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Science Technology

New Lab Consolidates Propulsion Research Areas 47

Posted by timothy from the until-there's-dilithium-crystals dept.
zoid.com writes: "Nuclear-fusion drives, anti-matter protons and solar sails? NASA's Marshall Space Flight Center broke ground on a new administration and lab building for the Propulsion Research Center today. This lab will will be used to develop new propulsion concepts and techniques for the future of space exploration."
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New Lab Consolidates Propulsion Research Areas More

New Lab Consolidates Propulsion Research Areas

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  • Rep. Cramer compares the old lab to an old car garage, with concrete floors and tin roofs. Hopefully a more appropriate working environment will be more conducive to thought and research. It would be great if they actually managed to design a functional anti-matter thurster.
    • It would be great if they actually managed to design a functional anti-matter thurster.

      There are two designs already that I know of that would certainly work. The problem is that antimatter is a bugger to produce (well, antiprotons, at least).
      • There are two designs already that I know of that would certainly work. The problem is that antimatter is a bugger to produce (well, antiprotons, at least).

        That would be why I specified a functional thruster. The anti-matter generator would most likely need to be part of the unit. I doubt that generating it earth-side and carrying large quantities would be that good of an idea, but an onboard generator pumping out a small but constant stream would be ideal.

        • That would be why I specified a functional thruster. The anti-matter generator would most likely need to be part of the unit. I doubt that generating it earth-side and carrying large quantities would be that good of an idea, but an onboard generator pumping out a small but constant stream would be ideal.

          The problem with this is that you'd be better off just using whatever power source you'd be generating the antimatter with. Even with perfect efficiency, you won't get out any more power than you put in (antimatter generators use energy-to-matter conversion to make the antimatter).

          The only known ways of producing antimatter are about a million-to-one inefficient. You're definitely generating it on the ground, where you have as much power as you need.
  • Fusion reactors and anti-matter drives sound cool, but do the math ... assuming these drives can propel a craft at one-tenth the speed of light, which is a speed of approximately 66.9 Million Miles Per Hour, it would still take 30 years to reach the nearest star.

    • Only 30 years, thats almost nothing honestly. Lets say we send a probe to go there and back. In just 33 (assuming 3 years for the signal to get back) years we'd have major knowlege of another solar system. We sent our probes to pluto 30 years ago, why would we do any different today.

    • Fortunately, we don't *need* star trek. (Score:4, Interesting)

      by Christopher Thomas ( 11717 ) on Monday July 08, 2002 @08:15PM (#3846051)
      Fusion reactors and anti-matter drives sound cool, but do the math ... assuming these drives can propel a craft at one-tenth the speed of light, which is a speed of approximately 66.9 Million Miles Per Hour, it would still take 30 years to reach the nearest star.

      Even if we don't reach the nearest star (and 10 percent of C is very optimistic for any drive built in the near future), we'd be able to reach anywhere in the solar system with much, much better transit times and fuel to mass ratios than we currently can. This is what we'd need to do widespread exploration/colonization.

      Assuming we _can_ get to 10% C, it would _definitely_ be worth it to send probes to nearby systems. We know we can build craft that last that long, and it's very unlikely we'd find a better drive in only 30 years.

      In short, advanced drives would still be very, very useful.
    • Fusion reactors and anti-matter drives sound cool, but do the math ...

      It is true that they would probably take 30 years to reach the nearest star, but this is only an issue if you are talking manned missions. If you are sending a probe then this is less of an issue, since there is no life support to take worry about and the ground crew would be there to monitor anything ineteresting that the probe might sense.

      The other thing that you need to take into account is that we didn't go from the stone wheel to the jet-engine in one leap. We had to go through a number of technological steps and also change our perceptions a number of times. It is the same with space travel, we can't even hope to build an FTL vehicle ( if it is possible ), until we have gone through another few technological steps and changing our perceptions of things a few more times.

      "Start with one step and keep on walking." or "You need to learn to walk before you run." - either way the two philosphies can be used to describe technological progress.
  • It's what you do with it.

    What's the point of messing about with antimatter right now? The amount of antimatter that has ever been made is smaller than a pinhead. The use of this for a propulsion system- that dog does not fly.

    I mean, cmon; NASA is an aging, flabby, inept (X33), and misguided, accident prone (Challenger) and not well managed (ISS) organization.

    Costs in most other parts of the world are far lower, and this is not simply because their engineers are cheaper; there has been studies on that. The ISS is predominately of Russian build and launch, and again Russia managed it for a tiny fraction of what it would have cost NASA.

    America deserves far better for their money. Space is important, NASA achieves little with their huge budget.

    True private launch infrastructure is the way to go; how a left wing organisation like NASA has survived this long in a country like America is completely beyond me.

    • What's the point of messing about with antimatter right now? The amount of antimatter that has ever been made is smaller than a pinhead.

