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Space Transportation

Fusion Rocket Could Take Us To Mars 171

New submitter imikem writes "University of Washington researchers and scientists at a Redmond-based space-propulsion company are building components of a fusion-powered rocket aimed to clear many of the hurdles that block deep space travel, including long times in transit, exorbitant costs and health risks. 'Using existing rocket fuels, it's nearly impossible for humans to explore much beyond Earth,' said lead researcher John Slough, a UW research associate professor of aeronautics and astronautics. 'We are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace.' 'The research team has developed a type of plasma that is encased in its own magnetic field. Nuclear fusion occurs when this plasma is compressed to high pressure with a magnetic field. The team has successfully tested this technique in the lab. Only a small amount of fusion is needed to power a rocket – a small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.'"
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Fusion Rocket Could Take Us To Mars

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  • by schneidafunk (795759) on Friday April 05, 2013 @10:47AM (#43368911)
    How is the electricity produced in the space ship for the nuclear fusion, would it also be nuclear? "The capacitors are hooked up to a giant magnet that houses the chamber where the fusion reaction will take place. With the flip of a switch, the capacitors are simultaneously triggered to deliver 1 million amps of electricity for a fraction of a second to the magnet, which quickly compresses the metal ring."
    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Their stated cycle time is 1 minute. Article says they fire for a "fraction of a second" to compress the metal rings, so the peak power generation needed would be 2-3 orders of magnitude lower than the instantaenous power usage. Small scale fission reactor like the sort on a nuclear submarine would do the trick. Or a radioisotope thermal generator:

      • You plan to send a submarine to Mars?

        • by Lithdren (605362)

          Why not? They're not that different from space ships in many ways.

          Both must keep high pressure and low pressure areas seperate and protected from one another. Both must supply the crew with life support functions and the ability to communicate. Sure keeping the ocean out vs keeping the atmosphere in is different, but thats a structual question, functionally it's pretty similar.

          By far the largest difference is a sub doesn't have a weight limit anywhere near as strict as a space ship, but that's more of a t

        • by cusco (717999)
          Just its power plant. They're extremely well-designed and quite safe.
        • by Shotgun (30919)

          It worked for the Yamamoto!

          ON STAR...BLAZERS

    • by MightyYar (622222)

      You put a big paddle wheel off the back and run generators with it.

    • You could probably run it off solar power, but I believe NASA has been looking to get approval to launch nuclear reactors into space again. NERVA-type engines still have inferior Isp compared to most of the fusion concepts out there - and whatever else it may be, using a fusion-based combustion chamber is going to be easier to make safe then a nuclear lightbulb type design. No need to shotgun blast a bunch of uranium into space/orbit/the atmosphere.

      • by Hentes (2461350)

        You could run it off anything if you limit the reaction rate accordingly. The problem is that the generated energy has to be stored in a roomful of capacitors, which won't fit on a rocket.

        • Depends how heavy that room is. And I suppose, how heavy the fuel is - you could justify launching a large, one-off ship that you then only have to send up fuel for. A 90 or 30 day trip to Mars would mean you'd be able to run regular missions shuttling between the two.

          • by Anonymous Coward

            Bingo. For a space mission they would optimize on capacitor energy density. For lab work they would use the cheapest capacitor available that does the job without regard to space/weight considerations.

            They article specifies a million Amps for a short duration (but fails to specify the duration or voltage needed). Here's a 2000A, 5 KG ultracapacitor. 1 million amps at 16V is achieveable in 2500 KG with a 1 second long burst.

    • They have a infographics [] that gives a lot of nice details.

      Mars Mission
      Power Source: 180 kW solar array
      Spacecraft Mass: 16 MT
      Payload Mass: 61 MT
      Propellent Mass: 57 MT

  • I don't see how putting five blades on the front and one more blade at the back and slightly above is going to improve things much. Going from two blades to five, increases the efficiency, I can see. Each stroke is like five strokes using a straight-edge. But at this point we are beyond the optimum in the law of marginal returns.

    Wait, you are talking about Gillett, aren't you?

  • But apparently there can be good things from Redmond, like nuclear fusion-powered spaceships :-).

  • As Silicon Dioxide (silica, a component of sand) is not noted for its fusing properties, I was guessing that the fusion would be from more typical materials: hydrogen, or perhaps helium.

    And while liquid hydrogen technology is well developed, liquid helium is a bit more difficult, and metallic hydrogen even more so. A "grain" of (metallic) hydrogen seems a bit beyond expectation. A grain-sized amount of hydrogen, I'd believe. But a tank of granulated metallic hydrogen?

