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NASA Space

NASA's Impossible Propulsion EmDrive Is Heading to Space (popularmechanics.com) 248

An anonymous reader writes:The EmDrive, a hypothetical miracle propulsion system for outer space, has been sparking heated arguments for years. Now, Guido Fetta plans to settle the argument about reactionless space drives for once and for all by sending one into space to prove that it really generates thrust without exhaust. Even if mainstream scientists say this is impossible. Fetta is CEO of Cannae Inc, and inventor of the Cannae Drive. His creation is related to the EmDrive first demonstrated by British engineer Roger Shawyer in 2003. Both are closed systems filled with microwaves with no exhaust, yet which the inventors claim do produce thrust. There is no accepted theory of how this might work. Shawyer claims that relativistic effects produce different radiation pressures at the two ends of the drive, leading to a net force. Fetta pursues a similar idea involving Lorentz (electromagnetic) forces. NASA researchers have suggested that the drive is actually pushing against "quantum vacuum virtual plasma" of particles that shift in and out of existence. Most physicists believe these far-out systems cannot work and that their potential benefits, such as getting to Mars in ten weeks, are illusory. After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards. Yet the drumbeat goes on. Just last month, Jose Rodal claimed on the NASA Spaceflight forum that a NASA paper, "Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum" has finally been peer-reviewed and accepted for publication by the American Institute of Aeronautics and Astronautics, but this cannot be confirmed yet.
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NASA's Impossible Propulsion EmDrive Is Heading to Space

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  • by wierd_w ( 1375923 ) on Friday September 02, 2016 @07:39PM (#52818587)

    Even if he sends this to space, the argument that it is leaking evaporated bits from the interior of the cavity will persist.

    I expect others to follow.

    Until he sends the damned thing on a tour of the solar system with no other forms of propulsion, where any such arguments would require the evaporation of significant portions of the cavity internals, and where both speedup and slowdowns happen, this will never be settled.

    • by 93 Escort Wagon ( 326346 ) on Friday September 02, 2016 @08:07PM (#52818729)

      Does it count as an argument if I point out that the titular claim is full of hot air?

      The guy behind the idea has (at least according to himself) formed a company with the stated goal of getting this thing into space. There's no scheduled launch in place yet, nor any specific plan. No mention of funding either, although a different guy is apparently launching a Kickstarter to get his own version into space. Don't worry, if it never goes I'm sure he'll spend the money wisely.

      Right now it's all hand-waving, which means the concept is at pretty much the same place it's always been.

    • It seems to me this is indeed the infinite improbability drive. If it actually propels something doe we care why?

      • by argumentsockpuppet ( 4374943 ) on Friday September 02, 2016 @09:11PM (#52819055)


        We care a lot. If something doesn't follow the laws of physics as we know them, that means that either we don't understand the something or there is something we don't understand about the laws of physics.

        If we don't understand what is happening to something and we figure it out, that's useful engineering knowledge.

        That's actually the less awesome potential. If we don't understand something about the laws of physics and we can figure that out instead... well that changes the world. It makes possible what we think impossible.

        If an alien landed a spaceship in the middle of Times Square, it wouldn't necessarily change our understanding of physics. This could.

        • by kuzb ( 724081 )

          This is exactly right. And even if it is found to be bunk, that's still useful information because we will have learned a new way to test such claims. So whether it is what it claims, or it isn't what it claims, it still has a measure of scientific value if you can properly test it.

      • by Jeremi ( 14640 )

        It seems to me this is indeed the infinite improbability drive. If it actually propels something do we care why?

        You'll care why after it turns you into a teacup...

        • Re: (Score:3, Informative)

          by JaiWing ( 469698 )

          a bowl of petunias and a very surprised looking whale....

          i wonder if it will be friends with me? ...
          - Douglass Adams RIP

          • a bowl of petunias and a very surprised looking whale....

            i wonder if it will be friends with me? ...
            - Douglass Adams RIP

            Oh, no. Not again.

    • by arpad1 ( 458649 ) on Friday September 02, 2016 @11:17PM (#52819563)

      First off, if the engineers designing this thing are remotely competent there won't be any out-gassing.

      Uncontrolled out-gassing is, and has since the beginning of the space age, been a really obvious problem. So it'll be designed from the get-go to avoid uncontrolled out-gassing.

      It also doesn't have to be brought back to Earth to be weighed. Acceleration, if any occurs, can be measured pretty precisely. The degree of acceleration is a product of the mass and velocity of out-gassing.

      If there is any observed acceleration you just have to wait until the amount of reaction mass necessary to account for that acceleration exceeds some reasonable amount and we're done - it works. No tour of the solar system necessary.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      It either works or it doesn't. Honestly: it is irrelevant if humans understand it. Shoot one up there. It's VERY cheap (compared to bank bailouts and wars). Run it. See if it works. This is not rocket science. Okay, so it's rocket science. But it should be fairly obvious. Shoot it up there, and watch it.

    • by gweihir ( 88907 )

      For people with some actual understanding of Science, with has long hence been settled. Extraordinary claims need extraordinary proof. At this time these people struggle to provide even regular proof.