      But wouldn't it be nice to be able to *use* antimatter in a propulsion system when/if we ever _do_ figure out how to build it in quantity, instead twiddling our thumbs and spending more decades figuring out how to build the drives?

      Better yet, if a practical antimatter drive scheme is found, it would suddenly become worth producing more antimatter. The reason so little has been produced is that current applications (physics research) don't need much.

      Re. quantity, the most feasible drive plans I've seen call for small quantities of antimatter to be used to induce fusion in deuterium pellets. You wouldn't need tonnes of the stuff.
      • From what I've seen the hard bit by far is getting into space at all. Once you're there, conventional fission can get us about the solar system plenty fast enough. The main limitation isn't energy- it's materials. We really need a cheap launch system!

        Deuterium fusion? Don't make me laugh. Containment is a total nightmare. It's been 50 years away for 50 years; except now it's only 30 years away; maybe, or maybe they're just being more optimistic because someone was going to cut their funding. And that's just getting it to fuse and stay contained; getting electricity from it- that's almost equally as hard.

        I went to a talk on positron manufacture and its possible use on an unmanned air vehicle. It turns out that the entire output of the world so far and probably the next 20 years wasn't enough to make a single unmanned vehicle work for 1 minute. Production rates were more than 1000x lower than necessary for even that. And even if they could- storage of large quantities is currently well beyond the state of the art.

        Large quantities of antimatter is practically the definition of 'unobtainium' right now.

        • From what I've seen the hard bit by far is getting into space at all. Once you're there, conventional fission can get us about the solar system plenty fast enough. The main limitation isn't energy- it's materials. We really need a cheap launch system!

          Actually, unless you're talking about a nuclear-electric ion drive, fission drives are pretty lousy. The reason is that in a direct contact style drive like NERVA your core temperature has to be low enough not to melt your materials or let your exhaust gas etch the walls. This limits your exhaust temperature to the range that you'd get with chemical rockets. This means that your Isp isn't going to be much better than chemical rockets.

          For anything inside the asteroid belt, solar power is probably better than nuclear, as it weighs less per unit power generation.

          Deuterium fusion? Don't make me laugh. Containment is a total nightmare. It's been 50 years away for 50 years; except now it's only 30 years away; maybe, or maybe they're just being more optimistic because someone was going to cut their funding. And that's just getting it to fuse and stay contained; getting electricity from it- that's almost equally as hard.

          Read about fusion drives before criticizing them. You don't generate electricity from them or run them steady-state. You perform inertial confinement fusion on micropellets, one pellet at a time, in a magnetic field so that your exhaust goes mostly in one direction. This is much, much easier than trying to extract power from the fusion reaction at reasonable efficiency.

          Antimatter works wonderfully as a trigger because it doesn't suffer from laser-ignition's problem of reflecting off of the pellets once they become plasma.

          I went to a talk on positron manufacture and its possible use on an unmanned air vehicle.

          Positrons can be manufactured in your basement. But they're useless for space travel or any other propulsion because they're far too light (you can't store enough mass to do anything useful). Antiprotons are the fuel of choice, as they have a charge to mass ratio 2000 times greater. Depending on the storage scheme, you may also choose to let them bind to positrons to form antihydrogen and store that (you can suspend it at extremely low temperatures at far higher densities than you could store antiprotons in an ion trap).

          Antiprotons, however, can only be made at million-to-one inefficiencies using a 10+ GeV accelerator. Doing this in space would be even more of a pain in the neck than on Earth, partly because you need a bigarsed device and partly because you need a bigger-arsed power plant (though you do get hard vacuum for free, which is a bonus).

          Large quantities of antimatter is practically the definition of 'unobtainium' right now.

          This is why the antimatter-triggered fusion rocket is the most promising design for an interstellar craft. It needed a few hundred micrograms, which is within our capacity to produce.
          • This is why the antimatter-triggered fusion rocket is the most promising design for an interstellar craft. It needed a few hundred micrograms, which is within our capacity to produce.

            Look we haven't even worked out how to get off the planet cheaply- and interplanetary hasn't been done yet, and you're worried about interstellar?

            • This is why the antimatter-triggered fusion rocket is the most promising design for an interstellar craft. It needed a few hundred micrograms, which is within our capacity to produce.

              Look we haven't even worked out how to get off the planet cheaply- and interplanetary hasn't been done yet, and you're worried about interstellar?

              Yes.

              Largely because these are orthogonal problems. Ground to orbit needs a high-thrust drive, while in-space flight needs a high-Isp, low-thrust drive.

              If we _can_ build an interstellar probe, why shouldn't we? It would teach us far more about other star systems than we're likely to learn by any other means.
              • If we _can_ build an interstellar probe, why shouldn't we? It would teach us far more about other star systems than we're likely to learn by any other means.

