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NASA Power Space Transportation Science Technology

Leaked NASA Paper Suggests The 'Impossible' EM Drive Really Does Work (sciencealert.com) 711

A source close to NASA Eagleworks has leaked the test results of the 'impossible' EM Drive. While it's important to note that the results that have been leaked haven't been published in an academic journal, they do suggest that the system works and is capable of generating force of 1.2 millinewtons per kilowatt in a vacuum. ScienceAlert reports: The paper concludes that, after error measurements have been accounted for, the EM Drive generates force of 1.2 millinewtons per kilowatt in a vacuum. That's not an insignificant amount -- to put it into perspective, the super-powerful Hall thruster generates force of 60 millinewtons per kilowatt, an order of magnitude more than the EM Drive. But the Hall thruster uses fuel and requires a spacecraft to carry heavy propellants, and that extra weight could offset the higher thrust, the NASA Eagleworks team conclude in the paper. Light sails on the other hand, which are currently the most popular form of zero-propellant propulsion, use beams of sunlight to propel them forward rather than fuel. And they only generate force up to 6.67 micronewtons per kilowatt - two orders of magnitude less than NASA's EM Drive, says the paper. The NASA Eagleworks team measured the EM Drive's force using a low thrust pendulum at the Johnson Space Centre, and the tests were performed at 40, 60, and 80 watts. They were looking for any sign that the thrust could be a result of another anomaly in the system, but for now, that doesn't appear to be the case. "The test campaign included a null thrust test effort to identify any mundane sources of impulsive thrust, however none were identified," the team, led by Harold White, concluded in the paper. "Thrust data from forward, reverse, and null suggests that the system is consistently performing with a thrust to power ratio of 1.2 +/- 0.1 millinewtons per kilowatt." But the team does acknowledge that more research is needed to eliminate the possibility that thermal expansion could be somehow skewing the results. They also make it clear that this testing wasn't designed to optimize the thrust of the EM Drive, but simply to test whether it worked, so further tweaking could make the propulsion system more efficient and powerful.
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Leaked NASA Paper Suggests The 'Impossible' EM Drive Really Does Work

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  • by 50000BTU_barbecue ( 588132 ) on Monday November 07, 2016 @11:33PM (#53234703) Journal

    Because if Trump wins, we need a way to leave this planet...

    • by rossdee ( 243626 )

      To use this drive, you have to have already left the planet (be in orbit)

      I think gravity (at the suface) is about 10 Newtons per Kg
      so you'd need 8.5 MW per Kg of spacecraft
      So 17 Gigawatts forsomething the size of a shuttle
      We'd need a fusion reactor to power it

      • by mcswell ( 1102107 ) on Tuesday November 08, 2016 @01:37AM (#53235105)

        I thought we invented a fusion reactor that would go on the back of your car? Back in 2015, or before.

      • by Frankzy ( 4211685 ) on Tuesday November 08, 2016 @01:43AM (#53235123)
        It'd make an excellent engine for anything that gets lifted into space and is supposed to stay there for a long time, such as satellites...
  • by pushing-robot ( 1037830 ) on Monday November 07, 2016 @11:34PM (#53234713)

    The physical laws went out the door months ago.

    • It's just a rounding error in the universe. Nothing to worry about.
  • I need to see more (Score:2, Insightful)

    by batray ( 257663 )

    I need to see more than this article to convince me this works.

    • by presidenteloco ( 659168 ) on Tuesday November 08, 2016 @02:21AM (#53235223)

      Here's a link to the NASA paper on the apparently successful test: https://drive.google.com/file/... [google.com]

      And here is a presentation by the technology's inventor, Roger Shawyer https://vimeo.com/channels/Emd... [vimeo.com]

      Warning: Shawyer may well be brilliant, but he is the Anti-Musk in terms of his presenting and motivational skills. This guy could seriously announce a working warp drive in a way that would make people walk out of the presentation half way through. If he has funding problems, he needs to get someone else to present his technology and business case for him.

      • by serviscope_minor ( 664417 ) on Tuesday November 08, 2016 @04:27AM (#53235437) Journal

        Warning: Shawyer may well be brilliant,

        Nope. He first "derived" it using relativity and then ran with the result. It was obvious to just about every physicist ever that the result MUST have been bogus because relativity probably conserves momentum. The thing is, that's a mathematical proof so it holds always, no matter how clever your shape, how many springs or magnets you have or how smart you seem to be.