      But here is a thought: Sent it to space, power it with the Rossi E-Cat, and sent the whole thing on a course into the sun!

  • Before any else. Flux capacitor. Now.. on to conversation with some utility...

  • by Dusty101 ( 765661 ) on Friday September 02, 2016 @07:45PM (#52818615)

    ... or can ye?

    • by barc0001 ( 173002 ) on Friday September 02, 2016 @07:51PM (#52818643)

      Nope, you can't. However, what's to day we *know* all of them yet? If he's right and this works, then it means we have to examine why it does and possibly adjust our understanding to date. If it doesn't, carry on as usual.

      • by rubycodez ( 864176 ) on Friday September 02, 2016 @10:05PM (#52819285)

        yes, we can. The "laws of physics" are man made and have been changed before. They are models of reality with varying degrees of usefulness.

        • The "laws of physics" are man made and have been changed before.

          Actually I would claim that most physicists view the "laws of physics" as the fundamental properties and behaviour of the universe and the energy and matter it contains. Our understanding of these laws (the human laws of physics if you like) is imperfect and has certainly changed in the past but, so far as we are aware, the laws of physics themselves are constant.

          However that does not rule out the possibility that at some point in the future we might be able to change them. Since they are a property of

  • by JoshuaZ ( 1134087 ) on Friday September 02, 2016 @07:51PM (#52818639) Homepage
    At this point, it seems that what is happening is a combination of two factors: 1) Experimental error. 2) Small amounts of material are being heated up and outgassed. This is consistent with an open cavity and is consistent with some of the reports having the drive's thrust take a small amount of time to start off, which looks a lot like it is taking time for the cavity to heat up.
    • by wierd_w ( 1375923 ) on Friday September 02, 2016 @08:12PM (#52818745)

      That is why i said it needs to go on a little cruise.

      Say. A lap up to and back from lunar orbit. A distance that is still both close enough to closely monitor the test article, and far enough that if it were using evaporated cavity materials as reaction mass, the entire test article would need to be consumed.

      It is otherwise impossible to rule out what you suggest: it may well be happening, but that kind of issue would be insufficient to satisfy the reaction mass requirements of the proposed test. A successful completion wouldnt rule out vapor release, it wiuld just show it does not dominate the generated thrust. Until a result that can only happen if reactionless drive is produced, and in a big way like that, the argument that there is reaction mass, and that it dominates the recorded thrust will never die.

      • If it can extend the orbit of the satellite from weeks to months as is the stated plan, then it would become commercially valuable whether or not it's truly reactionless. I very much doubt it will do so, but if he's not trying to make somebody else pay for it then great.

      • by gweihir ( 88907 )

        And what you say is wrong. The thrust generated is far too small for that. If you, say , power this thing with a radio-thermal generator, this generator would already generate more thrust from its thermal radiation.

    • by gweihir ( 88907 )

      And for anybody with some actual understanding of Science, this is already by far enough to lose interest. The thrust observed is very close to the error margins that are obvious and a good scientists does one thing in that case: Look for additional sources of errors. They do not claim what these frauds here claim.

    • I find this excerpt from the NASA report [nasa.gov] to be the most telling. (Emphasis mine.)

      Thrust was observed on both test articles, even though one of the test articles was designed with the expectation that it would not produce thrust. Specifically, one test article contained internal physical modifications that were designed to produce thrust, while the other did not (with the latter being referred to as the "null" test article).

      So, they tested the real drive, and a dummy fake drive, and measured thrust for both

      • by Megol ( 3135005 )

        *SIGH* No that's not what they say nor what they meant. The null device in this case were identical to the other _except_ it didn't contain internal elements that the Cannea drive theory claimed was essential for functions. In other words what the test showed was that those internal elements weren't necessary for the function of the unit, nothing more - nothing less.

        This "dummy drive measured thrust" idea is common among anti-Em drive people. Or in other words they doesn't even bother to read the report bef

        • the null device in this case were identical to the other _except_ it didn't contain internal elements that the Cannea drive theory claimed was essential for functions. In other words what the test showed was that those internal elements weren't necessary for the function of the unit, nothing more - nothing less.

          So whoever or whatever Cannea is or are doesn't know how this divice works- if indeed it does work.

          If one of the promoters is keen to pay - from their own pockets, or from their investors pockets -

  • Can we all just take a moment to acknowledge how awesome Guido Fetta's name is?

  • by Anonymous Coward on Friday September 02, 2016 @08:04PM (#52818709)

    The laws of physics have changed so much in the last few thousand years, why do we suddenly think we are at the pinnacle of dictating the laws that govern the universe just because we haven't found anything contrary in the last few hundred years? Our laws of physics are based around our extremely limited observation of a tiny portion of the universe; surely when more is observed then some of the laws are going to change.

    Science relies on an open mind and proof of a theory by repeatable experimentation so all the naysayers who instantly dismiss anything with even the remotest possibility of redefining one of these laws of physics cannot be truly called scientists and are no better than those that would dismiss the notion of there being no god just as easily.

