Cape nearly deserted for lift-off.
  • by njh (24312) on Tuesday January 13, 2004 @11:26PM (#7969803) Homepage
    As far as I can see the glass is supposed to not absorb the 80GW of light, yet the hydrogen is. Is the author claiming that silca glass absorbs less photons than hydrogen? If it absorbed only 0.01% of the total photons it would still get 8MW of heat, which is going to be quite hard to keep cool. For comparison, the optics used in cameras absorb 0.1% of the incoming photons.

    On the other hand, hydrogen doesn't strike me as particularly absorbent. I thought it was mostly transparent except for a few frequencies (the hydrogen bands). As the gas reactor is acting as a purely blackbody radiator it's going to emit in a classical SB distribution, which will mean that most photons are going to just bounce around until they get absorbed by the mirror or glass.

    So the obvious problem to me (and let's face it, I'm not a rocket scientist..) is that you have an 'impedance mismatch' between your energy source and your energy sink.

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