    • by dAzED1 (33635)
      Is English not your first language? (honest question, sometimes nuances can be lost) "As small as a grain of sand" is just a phrase, used to denote something tiny. Sounds like a word or such just got left out of the phrase - I can assure you they're not trying to use actual sand for fusion. Redmond may have nutjobs living there, but doing that would be beyond even them.
      • Lithium deuteride ( [] ) can look like a grain of salt literally - it is just not as clear as NaCl.
        • by Lithdren (605362)

          "Honey can you pass the Lithium deuteride?"

          "You know you shouldn't eat that stuff so much hon, it's bad for your heart. Remember what the doctor said..."

          "Yeah yeah, I know it gives me bad hydrogen gas, but it tastes so good!"

      • I was, rather, pointing out that "small as a grain of sand" has little meaning when referring to gasses, where the amount of material depends on the pressure involved; it has rather more meaning when describing liquids and solids, which are much less compressable.

  • The Trisops [] machine at the University of Miami.

    Trisops was an experimental machine for the study of magnetic confinement of plasmas with the ultimate goal of producing fusion power. The configuration was a variation of a compact toroid, a toroidal (doughnut-shaped) structure of plasma and magnetic fields with no coils penetrating the center. It lost funding in its original form in 1978.
    The configuration was produced by combining two individual toroids produced by two conical pinch guns, located at either end of a length of Pyrex pipe with a constant magnetic guide field. The toroidal currents in the toroids were in opposite directions, so that they repelled each other. After coming to an equilibrium, they were adiabatically compressed by increasing the external field.

    Disclosure: I am one of the authors of the cited paper in the article and the author of the above Wikipedia article

  • What's not clear in the article is how they plan to power the drive... I seriously doubt solar will be sufficient (mostly due to the low insolation at Mars), which means nuclear. Which means *heavy*.

    • The real question is could you do an Earth launch with this? Because the "heavy" equation changes a lot if we could actually use something like this to get into space in the first place.

    • by X0563511 (793323)

      OK, think about those ridiculously high watt lasers. Recall how those are pulsed?

      So is this, with a period of a minute or so. (large amount of energy in a tiny period of time, with a long 'idle' phase between). A traditional fission reactor or RTG could be used to charge the capacitor system for this, as well as the other ship systems.

  • by khallow (566160) on Friday April 05, 2013 @11:15AM (#43369173)
    From the article:

    âoeUsing existing rocket fuels, itâ(TM)s nearly impossible for humans to explore much beyond Earth,â said lead researcher John Slough, a UW research associate professor of aeronautics and astronautics. âoeWe are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace.â


    NASA estimates a round-trip human expedition to Mars would take more than four years using current technology. The sheer amount of chemical rocket fuel needed in space would be extremely expensive â" the launch costs alone would be more than $12 billion.

    That's not true at all. Chemical rockets work as well. And with the Falcon Heavy in the near future, there's no reason to pay $12 billion in launch costs for a Mars mission, even if you use chemical rockets.

    Note also the phrase "take more than four years". That makes it sound like it takes two years to come and go from Mars. It really only takes six months with chemical rockets (plus some time for attaining Mars orbit, there's probably not going to be a direct landing on Mars due to the high risks of aerocapture) The reason it would take that long is because humans would be staying on the surface of Mars for at least two years. I doubt even instantaneous travel would cut off more than a year and a half.

    The more reasonable 90 day passage to Mars would takes six months off the travel time plus reduce the time needed to get into Mars orbit. It would also enable trips at any time rather than just during the most optimal trajectories. This really is the key constraint of chemical rockets.

    At this point, it is worth noting that there are other viable near future propulsion technologies as well. A key one is electric propulsion which can be solar or nuclear powered. It has a good mass fraction and travel times. Solar sails could be used to ferry radiation-immune loads over very slowly.

    • It's all about how much mass you can move though. More mass means more people, resources, landers arriving at Mars per trip, or more fuel which you can then blow on shorter trip times.

      We obviously can technically do it - but being cost-efficient and speedy are not solved challenges.

  • "could" take us to Mars as well.

    Unfortunately, harnessing fart power has proven much more elusive than fusion power.

  • So, this thing will go WHUMP! once a minute? It will be the most annoying and uncomfortable journey ever and forget of sleeping.
    • by mill3d (1647417)
      Could having many smaller units fired at close intervals help with the neck-breaker problem..?
  • These guys are claiming to have controlled thermonuclear fusion above breakeven. That's huge. No one has ever done that. If it works, we have a new major power source. They write: "Now, the key will be combining each isolated test into a final experiment that produces fusion using this technology". That's a Nobel prize if they succeed.

    This is too important to let NASA fuck up.

    • by Andy Dodd (701)

      Actually, they're not. What they're creating is more akin to uncontrolled thermonuclear fusion.

      Pretty much mini-bombs without the fission primary. Still pretty much bombs though. Usable for a rocket, not usable for electrical generation.

      Also, even if it doesn't achieve breakeven, it may still be able to achieve very good Isp - e.g. lots of thrust per gram of propellant mass.

