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German Scientists Confirm NASA's Controversial EM Drive
MarkWhittington writes: Hacked Magazine reported that a group of German scientists believe that they have confirmed that the EM Drive, the propulsion device that uses microwaves rather than rocket fuel, provides thrust. The experimental results are being presented at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando by Martin Tajmar, a professor and chair for Space Systems at the Dresden University of Technology. Tajmar has an interest in exotic propulsion methods, including one concept using "negative matter."
Well NADA is an unlikely source for scams and it doesn't fit the pattern. The science behind it is openly shared without any secret sauce claims. The physics are uncontroversial.
The only thing there could be scam in is whether our engineering can really cash in on it.
At it's best its also not claimed to provide much thrust. You can't leave earth with it. But once you do even a tiny bit of thrust goes a long way. It's not even the only known way to get thrust without fuel - solar sails do that too.
I never got why so many people are so sceptical of this one. Engineering scams are nothing new but this breaks every pattern and the science is genuinely sound.
Unicode killed the ASCII-art *
What more do I need to say?
I'm very hopeful this works. It's easy to be cynical, so I won't say "meh it's all bullshit!" Still, I won't be convinced until I see it provide thrust in a vacuum, away from Earth's magnetic field. It's still far, far too likely it's pushing off something terrestrial. So I'll give them a healthy "go, team, go!"
That said, quoth the article:
"This is the first time that someone with a well-equipped lab and a strong background in tracking experimental error has been involved, rather than engineers who may be unconsciously influenced by a desire to see it work," notes Wired referring to Tajmar's work.
I don't know about that. He is a real professor at a real university, but he also has filed for a patent on a gravity generator, using a process no one has duplicated. Somebody who thinks they've got a gravity generator, but gosh just can't prove it to everybody else, is definitely somebody who may be "unconsciously influenced by a desire to see it work."
We don't have a state-run media we have a media-run state.
In the conclusion section:
The nature of the thrusts observed is still unclear. Additional tests need to be carried out to study the magnetic
interaction of the power feeding lines used for the liquid metal contacts. Our test campaign can not confirm or refute
the claims of the EMDrive but intends to independently assess possible side-effects in the measurements methods
used so far. Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating
many possible error sources that should warrant further investigation into the phenomena. Next steps include better
magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that
allow tuning for optimal operation. As a worst case we may find how to effectively shield thrust balances from
magnetic fields.
Ahem ... that would be an _ostensible_ propulsion device, the working principle for which is (according to mainstream physicists) poorly described and violates commonly accepted physical principles. OTOH, I hope it works. I'll believe it when they cram a couple of megawatts in, and get it to lift its own weight - or better, 100 times its own weight.
I note that the Dr. Tajmar, the researcher whose name is on the paper, is still using terms like "... if true ...". This is not yet a tried-and-true propulsion device. The articles I saw just now did not show actual numbers, but the NASA experiment used such low power that the apparent thrust was well below several of the potentially confounding effects; i.e. the noise was much higher than the signal. It may still turn out to be the result of some experimental error, an unexpected issue with the apparatus, etc. Again though, one hopes. :)
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
something with a very long, low-thrust burn such as DS1's ion propulsion* and enough fuel to run for half a century maybe, Voyager 1 left the Sun's influence last year - nothing launched from Earth will ever catch it using gravity assists. New Horizons might be travelling at twice the speed of Voyager right now but it's not even 40AU out, by the time it gets to apoapse it'll be travelling slow enough to drop back - it's in a 100AU heliocentric orbit.
*the Dawn spacecraft, currently in orbit around Ceres, also uses ion propulsion - the same NSTAR 2100W engine as DS1, in fact.
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Tajmar made a lot of hoopla over ten years ago about making gravitomagnetic waves orders of magnitude more powerful than GR predicted; some were claiming we were on our way to artificial gravity or a warp drive by his bold claims. Of course, his experiments could never be duplicated. Since then, he's been trying to make waves (ha!) with other dubious claims of making gravity effects by electromagnetic means and such.
Take anything he claims "confirmed" with a one hundred pound bag pinch of salt.
Ion thrusters still consume raw materials, so there's a finite fuel supply. If this does literally turn electricity into thrust without consuming anything then running out of reaction-mass is no longer an issue, and some probes could even be entirely solar powered.