        It is literally impossible to have a reactionless thruster while constrained by the bounds of relativity. This is well known and thoroughly proven and is basic undergrad level physics, yet was apparently unknown to Shawyer.

        Not only that, he wouldn't even accept the result (i.e. Noether's theorem) until someone found the actual error in his working. It wa eventually found.

        Not a great start for brilliance.

        • by jandersen ( 462034 ) on Tuesday November 08, 2016 @05:14AM (#53235573)

          Well, if the drive works, then either the symmetry underlying conservation of momentum isn't entriely true (it wouldn't be the first time we discovered a surprising lack of symmetry, you know), or the drive isn't entirely reactionless. I think it is important to always be willing to keep an open mind, when we don't know for certain; what you are saying is "No, impossible, so I am not even going to look". Personally, I think preservation of momentum is true; so in my view there must be an escape of momentum that we haven't figured - if this works. This doesn't strike me as unthinkable - after all, energy is put in, so it must go somewhere. We just need to find an explanation.

          • by serviscope_minor ( 664417 ) on Tuesday November 08, 2016 @05:28AM (#53235605) Journal

            Well, if the drive works, then either the symmetry underlying conservation of momentum isn't entriely true (it wouldn't be the first time we discovered a surprising lack of symmetry, you know), or the drive isn't entirely reactionless.

            Yes, and that would mean it's a perpetual motion machine too. This would be pretty much the largest result in physics ever. You can see why people, including myself reckon it's completely bogus.

            or the drive isn't entirely reactionless

            Then it has to be generating reaction momentum from something. The thrust is too high for that.

            I think it is important to always be willing to keep an open mind, when we don't know for certain; what you are saying is "No, impossible, so I am not even going to look".

            No. You need to be open minded, but not so open minded that your brain falls out. What makes *this* perpetual motion machine different enough from all the others that it's worth a look? People can come up with bogus ideas faster than you can find flaws in them if you're barred from using tests like "does it conserve energy and/or momentum".

            so in my view there must be an escape of momentum that we haven't figured

            But we already understand the mechanisms for such things. You can synthesize mass from energy and then accelerate it, or just generate photons (which have momentum) and dump them out the back. But we know what the theoretical maximum efficiency for those is too. And the thrust here is too high. And if the thrust is too high, then it's a perpetual motion machine.

            • by Rufty ( 37223 )

              What makes *this* perpetual motion machine different enough from all the others that it's worth a look?

              Well, the lack of someone trying to sell something while hiding how it works. That and there have been several independent groups that have already looked and haven't found something obviously wrong. So the chances of this being a real effect have gone from one in millions to one in hundreds. The smart money is still on "there's something that's been overlooked". (Faster than light neutrinos = dodgy cable???) But at least this is now interesting.

            • >What makes *this* perpetual motion machine different enough from all the others that it's worth a look?

              The fact that we've had endless tests all apparently showing it working ? Don't get me wrong, I'm sceptical myself - it's entirely possible this will prove to be a measurement error in some subtle area we've never known to look for one - but if that is, that in itself would lead to new discoveries.
              Figuring out WHY this appears to produce thrust is basically guaranteed to lead to an advancement of physi

        • A better and far more plausible explanation for what's happening is here. [blogspot.com]

          And this fellow doesn't just do some hand waving. He has a theory, it is coherent, it is testable and falsifiable, and it also explains the galaxy rotation problem and the flyby anomaly accurately. As well as the EmDrive.

          He's worth reading.

      • by tp1024 ( 2409684 ) on Tuesday November 08, 2016 @05:49AM (#53235645)

        The problem with the paper is twofold:

        1) After one year, it is still not published in a peer reviewed journal. This happens on occasion. However:
        2) The data is about as flakey as it gets. Eg. the forces measured for the 60W power level range from 40 micronewton to 120 micronewton. This goes completely unexplained and all they do in the paper is some statistics voodoo to get some nice looking numbers out of this mess.

  • I thought the science was settled on Newton's laws...

    • Re:I thought... (Score:5, Informative)

      by imadeyoureadpoop ( 4313989 ) on Monday November 07, 2016 @11:57PM (#53234821)

      I thought the science was settled on Newton's laws...

