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Space Science Technology

Workable Fusion Starship Proposed 260

Posted by Soulskill from the for-sufficiently-difficult-values-of-workable dept.
Adam Korbitz writes "A former colleague of Edward Teller — father of the hydrogen bomb — has published a new paper proposing a design for what could be the first practical fusion-powered spacecraft (PDF). As described at Centauri Dreams, the design has certain similarities to MagOrion, a 1990s-era proposal for a nuclear-powered spaceship with a magnetic sail and propelled by small-yield fission devices. The proposal's author also has links to the British Interplanetary Society's Project Daedalus, a 1970s proposal for an unmanned fusion-powered interstellar probe designed to reach 12% of the speed of light on its way to Barnard's Star."
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Workable Fusion Starship Proposed More

Workable Fusion Starship Proposed

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  • Oxymoron? (Score:2, Insightful)

    by gzipped_tar ( 1151931 )

    Workable Fusion Starship Proposed

    If it's only a proposal, how do we know whether it is "workable" or not?

    • Re:Oxymoron? (Score:5, Informative)

      by getuid() ( 1305889 ) on Sunday February 01, 2009 @11:51AM (#26684543)
      If what you are proposing relies on technology already in use, or which could very likely be made usable during the next few years (i.e. technology which's basic scientific implications we understand, but just need a little time to figure some "engineering details"), then it's workable. If not, then most probably it's not.

    • Workable Fusion Starship Proposed

      Workable = WORKing + DeniABLE

  • Comment removed based on user account deletion

    • Re: (Score:3, Insightful)

      by wjh31 ( 1372867 )
      what with how sparse the ISM is, i cant personally see that that would be workable

      • Re:Ramscoop design? (Score:5, Informative)

        by geckipede ( 1261408 ) on Sunday February 01, 2009 @12:02PM (#26684621)
        Actually it's too dense. At high speeds (significant fractions of lightspeed) a magnetic scoop acts like a very effective braking system in interstellar gas. A Bussard type ramscoop rocket could only be expected to reach about 0.12c even with highly efficient engines.

        • Re:Ramscoop design? (Score:4, Funny)

          by wjh31 ( 1372867 ) on Sunday February 01, 2009 @12:08PM (#26684655) Homepage
          ah yes, it would have helped if i had read the ramscoop wiki rather than reading the name and guessing what it meant

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          Really? Could a magnetic scoop then be used for braking on a ship that used a different type of propulsion? Because more than half your propellant on an interstellar journey is required due to the need for braking when you get to your destination.

          • Re:Ramscoop design? (Score:5, Interesting)

            by geckipede ( 1261408 ) on Sunday February 01, 2009 @04:20PM (#26686609)
            Yes, absolutely. It has been proposed as a part of laser-boosted lightsail missions to other stars. A full sized collector scoop would work in interstellar gas, but you only need a relatively small magnet if you are plowing through solar wind (er... stellar wind, since it isn't Sol?). A superconducting cable spooled out of a probe and given a current could be used as a braking system to decelerate at a destination star. I recall seeing an estimate somewhere that the peak deceleration of a relativistic craft like this hitting the heliopause would be about 12g, not comfortable but very effective and cheap way to slow down. Magnetic sails have also been proposed as a way to accelerate in the first place, but in that case you are limited to speeds less than that of the solar wind itself, so it is more suited to in-system missions.

        • Re: (Score:3, Funny)

          by CarpetShark ( 865376 )

          A Bussard type ramscoop rocket could only be expected to reach about 0.12c even with highly efficient engines.

          Only 0.12c? Man, those things depreciate so fast.

    • Re: (Score:3, Funny)

      by Anonymous Coward

      I have designed a spaceship that uses a scoop to collect amazon affiliate codes.

      It will be able to reach Barnards star in a matter of hours.

  • from the article.. (Score:5, Funny)

    by Silm ( 1135973 ) on Sunday February 01, 2009 @11:36AM (#26684455)

    a deuterium fusion bomb propulsion system is proposed where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegampere proton beam,

    that has to be right up there with back to the future. I mean, it has a frickin' gigavolt-multimegampere proton beam

    • Doc Brown says:
          "JIGAvolt it's JIGAvolt!"