Do not look into laser with remaining eye.
Neither Newton's nor Einstein's theory of gravitation were greeted with "extreme skepticism" by the general community.
Note, for the record, that an ion thruster IS a rocket - it shoots mass out the back (ions, in this case, accelerated electricly) just like any other rocket.
Note that if this EM drive pushes photons out the back, it is also a rocket. However, what I've read on the subject says it doesn't push photons out the back (not even microwave photons), so it's either something unexpected, or a huge steaming pile.
I'll be interested in the first deep-space probe built to test this thing. Should be simple enough - solar panels for power, EM-Drive for push, a comm-channel or six, and something to announce its presence, so we can determine its velocity relative to Earth at all times. If it accelerates, we win. If not, we wasted the cost of a (small) satellite....
"I do not agree with what you say, but I will defend to the death your right to say it"
Of course they do. Ions are simply an atom that has either gained or lost electrons and now has a net electric charge, either (+) or (-). As such, they are made up of protons, neutrons and electrons, all of which have mass.
Bad example. Light does exert radiation pressure, yes - but it is far, far too weak to drive a radiometer. The spinning radiometer isn't due to radiation pressure. It's a more mundane effect: Imperfect vacuum. The black side is warmed more than the white, which heats up adjacent air, which exerts higher pressure, causing the spin. It's just a plain old heat engine.
An ion thruster is a very efficient reaction mass based thruster,
It still has to drag all that reaction mass along, despite it's only real purpose being that it's thrown out like garbage just to provide thrust.
It takes thrust to push that reaction mass around the place, up until you actually throw it out the window, which is actually out the directed nozzle or whatever.
And what happens when you run out of reaction mass? You have no more thrust.
On the other hand, if you have a reactionless thruster, as long as you provide it with power, it will give you thrust. Slap on solar panels, or if it's a deep space mission, nuclear batteries or the like, and you are set.
As an added bonus, you can use that constant acceleration trick to really build up some speed. Something you can't do with reaction mass because you don't ever have enough, even for a tiny trip like to the moon.
The physics are most certainly NOT uncontroversial.
If this thing were to truly work, it would have insane implications to some basic assumptions about the universe - namely about the very laws of physics themselves.
This device working means that the laws of physics do vary by translation, which goes against every single other observation ever made. The science behind it is most certainly not clearly sound. Skepticism is the only logical option for this thing.
Scientists Confirm 'Impossible' EM Drive Propulsion
Science News, Space / July 27, 2015 / by Giulio Prisco/
Later today, July 27, German scientists will present new experimental results on the controversial, "impossible" EM Drive, at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando. The presentation is titled "Direct Thrust Measurements of an EmDrive and Evaluation of Possible Side-Effects."
Presenter Martin Tajmar is a professor and chair for Space Systems at the Dresden University of Technology, interested in space propulsion systems and breakthrough propulsion physics.
A Revolutionary Development for Space Travel
The EM Drive (Electro Magnetic Drive) uses electromagnetic microwave cavities to directly convert electrical energy to thrust without the need to expel any propellant. First proposed by Satellite Propulsion Research, a research company based in the UK founded by aerospace engineer Roger Shawyer, the EM Drive concept was predictably scorned by much of the mainstream research community for allegedly violating the laws of physics, including the conservation of momentum.
However, NASA Eagleworks – an advanced propulsion research group led by Dr. Harold G. “Sonny” White at the Johnson Space Center (JSC) – investigated the EM Drive and presented encouraging test results in 2014 at the 50th Joint Propulsion Conference.
White proposes that the EM Drive’s thrust is due to virtual particles in the quantum vacuum that behave like propellant ions in magneto-hydrodynamical propulsion systems, extracting "fuel" from the very fabric of space-time and eliminating the need to carry propellant. While a number of scientists criticize White's theoretical model, others feel that he is at least pointing to the right direction. The NASASpaceFlight website and forums have emerged as unofficial news source and discussion space for all things related to the EM Drive and related breakthrough space propulsion proposals such as the Cannae Drive.