      First rule of science: Science doesn't settle

      • First rule of science: Science doesn't settle

        Unless it's global warming. Then if you don't agree that the science is settled it's

        Silence ... I kill you

    • I thought the science was settled on Newton's laws...

      Is this post from 1905?

    • Casimir effect (Score:5, Informative)

      by Okian Warrior ( 537106 ) on Tuesday November 08, 2016 @12:28AM (#53234927) Homepage Journal

      I thought the science was settled on Newton's laws...

      Firstly, Newton's laws are based on observation and assumptions.

      The observations gives us formulas that seem to fit, but there's no guarantee that those formulas describe all situations in the universe.

      The assumptions, from Noether's theorem stating that symmetries imply conservation laws, are that the universe is smooth, in the mathematical sense of smooth being that space is infinitely divisible. We know that last part isn't true: you cannot measure position to an arbitrary precision in the universe.

      It is therefore seen that Newton's laws become increasingly inaccurate when the scale is very large (relativity), or very small (quantum mechanics).

      You might check out the Casimir effect [wikipedia.org] some time.

      It's not predicted by Newton's laws, but measurable and predictable using QM.

      Anyone who says "EM drive cannot work because it violates my understanding of physics" should really check out the Casimir effect.

      If your understanding of physics does not predict the Casimir effect, you probably shouldn't be commenting on the EM drive, or results from NASA rocket scientists.

      • Re:Casimir effect (Score:5, Insightful)

        by iris-n ( 1276146 ) on Tuesday November 08, 2016 @04:32AM (#53235453)

        This is ridiculous. Conservation of momentum is valid in both quantum field theory and general relativity, there are an appropriate versions of Noether's theorem for them. And I don't see why are you harking about the Casimir effect: it doesn't violate conservation of momentum either.

        Your suggestion that conservation of momentum might fail because of some fundamental discretization of space is also insane: first of all this is just speculative physics at this stage. Second, everyone that does speculate about it agrees that to probe the existence of this discretization would require particle collisions with energy around the Planck energy, about 10^28 eV. For comparison, the maximum we can do now, in the LHC, is to collide particles with energy of 10^13 eV.

        To think that some lame tabletop experiment using only classical electrodynamics, running at most at 80 watts, somehow magically found a way to probe phenomena from an energy scale 15 orders of magnitude larger than the LHC scale, just shows a complete lack of knowledge of all the science involved. At the very least, it would show that the whole particle physics community are complete idiots for spending billions of euros in the LHC, while even more revolutionary science could by done on spare change by Eagleworks.

        • by Roger W Moore ( 538166 ) on Tuesday November 08, 2016 @06:51AM (#53235837) Journal

          Second, everyone that does speculate about it agrees that to probe the existence of this discretization would require particle collisions with energy around the Planck energy, about 10^28 eV.

          That's a rather strong statement considering that there are groups on ATLAS and CMS looking for evidence of Large Extra Dimensions which would reduce the energy scale for this to a few tens of TeV. Personally I don't think they will find anything but certainly they are clearly speculating about it at far lower energy scales.

          To think that some lame tabletop experiment using only classical electrodynamics, running at most at 80 watts, somehow magically found a way to probe phenomena from an energy scale 15 orders of magnitude larger than the LHC scale, just shows a complete lack of knowledge of all the science involved.

          Unfortunately again this is not really a correct thing to say because there are such experiments [wikipedia.org] hunting for axion models of Dark Matter. The LHC is one way to get at high energy physics that is almost guaranteed to find new physics in our energy reach so it is worth the huge cost. However this does not rule out others trying lower budget approaches which can afford to be riskier and to only probe certain models. It is worth remembering that only a few years ago the Nobel prize was awarded to a group which essentially used scotch tape to separate graphite layers something which far more expensive approaches had failed to do.

          • by iris-n ( 1276146 ) on Tuesday November 08, 2016 @07:06AM (#53235881)

            Separating graphite layers does not contradict our basic understanding of physics. I don't have any problem with doing it with scotch tape. Ditto for hunting axions: it is an extension of known theories, not a breakdown of our fundamental theories (that is speculated to happen at high energies). But even hunting axions is already much harder than building this stupid EM drive: they had to make a very specialized very sensitive apparatus, for the simple reason that if axions were easy to detect they would have already been detected.