    • It's even scarier. When you do the math this thing puts out petawatts!

    • Re: (Score:2, Funny)

      by jimbo2150 ( 1396459 )
      I mean seriously folks, is it really too hard to ask for sharks with friggin' gigavolt-multimegampere proton beams strapped to their forehead?

    • Re: (Score:3, Funny)

      by CarpetShark ( 865376 )

      I mean, it has a frickin' gigavolt-multimegampere proton beam

      My car has multiple photon beams, powered by an engine generating up to 100000 volts many thousands of times per second. It's not as impressive as it sounds, though --- my torch has a photon beam too.

      • Re: (Score:3, Informative)

        by x2A ( 858210 )

        Protons and photons are different tho. I doubt your torch has a proton beam.

  • Great idea but pie in the sky... (Score:5, Interesting)

    by Cheerio Boy ( 82178 ) * on Sunday February 01, 2009 @11:53AM (#26684565) Homepage Journal
    I'm all for ideas like this but we won't be building things like this until we, as a planet, have a permanent manufacturing presence in space.

    Moon colony, orbiting L5 colony, whatever it is it must be permanent and able to manufacture using locally sourced materials because building something like this from within the gravity well doesn't make economic sense.

    • Re:Great idea but pie in the sky... (Score:5, Funny)

      by xch13fx ( 1463819 ) on Sunday February 01, 2009 @12:54PM (#26685029)
      If anyone needs a colonist I was recently laid off. I can weld and swim well.(You swim to move in zero g right?).

    • Re: (Score:3, Insightful)

      by TubeSteak ( 669689 )

      Moon colony, orbiting L5 colony, whatever it is it must be permanent and able to manufacture using locally sourced materials because building something like this from within the gravity well doesn't make economic sense.

      Under what set of conditions does it make any sense to launch a manufacturing plant into space, then send up raw materials? I assume that's what you mean by "locally sourced" because there isn't any 'local' material at the L5 point.

      How would that ever be cheaper than launching pre-built sections and assembling them in orbit?

      • Re:Great idea but pie in the sky... (Score:5, Insightful)

        by Cheerio Boy ( 82178 ) * on Sunday February 01, 2009 @01:13PM (#26685179) Homepage Journal

        Moon colony, orbiting L5 colony, whatever it is it must be permanent and able to manufacture using locally sourced materials because building something like this from within the gravity well doesn't make economic sense.

        Under what set of conditions does it make any sense to launch a manufacturing plant into space, then send up raw materials? I assume that's what you mean by "locally sourced" because there isn't any 'local' material at the L5 point.

        How would that ever be cheaper than launching pre-built sections and assembling them in orbit?

        No what I meant by locally sourced materials was either moon mined materials or asteroid mined materials. Probably the latter as I believe things like iron are a little weak [neiu.edu] on the moon.

        There's no way shipping ANYTHING up from the gravity well would allow us to build a ship of this nature within any reasonable time frame with the exception of using absolutely huge space elevators.

        • There's no way shipping ANYTHING up from the gravity well would allow us to build a ship of this nature within any reasonable time frame with the exception of using absolutely huge space elevators.

          *THE* gravity well?

          The moon has one too. Asteroids have a different but similar problem in being so far away and having such different orbital mechanics.

          What exactly are you proposing?

          • Re:Great idea but pie in the sky... (Score:5, Interesting)

            by Cheerio Boy ( 82178 ) * on Sunday February 01, 2009 @02:04PM (#26685601) Homepage Journal

            There's no way shipping ANYTHING up from the gravity well would allow us to build a ship of this nature within any reasonable time frame with the exception of using absolutely huge space elevators.

            *THE* gravity well?

            The moon has one too. Asteroids have a different but similar problem in being so far away and having such different orbital mechanics.

            What exactly are you proposing?

            For practical engineering purposes the gravity well of the moon is weak enough to not be a problem for the transportation of materials off it's surface.

            Asteroids do have gravity obviously but almost nothing due to their size. Thus materials transported from them are again easy to move into open space.