    • Laws of physics aren't usually found to be wrong, they are just improved when new cases that haven't been previously considered are discovered. For instance Einstein didn't show that Newton was wrong, he just found that Newton's laws didn't work well for extremely high speeds. You'll note that Newton's math still works just as well as Einstein's does for almost all terrestrial applications.

      • They're not usually found to be wrong, but...the luminiferous aether [wikipedia.org] would like a quick word with you.

        • Even the aether wasn't entirely wrong. The wave-in-a-medium model of light explained a lot of things very well. Interference. Refraction, including variable refraction according to frequency, seemingly constant speed. The aether part was wrong, but it was only one component of the model, and the model in general was pretty good.

    • Science relies on an open mind

      That definition doesn't fit any of the modern scientists I have read about, across a number of fields.

      I thought the new way was to have a preconceived notion and bake your data to make it fit, or else just write so thickly the reader will think up is down by the end.

      You can bet a lot of new interesting discoveries are being swept under the rug by people scoffing just as they did for the EM drive because they didn't believe something was possible.

    • Scientists spend lots of time trying to find ways in which our current understanding of physics is wrong. This is generally done by doing measurements that are in some way fundamentally new: new conditions, higher accuracy experiments, measuring new things. LHC looks at interactions at very high energy. Low temperature experiments look for unexpected effects at extremely low energies. Astrophysical measurements look at effects in very strong gravity, or very large distances.

      Electromagnetism has been meas

    • You are right! Why, just last week the Laws of Conservation of Energy changed 3 times! Fucking idiots. The laws this thing is violating has never changed. You stupid people with your ecats, emdrives, timecubes need to just shut up and attend a Physics class.
  • Exhaust based systems are so 1960's anyway...

  • by ffkom ( 3519199 ) on Friday September 02, 2016 @08:20PM (#52818795)
    The press hype goes on despite results of two experimental results that clearly indicated the mythical drive to not thrust: A group of physicists at the university of Dresden measured miniscule thrust, but strangely enough the thrust went into the same direction when the "EMdrive" was rotated by 90. So they figured that what they measured was probably resulting from an interaction of the electric powering from the outside with the magnetic field of earth. They couldn't easily remove this probable source of error in their setup, but a chinese group of physicists managed to do so: They powered the "EM-drive" from a battery that was within the same enclosure - and voila - no more thrust to be measured.
    • Papers?

    • by afxgrin ( 208686 )

      > powering from the outside with the magnetic field of earth

      nah quite certain it's just the presence of the electric field from the magnetron source screwing up all their readings. Once you start messing around with >100W magnetron sources the presence of electric fields will show a voltage reading on just about any voltmeter or any sort of voltage measurement device. You need to spend considerable effort to shield all these potential false signal sources.

      If you want a simple example, by pass the i

      • "a lot of additional letters after a person's name means almost nothing to me now." I resemble that remark! Mo' betta you no talk stink, eh?

  • This paper has a possible explanation that was ignored by the article. If the EMDrive works, then the same explanation likely also applies to some of the galactic rotational observations that are used to justify the need for dark matter.

    http://arxiv.org/pdf/1604.0344... [arxiv.org]

  • Language prejudice (Score:5, Insightful)

    by n3r0.m4dski11z ( 447312 ) on Friday September 02, 2016 @08:48PM (#52818949) Homepage Journal

    "After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards. "

    Good thing it's not a rocket then.

  • After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards.

    Perhaps it's more of a guideline.

  • Finally. This is the real test. I suggest they put a radio beacon on it that any ham can receive. Either the signal triangulates further and further away and fades, or it doesn't. Of course some people will never believe, and others will always try even if the thing remains mired in LEO, spirals in and burns up; but this needs to be done.

  • It's not NASA's (Score:5, Informative)

    by wonkey_monkey ( 2592601 ) on Friday September 02, 2016 @08:57PM (#52818995) Homepage

    NASA's Impossible Propulsion EmDrive Is Heading to Space

    It's not NASA's.

  • NASA's Impossible Propulsion EmDrive ...

    The output of which would be the Impossible Propulsion Force. Tom Cruise is ready and waiting.

  • ... of the trillions of endless assertions on the internet which neither create any nor meet any equal and opposite force, since they have no causal effect on reality. To resolve this discrepancy of pent-up psychodimensional energy, the universe has willed into existence such a drive tapping into a transdimensional energy portal releasing the pent-up energy of those assertions, thereby preventing a massive buildup which would eventually cause such a huge catastrophic explosion so as to render reality as we

  • by dbreeze ( 228599 ) on Friday September 02, 2016 @10:35PM (#52819389)

    Not all observable, repeatable phenomena can be explained yet. The random formation of DNA seemingly defies statistical probability, yet, it happened. Just sayin' here...

  • Can you fit "NASA" in the summary a little more, you fucking crackpot submitter? This is a stupid hoax. This isn't NASA. This is just some guy who rented a NASA lab space. Anyone can do that. Just stop. Stupid Space Nutters.
  • I suspect this will turn out not to work. That said, it did remind me of the New York Times article in 1920 saying that Robert Goddard was foolish to think that rockets could work in space (see e.g. http://www.popsci.com/military... [popsci.com] for their 1969 retraction).