            Large Extra Dimensions, on the other hand, is another story: there is no half-way decent theoretical model that predicts them, they are just pure speculation. And they were predict to show up at the LHC scale, with the prediction now changed to just above LHC scale, since they did not show up. And doing that is free, since there is no model to build, you just need to throw some numbers in the air.

            Contrast this with fundamental discretization, which is expected to happen for good theoretical reasons, and there are actually some speculative theories (string theory and loop quantum gravity) that implement it.

    • It's not so much newtons laws per se, but energy and momentum conservation laws which are a consequence of very fundamental symmetry laws. See Noether's theorem. That's why physicists have very hard time buying anything that violates these very fundamental principles.

      • t's not so much newtons laws per se, but energy and momentum conservation laws which are a consequence of very fundamental symmetry laws.

        1. The EM Can't Call It A Drive In Good Conscience Yet consumes energy.
        2. Photons have momentum.

        But yeah, it's still very hard to believe.

  • 1/3 lightspeed (Score:5, Interesting)

    by Anonymous Coward on Monday November 07, 2016 @11:49PM (#53234785)

    Ran some numbers. Assuming the power generator and thruster itself has zero mass (obviously not, but it lets us set an upper limit), the energy available in 1kg of U235, at 1.2 millinewtons/kw, would accelerate that 1 kg mass to about 0.35 C, over the course of about 1000 days.

    Add in mass of ship, generators and thrusters and you're looking at considerably less acceleration and top speed, but if this thing works at all (a big IF, granted), manned starships are just within the range of possibility. It'd still be a multi-year (probably multi-decade) trip, but hey.

    • Actually, 0.043 c (Score:5, Informative)

      by bwoneill ( 1973028 ) on Tuesday November 08, 2016 @04:32AM (#53235455)

      I believe your math is wrong. U235 releases 202.5 MeV per atom undergoing fission, so that means 1 kg can generate 83.14 TJ from fission [wikipedia.org]. Assuming 100% efficiency, a massless drive, and no mass loss from propellants, that means there is enough energy from fission to reach a velocity of 0.043 c relative to the rest frame.

      dE = (m - m') c^2 = m' c^2 (gamma - 1) => m' c^2 = m c^2 (1 - dE/(m c^2)) = m c^2 (1 - rho)

      rho = dE/(m c^2) = 83.14 TJ / 89.88 PJ = 9.25e-4

      rho = (1 - rho) (gamma - 1) => gamma = 1/(1 - rho) = 1/sqrt(1 - beta^2)

      (1 - rho)^2 = 1 - beta^2 => beta^2 = rho (2 - rho) = 1.85e-3

      beta = sqrt(rho (2 - rho)) = 0.0430

  • by dunkindave ( 1801608 ) on Tuesday November 08, 2016 @12:26AM (#53234923)
    And if they pump in 1.21 Gigawatts, they're going to see some serious shit!
  • Can someone clued up here, please explain to me more about the figures of this thing in regards to propulsion?

    It's obviously generating very little propulsion, but it's "free" if electricity is free, right?
    So if we had a massive reactor shoveling power into it, would it generate more, or the device need to be larger or we need more of them?

    Could we build a ship with the existing one, assume again unlimited power reactor somehow and then fire the thing up, would I be right in thinking this thing would incred

    • It's usefulness as a propulsion device remains to be seen.

      First, it may ultimately be determined to be the result of experimental errors or failure to account for various effects. Good science, but boring outcome.

      Or it may be found to work, and be proven to be exploiting some currently unknown or poorly understood area of physics. Understanding then how it works and how it produces its force will lead to potential useful applications. If it's understood how it works its possible one could be designed to hav

    • I get the no fuel and I get the very little force but I can't imagine the implications for it.

      A slow, steady thrust. In the vacuum of space, there's no thrust wasted to keep you at speed, like flying in the atmosphere. Over time, even a tiny thrust can build you up to phenomenal speeds. Just make sure you turn your engine around and start to slow down at the halfway point of your journey.

      • by Tablizer ( 95088 )

        Over time, even a tiny thrust can build you up to phenomenal speeds.

        That's why it's so hard to test, YET so enticing at the same time.