            What I'm proposing is this:

            1) Establish a colony on the moon or at L5.

            2) Use moon materials to build the manufacturing framework.

            3) Construct mining ships for asteroid field work.

            4) Mine asteroids and use the materials to construct the large-scale interplanetary transport.

            Now while this is a workable plan it is _also_ pie-in-the-sky as we can't even get our collective butts to agree on how to get a primary established off planet.

            • For practical engineering purposes the gravity well of the moon is weak enough to not be a problem for the transportation of materials off it's surface.

              You mean, it's less than earth and that makes it less of a problem, but it's still a gravity well, and your wishing it away won't make it so.

              Asteroids do have gravity obviously but almost nothing due to their size.

              I asked about asteroids having different orbits and being a long ways away. It's not just the orbital planes being different, but there are speed differences.

              A lot of energy to expend in both places.

              • You've got me on both points.

                But neither problem is insurmountable as an engineering challenge.

                My point is that either one would have to happen to create a practical material source in space _before_ a serious interplanetary ship would be feasible.
                • Come on guys, you can figure this out. It isn't rocket scien...never mind.

              • The delta v between your typical Amor class earth crossing asteroid and the Earth-Moon system is on the order of a few meters per second. In other words if you could stand on it and chuck a rock, you could hit the Earth.

                Existing propulsion technology could easily move one of these rocks around. It would be expensive and take time, but it could probably be done without requiring the invention of any fundamentally new technology.

                A 100 meter diameter rock like Apophis would mass on the order of a gigaton or so

              • Re: (Score:2)

                by HiThere ( 15173 )

                You use catapults! From the moon, the catapults lift the materials into high lunar orbit. From the asteroids, the catapults act as a rocket.

                Actually, while the "Mass driver" would work, I think that a rocket would be better. Most asteroids have a lot of methane or other low vaporizing material on them (or in them). Use that with a solar mirror to heat them into a rocket exhaust. Or possibly convert them into fuel for an ion rocket. It'd be slow, but fast compared to something that only ran for a shot

            • Re: (Score:2, Funny)

              by wasmoke ( 1055116 )
              You forgot one: 5) PROFIT!
          • The moon has a number of advantages for launching raw materials into its local space. The lack of an atmosphere is the major one. You can use even a very weak mass driver to shunt something into a path high enough for a low lunar orbit at which point you could use any slow but efficient electric thrusters of your choice. It helps a lot to save on fuel if you can make a larger gun to fire stuff higher of course, if you can get resources into something approximating a stable orbit with only a tiny thrust of i

    • Your inability to comprehense the feasibility of this design does not make it "pie in the sky".

      My whole life, I ran into people claiming that this and that is so far away and today still impossible, because they did not remotely know what was already done and possible.

      Project Orion (same thing, but with fission bombs only) was already completely possible in the 60s!. Fusion bombs have since been perfected. They are not much harder anyway. So this is no far thought. It's the logical next step. At least if we

      • Your inability to comprehense the feasibility of this design does not make it "pie in the sky".

        I comprehend the idea just fine. But looking at our track record of growth I maintain that we won't get to this project without a close permanent manufacturing facility in space or space elevators.

        My whole life, I ran into people claiming that this and that is so far away and today still impossible, because they did not remotely know what was already done and possible.

        Project Orion (same thing, but with fission bombs only) was already completely possible in the 60s!. Fusion bombs have since been perfected. They are not much harder anyway. So this is no far thought. It's the logical next step. At least if we want to see interstellar travel in our lifetime.

        And there's nothing in the world that I would like to see more.

        I too would love to see that in my lifetime but hoping and wishing won't build a starship and nobody I know of is going to commute both themselves and materials from the surface of the earth to high orbit or open space to construct a ship of this nature for the 5 - 10 years minimum it would take our slow asses to

  • My memories of Edward Teller (Score:5, Interesting)

    by MarkWatson ( 189759 ) on Sunday February 01, 2009 @11:56AM (#26684589) Homepage

    Edward Teller hired my Dad into the Physics department at UC Berkeley and I remember him as a gentleman - he was occasionally at our house. Once my parents had a costume party and Teller was provided with a bird costume - he did not want to wear the mask so he had these big white wings on. The SF Chronicle columnist Herb Caen ran a story the next day saying that Teller was dressed as the angel of peace. Until Teller died a few years ago, my Dad would occasionally travel to Berkeley to visit with him.