                We haven't even investigated this one yet! The cost for launching rockets should be near to $100/kg. It's currently at $2600/kg. If it reaches $100/kg then pretty much anyone reasonably well off can get to go to space. No amount of antimatter rockets can do this. Building large equipment in space is actually easier than building it on the ground; and energy to make antimatter is easy to collect up there.

                It's just like Christopher Columbus just discovered America and you're planning to go to the moon! (Why not, the problems are orthogonal!)

                • We haven't even investigated this one yet! The cost for launching rockets should be near to $100/kg. It's currently at $2600/kg. If it reaches $100/kg then pretty much anyone reasonably well off can get to go to space. No amount of antimatter rockets can do this. Building large equipment in space is actually easier than building it on the ground; and energy to make antimatter is easy to collect up there.

                  We've already gone over this.

                  Launch cost for the ship itself at *current* prices is cheap compared to the cost of the antimatter, so launch cost for the ship is irrlelevant.

                  For the antimatter generation - which is cheaper? Carrying a billion tonnes of power plant and particle accelerator into space, or leaving it on the ground and carrying a hundred micrograms of antimatter into space?

                  There is no reason to generate the antimatter in space. We don't have a shortage of power on the ground, and we have power plant and accelerator designs that have already been field-tested on Earth.

                  Ground-to-orbit cost for building the probe is a non-issue. The only relevant issue is whether we think the research benefit from visiting a nearby star system is worth the cost of the antimatter and ship design engineering. So far, other projects have a better research benefit:cost ratio.
                  • For the antimatter generation - which is cheaper? Carrying a billion tonnes of power plant and particle accelerator into space, or leaving it on the ground and carrying a hundred micrograms of antimatter into space?

                    Of the two I'd say building the billion tonnes of power plant (they get heavy these days these power plants!) in space, and building the rocket there too is cheaper.

  • Hmm.. Very Interesting (Score:2, Interesting)

    by tspears ( 569834 )

    I'm not so sure what I think about this. I'm all for increased spending in advanced propulsion research, but it should be done with caution.

    "Anti-matter is several years out," Rodgers said

    HAHA several YEARS out? yeah right! Currently, it would cost more than the GNP of the United States to merely light a 75 watt light bulb with current Antimatter Power Techniques. (This is what I have heard, maybe this is no longer true, but I don't think anti-matter production techniques have improved that much in the last six months since I heard this).I would say it's more than just a few years out.

    The work on anti-matter will be at the level of the atom, so there will be little safety threat in case of an accident, said Harry Gerrish, a chief research engineer at the lab.

    Although Anti-matter power techniques may not leave a risk of nuclear fallout which is a major concern with Nuclear Fission, it still involves harnessing a ridiculously large amount of energy. We should be more concerned about a technology like this falling into people with malicious intent in mind, or those who simply don't know what they are doing. I'm sure that once anti-matter technology progresses to a certain level, it will be possible to annihalate the planet with relative ease. Perhaps technologies like anti-matter should be developed only after our society becomes mature enough that it can use and harness technologies such as anti-matter without the risk of destroying itself in the process.

    The ultimate form of propulsion technology may not lie in making faster and better propulsion systems, such as antimatter, but the ability to control the mass and inertia of an object moving through space.A relativly new theory of inertia, in which the electromagnetic energy in the Zero-Point Field interacts with the electromagnetic and strong forces of atomswould provide a reason for inertia to happen. Until now we have known that inertia occurs, but beyond the fact that it is directly related with the mass of an object, scientists haven't been able to find the mechanism for it to occur. If these interactions could be controlled, those between the zero-point field and the electromagnetic bonds of atoms, an object's mass could be deminished to zero, and the object could travel at very close to the speed of light with almost no energy propeling it.

    See Inertia as a Zero-Point Lorenz Force by B. Haisch [calphysics.org]for further information.

    • I think your concern about anti-matter technology falling into the wrong hands is a little bit premature. Let's not forget that propulsion difficulties really originate from the fact that the energy densities of any fuel are so low that to generate enough energy for significant propulsion you have to have so much fuel that the fuels own mass becomes a problem. The more energy you need the more massive the craft has to be to contain the fuel. If a craft didn't have the mass of the fuel/propulsion system it wouldn't need anywhere neer the amount of energy produced by today's launch vehicles/space craft to satisfy their thrust needs.