  • Seems like an appropriate name for a very fast nuclear powered vehicle where we don't have to worry about disposing of the exhaust left in its wake right?

  • Only a small amount of fusion is needed to power a rocket – a small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.

    Fusion is a process, not a material.

    • by invid (163714)
      And for you grammar nazis, I meant 'proper noun'.
    • by invid (163714)
      Alright, I've just been to Wikipedia and what I really meant was 'concrete noun.' I've really got to go there first before I post anything.
  • by SlippyToad (240532) on Friday April 05, 2013 @11:58AM (#43369659)

    It was the NERVA rocket. it wasn't fusion, but it was a nuclear-powered rocket, and it would have easily made Mars our bitch.

    It was canceled to, fucking get this, no seriously, wait for it. It was canceled TO SAVE THE BUDGET because the politicos at the time were afraid a successful Mars rocket would "drag" the US into this huge "space program" where we'd explore the solar system and stuff. And that would cost a lot of money.

    Instead, we killed the NERVA rocket and saved our budget for Vietnam, which was a roaring success that paid incredible dividends . . . . oh, fuck.

    Anyway, this is nice to hear, but I'm not going to hold my fucking breath. Our national priorities are far too ass-backwards for something forward-looking like a Mars mission. I suspect the first people to land on Mars will likely be an international team, and America will be riding along in the back begging for a look out the front window from time to time.

    • by T.E.D. (34228) on Friday April 05, 2013 @01:52PM (#43371191)

      I went online looking to debunk this, but frankly its essentially true.

      Some further sad facts: In all of history there have been 12 human beings to set foot on another planet []. The youngest of them is now 77. Most of them are still alive (probably thanks to the extreme physical fitness required of astronauts), but the day is not too far off when they start dying, and we will be left with no living people who have visited another planet. Most US citizens were not born yet when this was going on.

      Space exploration is not something we are actively doing, but part of our history, joining its place alongside the Civil War and Lewis and Clark as "things to bore kids with in US History". If we tried doing it again, we've lost so much capability that it would probably take longer to accomplish, and cost more. We might as well post the poem Ozymandias next to our old Apollo artifacts in the museums:

      I met a traveller from an antique land Who said: Two vast and trunkless legs of stone Stand in the desart. Near them, on the sand, Half sunk, a shattered visage lies, whose frown, And wrinkled lip, and sneer of cold command, Tell that its sculptor well those passions read Which yet survive, stamped on these lifeless things, The hand that mocked them and the heart that fed: And on the pedestal these words appear: "My name is Ozymandias, king of kings: Look on my works, ye Mighty, and despair!" Nothing beside remains. Round the decay Of that colossal wreck, boundless and bare The lone and level sands stretch far away

    • It was canceled to, fucking get this, no seriously, wait for it. It was canceled TO SAVE THE BUDGET

      It was cancelled because costs were spiraling, performance decreasing, and a practical engine getting further away every day.

      • by kermidge (2221646)

        Also, in part, due to the increasing resistance of the nukaler nutters who protested against just about anything having to do with nuke stuff. Except of course for X-ray machines when they needed them. It was around this time that "Nuclear Magnetic Resonance" was re-named "Magnetic Resonance Imaging" so that hospitals could continue to have a useful diagnostic apparatus, and there began sweeping cutbacks in commercial power nukes due to greatly-increased costs for environmental and safety studies, and fin

    • by caywen (942955)

      Plus, god forbid we leak radiation into space. Keep space black!!

  • We are talking about fusion here so of course it perpetually will be available in 20 years.

    • by Teresita (982888)
      We are talking about fusion here so of course it perpetually will be available in 20 years.

      It's a real toss-up which will come first:

      1. Fusion power
      2. Artificial intelligence
      3. The Year of the Linux Desktop.
      • by jafac (1449)

        you're not factoring-in relativity. Fusion will be available in 20 years, unless you approach the speed of light, using a fusion drive, in which case, time slows down, and fusion will be available at some point further in the future.

  • by davebooth (101350) on Friday April 05, 2013 @12:24PM (#43370023)
    So suppose this works as described and we have a functional method of initiating pulses of controlled fusion in a rocket engine that when vented out the nozzle produces usable thrust. Let's make that nozzle thinner and a bit more tubular than conical - a few hefty magnets around to to keep all that fusing stuff in a nice thin stream. While we're at it lets anchor the other end of the rocket to something HUGE that the thrust isn't going to have a prayer of shifting. Except here we call it recoil, because if you have made a fusion rocket you have also created the other staple of grand space opera... A plasma cannon :)
  • And how not to kill all involved? No mention of that in the article from my quick read.

  • "We can't solve problems by using the same kind of thinking we used when we created them." - A. Einstein

Pound for pound, the amoeba is the most vicious animal on earth.