    • Re: (Score:2)

      by stox ( 131684 )

      Edward was a remarkable man. Fortunately, not too long before his death, he published his memoirs, which give great insight into his thoughts and outlooks. He was far from perfect, but no real man is.

    • Re:My memories of Edward Teller (Score:4, Informative)

      by Vellmont ( 569020 ) on Sunday February 01, 2009 @01:40PM (#26685363) Homepage


      The SF Chronicle columnist Herb Caen ran a story the next day saying that Teller was dressed as the angel of peace.

      An interesting story about a man who was awarded the first Ig-nobel prize for peace: [improbable.com]

      for his lifelong efforts to change the meaning of peace as we know it.

  • Then a miracle occurs... (Score:3, Informative)

    by Monsieur Canard ( 766354 ) on Sunday February 01, 2009 @11:56AM (#26684595)

    One of my grad school profs worked on a project like this. The concept involved a ship farting (for lack of a more appropriate term) out a series of small fusion bombs. When they went off the heat would cause the shielding at the rear of the ship to sublimate, and this ablation process would drive the ship. As I recall there were only two teensy problems with this: 1) even with the best shielding material available today, the intense heat from the detonation would still cause the maximum heat in the shield to occur at a depth greater than the surface (i.e. the shield would come off in great blobs instead of the slow steady ablation required for thrust) and 2) the amount of anti-matter required for the devices was only about a million times the total amount ever produced on Earth.

    But apart from that it worked like a champ.

    • A great way to make contact with aliens . . . (Score:4, Funny)

      by PolygamousRanchKid ( 1290638 ) on Sunday February 01, 2009 @12:12PM (#26684677)

      . . . speeding through their neighborhood whilst "farting out a series of small fusion bombs."

      They will come looking for us.

      "Hey, Earthling, is this your flatulent spacecraft that fouled our air? We'd just like to return it to you, by chucking it at one of your major cities."

    • What does anti-matter have to do with it?

      • Good question. Almost as good as what was a guy that sits on a space propulsion committee doing teaching Gaussian quadrature to a bunch of slacker engineers?

        I may have combined a couple of his papers on that one, I'll have to look when I get home. It may have been one using fusion and one using anti-matter. I loved hearing his stories about some of the papers he had to review as part of the committee, some were downright interesting, but most seemed to involve some sort of device that pissed-off the 2nd law

      • Re: (Score:2)

        by khallow ( 566160 )
        Antimatter can help kick off the fusion reaction.

  • We don't need more speed (Score:3, Insightful)

    by Anonymous Coward on Sunday February 01, 2009 @12:20PM (#26684751)

    All the interesting places are either within reach now or too far to go there at ANY speed. What we really need is to find a way to autonomously survive in space for a long time.

  • If it's good enough for the geometers [wikipedia.org], it's good enough for me.

  • That should have read... (Score:5, Insightful)

    by gyrogeerloose ( 849181 ) on Sunday February 01, 2009 @12:27PM (#26684819) Journal

    ... Edward Teller, the self-described father of the hydrogen bomb.

    Other people who worked on the project tend to disagree with that title.

    • I does not matter (Score:2, Interesting)

      by Gabest ( 852807 )
      Because they are all dead or going to be soon.

    • I'd characterize Teller's role in the H-bomb as similar to Oppenheimer's role for the A-bomb. As Oppenheimer is routinely called the "father" of the A-bomb, it seems reasonable to use the same language. Obviously, both projects were the result of a substantial number of people working a lot of hours.

    • Re: (Score:2)

      by Scaba ( 183684 )

      My mother had the same problem whenever my father would describe himself as such. How could he be the father when she worked on the project, too?