      What all this means is that the amount of anti-matter fuel needed to propel a craft would be very small and would in fact need to produce less energy than todays rockets do. It wouldn't have to lift as much (no real mass contribution from the propulsion system). Basicly this means that the amount of anti-matter needed to be usefull wouldn't have as much punch as the booster rockets on the space shuttle, so it certainly wouldn't be capable of destroying the planet. I know this was a little bit rambling, but I hope you get my point. The Zero-Point stuff is also very interesting. It get's to the main crux of the problem of lowering the mass of the craft. And that's really what an anti-matter propulsion system does. It doesn't give the craft more punch (it actually lowers it), it simply lowers the mass of the craft more than it lowers the punch of the propulsion system.
      • Yeah you make a really good point-- that propellant accounts for most of the mass of a spacecraft. If you need to send a spacecraft a given distance with X amount of propellant, you will need X^2 propellant to be able to slow the space craft. But even if you eliminate the propellant all together, the payload still has mass. I think it's fair to say that at least lightspeed is pretty much needed for any serious space exploration outside our closest neighboring stars. According to General Relativity an infinite amount of energy is required to propel any object with mass faster than light. This has been proven in particle accelertators. Particle Physicists can make an electron go 95% speed of light pretty easily. But 99% requires more energy, even more for 99.9%, even more for 99.99, etc, etc onto an infinite number of decimal places, and thus an infinite amount of energy. This is why it is impossible to make anything go faster than light. For this reason, IMO, The ability to alter the ZPF to reduce the mass of a moving object to zero is pretty much needed if we ever want to do any serious space exploration. But anti-matter is certainly a start, but I don't think its the ultimate solution.
        • Mass is certainly the issue. I think anti-matter will find applications in exploration of the solar system including far flung regions like the oort cloud; however I agree with you that on its own it can't solve the intersteller dilemma.
      • Have there been any successful reproductions of a zero-point experiment?

        I'm not trying to come down on someone like 'the establishment' and laugh at that-which-is-different.

        Any experimental data to back up this theory, or is it all just a paper on a web site?
    • HAHA several YEARS out? yeah right! Currently, it would cost more than the GNP of the United States to merely light a 75 watt light bulb with current Antimatter Power Techniques. (This is what I have heard, maybe this is no longer true, but I don't think anti-matter production techniques have improved that much in the last six months since I heard this).I would say it's more than just a few years out.

      Doublecheck your source.

      Antiprotons (the type of antimatter we care about for fuel) are produced at about 1e6:1 inefficiency in current accelerators. Assume a system-wide inefficiency of 100:1 on top of this for good measure. That gives you 1e8 watts of power for every watt that goes into your hypothetical light bulb.

      That's 7.5e9 watts for your light bulb. At 5 cents per kilowatt-hour (3.6 MJ), that's about $100 per second (for 2.1e3 kW/h).

      Substantially less than the GNP.

      Hybrid antimatter/fusion craft (that use antimatter to trigger inertial confinement fusion) require on the order of one microgram of antimatter (actually a few hundred nanograms, but let's be lavish). At the efficiencies and costs listed above, it would cost $125 billion to produce the required amount of antimatter.

      The US's GNP, by comparison, is about $6.7 trillion.

      You'd still have to pay for the production facilities if you wanted to produce the antimatter quickly (it would take a century with our existing accelerators), but this would be at worst a comparable cost to the power used (the SSC was estimated at $20 billion, and it was a thousand times more powerful than needed).

      In short, antimatter production for spacecraft is feasible (maybe even better than I've painted, as production rigs built specifically to produce antimatter are more efficient than standard accelerators).
      • my bad, i remember hearing the GNP figure on some tv show. I did some research and now I know that it requires 2000 times as much energy to produce anti-matter than the energy you will obtain from it. However, isn't the issue storing the anti-protons for a long period of time, not so much producing them? If my memory is correct, current technology allows us to store 10^8 antiprotons for about a few days or so. Assuming we could reach 10%C we would have to be able to store anti-protons for about 40 years to reach the nearest star.
        • However, isn't the issue storing the anti-protons for a long period of time, not so much producing them? If my memory is correct, current technology allows us to store 10^8 antiprotons for about a few days or so. Assuming we could reach 10%C we would have to be able to store anti-protons for about 40 years to reach the nearest star.

          Penning traps and Paul traps should both be capable of storing antimatter for years, albeit at extremely low density (I think they did store a handful of antiprotons for a year to demonstrate this, but I don't have a citation offhand).

          If you have a very large trap, this might be enough to let you store a microgram of antimatter.

          An alternative would be to bind antiprotons and positrons as antihydrogen, freeze it, give the resulting pellet an electric charge, and then store that with electrostatic confinement. I *think* a scheme along these lines was proposed once, but I could very easily be wrong (heard about it many years ago). This would allow you to store as much antimatter as you could ever possibly produce.
  • That way we can brew a *really* hot cup of tea, not limited by any puny 100C boiling problems. Good superhot tea should yield a drive that would leave the Heart of Gold in the dust, and maybe even pass the Bistromath.
  • Just curious... don't we already have a national propulsion lab in JPL? I'm just going by the name as I don't know too much about it... ?

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