        There may indeed be a very minor oddity, in terms of effect, in quantum physics that we haven't discovered yet that allows the phenomenon without throwing out all prior knowledge. We just may be applying existing knowledge wrong, assuming a spherical cow somewhere when it's really an octahedron or the like.

        I'm at a loss to think of something from technological history that i

        • I'm at a loss to think of something from technological history that is comparable to this possibility: something that didn't seen possible or feasible under the known laws of physics or nature, but turned out to actually "fly".

          The laser perhaps? I don't think it could be conceived of until Einstein.

          https://en.wikipedia.org/wiki/... [wikipedia.org]

          The difference with this discovery (if true) is that Einstein laid the theoretical framework and then the laser was built 43 years later (36 years for the maser) while in this cas

    • by raymorris ( 2726007 ) on Tuesday November 08, 2016 @01:44AM (#53235127) Journal

      I'm no physicist myself, and physicists don't understand this thing anyway, but here's my understanding:

      Yes, appears that the only input is electricity, and it seems to produce thrust. So if electricity is free, a tiny amount of thrust is free. I say it APPEARS that the only input is electricity- many reactions which we now understand include oxygen from ambient air as an input, and that might have easily go unnoticed in an experiment before the reaction was understood. Similarly, it's possible that this thruster is using some non-obvious input, such as ambient radiation.

      We don't know if one could be built much larger, or what the current capacity is for a given size. Maybe a 100,000 watt one could be small, maybe it would need to be very large. Maybe it would be far more efficient, maybe far less. We're still trying to confirm that the thing works at all.

      > would I be right in thinking this thing would incredibly slowly start moving the ship and over a ridiculous amount of time, eventually be moving very rapidly and in theory (?) just keep on accelerating?

      Yes, in theory, up to near the speed of light. Or maybe not. 1500 years ago someone discovered that if you burned charcoal mixed with livestock poop in a bamboo shoot, you got a similarly weak thrust. Later we figured out it was the dried pee, not the poop, that mattered and adding sulfur helped. So a thousand years ago they had black powder rockets, which kept accelerating through the air as long as the engine kept burning. Now we know that a rocket won't keep accelerating forever in air, but it took a thousand years to figure that out. We're still in the "poop in a tube" stage of EM drives, so we really don't know what the potential is.

      • by serviscope_minor ( 664417 ) on Tuesday November 08, 2016 @05:19AM (#53235593) Journal

        Or maybe not. 1500 years ago someone discovered that if you burned charcoal mixed with livestock poop in a bamboo shoot, you got a similarly weak thrust. ... We're still in the "poop in a tube" stage of EM drives, so we really don't know what the potential is.

        1,500 years ago people also discovered (repeatedly) how to turn base matals into gold, that draining one of the humours fixed the disease causing that humour and that barnacle geese hatched from barnacles attached to driftwood.

        We're not at the poop-in-a-tube stage of the EM drive, we're at the leeches to drain blood stage.

        • Btw you know we actually have medical leaches and use them after surgeries like finger reattachment?

    • The practical implication is that if such reactionless drives are possible, the spacecraft will still need to carry a power source to run it, but not the huge masses of fuel to be spewed out the back to provide Newton's "equal but opposite reaction".

      This is a technology that you hope for (new physics) but bet against (conservation of momentum). Very telling in the Wikipedia writeup is that one proponent got thrust in all of 7 tests - but 4 were in one direction and 3 in the opposite direction. This strong

  • I think the next logical step is to test "fire" an EM drive in the vacuum of space and see if it is still producing thrust when moving around the earth in both zero gravity and zero atmospheres.

    A positive (speaking) result in that instance would go a long way to proving whether or not it was capable of driving future space exploration

    • I think the next logical step is to test "fire" an EM drive in the vacuum of space and see if it is still producing thrust when moving around the earth in both zero gravity and zero atmospheres.

      A positive (speaking) result in that instance would go a long way to proving whether or not it was capable of driving future space exploration

      Problem is, that requires a pretty big cash investment just to test an unproven and scientifically dubious technology.

  • by slashmydots ( 2189826 ) on Tuesday November 08, 2016 @12:12PM (#53238067)
    Scientists claim to be all about logic and reason and testing and evidence and then they deny something when it's right in front of their face because it doesn't mesh with what can only be called their particular belief system. Absolute lunacy.

Philosophy: A route of many roads leading from nowhere to nothing. -- Ambrose Bierce

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