  • Kinda optimistic (Score:3, Informative)

    by Ancient_Hacker ( 751168 ) on Sunday February 01, 2009 @12:42PM (#26684945)

    Hmmm, if we can't build lasers and power supplies like that on Earth, even given tens of years and billions of $, how soon will these be doable in outer space, with 100% reliability.

    The old project Orion looked into atomic kabang propulsion. There were a few major showstoppers-- two dud impulses in a row and the pusher plate goes flying off into space. No way on Earth to test it. Which is kinda important for a device that has to be 100% reliable with no misfires.

    Also the idea of discharging all those Joules in 10 nanoseconds is mighty ambitious-- just the inductance of the objects limits the rate of current rise to a whole lot more than that.

  • Where is the ZPM?

    • Actually in the Stargate universe currently (end of Season 5) the humans of Earth have multiple ZPMs. Spoilers ahead if you haven't seen the last episode of Season 5 yet.

      .

      .

      .

      Two were taken back to the Milky Way after the Replicators occupying Atlantis back in Season 3 were destroyed. One of those was put aboard the Odyssey to help give them a chance against the Ori. It's never again mentioned but it's likely still there. In addition I find it interesting that at the time of the last Atlantis episode the

  • Oh, but it gets better (Score:4, Insightful)

    by capn_nemo ( 667943 ) on Sunday February 01, 2009 @01:46PM (#26685429) Homepage

    If you read the proposal, you'll note that the proposed method of working in space seems to be that the rocket engine actually fires in two directions - first, it fires a very high energy plasma beam AT THE SPACESHIP, which, in the vacuum of space, turns the whole assembly into a Gigavolt capacitor. THEN the spaceship fires a GV proton beam back at the rocket. This proton beam then ignites a classic fission explosion (using Deuterium-Tritium), but "very small", and this DT explosion ignites a second, much more explosive Deuterium-only fusion explosion AWAY FROM THE SPACECRAFT. Repeat one million times per second, or as needed.

    What could possibly go wrong?

    If that's not exciting enough, the whole plasma/proton beam doesn't work on earth, so, hey, we use a disposable argon laser, which can generate a lot of power, but (sadly), is really inefficient. But wait, we can fix that! All you have to do is set off a small hexogene explosion around your rod of solid argon, and the laser will suddenly work at 80% efficiency. Oh, repeat that every microsecond or so.

    Honestly though, if you can get past the insane energies involved, he's come up with a rather brilliant way to use readily available fuel (Deuterium, as opposed to Deuterium Tritium, which is hard to come by), and using a whole chain of events, make the process really efficient (i.e. you need a lot less mass to make all this work). And, since your main burn is fusion (which consumes the fission by-products), not a lot of radiation to speak of (oh, well, there are some pesky neutrons, but who doesn't like neutrons?)

  • reach 12% of the speed of light on its way to Barnard's Star.

    That is fast, but since Barnard's Star is 6 light years away, assuming a constant acceleration and deceleration it would still take 100 years to arrive.

    • Re: (Score:3, Informative)

      by extrasolar ( 28341 )

      According to google, it will take 50 years [google.com] to get there, unless you're talking about a round trip. Personally, I'd just be happy with a space probe. The six years it would take to receive information from the post, and for it to receive commands, would be a pain in the ass though.

  • Amazing (Score:2, Offtopic)

    by Eravnrekaree ( 467752 )

    Building a starship is the least of our concerns. It baffles me that we are discussing building a fusion spaceship when it seems that very little is being done to get fusion working for making our energy here on earth. Our priorities are all mixed up. While we are spending billions on wars to give money to banks so they can use it to by their yachts, we desperately need to be spending that money on fusion and clean, environmentally friendly energy sources NOW. We cant afford to wait any more on this.

    It amaz

    • If fusion is feasible for a spaceship, why the hell are we not building fusion plants right now or at least spending billions on development of this.

      I think the short answer to that is that fusion power is probably not feasible for a spaceship. It's just easy for somebody to pretend it's feasible while they're writing a pie-in-the-sky paper about interstellar spaceships.

      If we can develop fusion, global warming is solved and we dont have to worry about it anymore. Then why are we not doing it. Why is it sometimes I get the feeling that while everyone moans about global warming, no one wants to take the initiative and actually fix the problem?

      I agree that switching all our energy production to fusion would help with pollution and CO2 production, but there's at least a few climate scientists that think that we've already dumped so much stuff into our atmosphere that we'll still have something to worry about even if CO2 produc

      • I do quite a bit. I ride the bus a lot, even though this is a great inconvenience. I would be happy to ride it if it were made convenient enough to do it. But the republican government here seems to like the idea of flooded coastal cities so they do not want to do anything to make public transit better. I use a clothesline (which is, astonishingly banned in places, which should be illegal!). I turn off lights. I dont run the AC unless its absolute unbearable without it. I recycle everything they will let me

        • Glad to hear it, even though it does make me a real asshole for putting you on the spot. :) If everybody making noise about global warming did that much, we'd probably be a lot better off.

    • If we can develop fusion, global warming is solved and we dont have to worry about it anymore. Then why are we not doing it

      We are doing it.

      Fusion in a "make H fuse into He" sense is fairly easy. Build a bomb, set it off, and presto - fusion.

      Fusion as in a "make atoms fuse in a controlled setting" is harder, but still done on a fairly regular basis.

      Fusion as in "create a fusion reaction that produces more energy that you spend creating the reaction" is fucking hard. Which is why we do #2 at all, and why you don't have unmetered power.

      (Oh, and if all you care about is global warming, nuclear fission's perfectly suitable. Hell,

  • Alpha Centauri A and B are more likely to harbor an earth like planet... not to mention are almost 2 LY closer.

    If you want some red dwarf action, swing by Proxima on the way.

  • He must be setting NASA up for an other "Mars Climate Orbiter" kind of disaster.

    Whatever may be the reason, on most of the paper, his calculations and figures are in the obsolete CGS system (Centimeter, Grams, Seconds). Forces are in dynes, pressures in g/cm^2, etc.

    And then you see later in the paper Amperes and Watts (which are SI units).

    CGS and SI (or MKS) don't mix.

  • Fusion is EASY/Maybe they should have built Orion (Score:3)

    by w0mprat ( 1317953 ) on Monday February 02, 2009 @02:34AM (#26691057)
    I wondered why many fusion drive proposals are the slightly absurd mini-bomb machine gun kind, then realised perhaps it is because the Orion program really was that awesome in a nuclear-steam punk fantasy kind of way. However ludicrous it is to detonate 1000 nuclear warheads sequentially to reach orbit, you had to admit it'd be super-cool. http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) [wikipedia.org] "This extreme design could be built with materials and techniques that could be obtained in 1958 or were anticipated to be available shortly after."

    Yet these equivalent fusion-based proposals seem to be only plausible with some assumptions of technological advancement, rather than with assumptions that people wouldn't mind the irreparable damage to the earths biosphere.

    I think the approach is all wrong by many proposals so far. Thing is, we can create and contain fusion right now, and you can do it your backyard (no kidding - see lower). I think a plausible fusion drive would be something like a Bussard electrostatic confinement based drive. Essentially you are accelerating ions to high enough velocity for fusion, but allowing some to escape by a neutral charged nozzle.

    We don't have fusion reactors right now that break even in any practical generative fashion, however that is absolutely not necessary. Give up the need to generate power from fusion, for example use an existing fission pile to power the thing, and you start to get results. The high-velocity fusion products become a nice boost to your specific impulse, along with your exhaust velocity much higher than any Ion or VASMIR thruster for any high-energy fuel leaking out the rear.

    Ditch the perfectionist science and apply practical engineering and tune the thing for efficiency. Go to the stars.

    Interestingly, electrostatic inertial confinement in a hard vacuum doesn't even need reactor walls .

    What makes this even more exciting is that hobbyists build electrostatic confinement devices, and even get fusion reactions. Oh, OpenSource too.

    http://www.fusor.net/ [fusor.net]

    http://en.wikipedia.org/wiki/Inertial_electrostatic_confinement [wikipedia.org]

    Now figure out how to make a drive out of a Fusor, strap some solar cells on it, and convince a private space launch company to put in orbit.

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