Shawyer has often been dismissed by the research establishment for not having peer-reviewed scientific publications, but White and Tajmar have impeccable credentials that put them beyond cheap dismissal and scorn. Physics is an experimental science, and the fact that the EM Drive works is confirmed in the lab. "This is the first time that someone with a well-equipped lab and a strong background in tracking experimental error has been involved, rather than engineers who may be unconsciously influenced by a desire to see it work," notes Wired referring to Tajmar's work.
Hacked has obtained a copy of Tajmar's Propulsion and Energy Forum paper, co-authored by G. Fiedler.
"Our measurements reveal thrusts as expected from previous claims after carefully studying thermal and electromagnetic interferences," note the researchers. "If true, this could certainly revolutionize space travel."
"Additional tests need to be carried out to study the magnetic interaction of the power feeding lines used for the liquid metal contacts," conclude the researchers. "Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena. Next steps include better magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that allow tuning for optimal operation."
Contrary to sensationalist reports published by the sensationalist press, the EM Drive is not a "warp drive" for faster than
There's no place I could be, since I've found Serenity...
It cannot be incomplete, it is a purely mathematical statement.
Particularly, for linear momentum, conservation of linear momentum is equivalent to the laws of physics being symmetric by translation.
If linear momentum is not conserved, the laws of physics are not the same throughout the universe and vice-versa.
Thank you for enlightening me. I read the wikipedia page on radiometers: https://en.wikipedia.org/wiki/...
I learned that radiometers do NOT work by "light pressure" which was Crooke's, the inventor's, hypothesis. Radiometers do NOT spin in a perfect vacuum. The two mechanisms that explain why they spin were proposed by the likes of Einstein (relativity guy), Maxwell (equations guy), and Reynolds (number, not aluminum, guy).
Not necessarily. Leading WAGs include that it is thrusting against dark matter or space itself. In those scenarios, momentum is still conserved.
I wrote a comment on this up above, but just to help you understand...
1) No, the ion drive does not use electricity to produce thrust. Ion drives, as their name suggests, use ions to produce thrust. The ions are accelerated using fields generated via electric power, but that's no more a case of using electricity to (directly) produce thrust than an electric car is (the car pushes against the road, imparting momentum to the earth which balances the momentum imparted to the car).
2) Yes, it sounds like a free energy machine. If a given amount of electrical power produces a given thrust, constantly, without consuming any fuel, then you can generate unlimited energy by attaching this thing to a flywheel or rotor arm that drives a generator and it will produce more energy than it requires to drive the thruster. Some of the current theories about this thing claim that it won't do that, that its efficiency will go down the faster it's moving (relative to a given frame of reference).
3) No, electricity is not fuel. Electricity is not a thing. It is a process. Electricity is the motion of electrons. It is a form of energy. Fuel is a way to store energy, but it is not energy itself. You can generate electricity from many things, including fuel, and there are many forms of chemical devices with electrical potential energy - we usually call them batteries - but electricity is not, itself, fuel. Now, the energy still needs to come from somewhere (unless this drive does turn out to be usable to get more energy out than is put in, which would turn *all* of physics on its head) and that "somewhere" is usually fuel of some kind... but it can be things like uranium in a nuclear reactor that is usable for decades from a tiny amount of mass, or hydrogen in the sun producing photons as it fuses and those photons being captured and used to move electrons via the photoelectric effect (in layman's terms, solar panels).
There's no place I could be, since I've found Serenity...
But I'll still be willing to listen to reasonable follow-up experiments instead of dismissing out of hand. So we get to Martin Tajmar and his claims (also not peer reviewed, but at least it's at a conference). Tajmar is not the guy I'd choose as the most reputable source. He has a history of claims about...creative physics from poor experimental setups. That is, he claims to observe new physics, but people have consistently had a hard time reproducing his results. Go ahead and google the guy.
I did, and appearantly it was Martin Tajmar himself, who found the flaw in his gravitational gyroscope thesis, and published it: FiberOpticGyroscope Measurements Close to Rotating Liquid Helium. So whatever you think about the guy, a superficial Google result seems to put him at least as honest. If he makes a mistake, he is able to admit it.
Here is the first page of the actual paper, including the abstract which says:
Our test campaign can not confirm or refute the claims of the EMDrive but intends to independently assess possible side-effects in the measurement methods used so far.
So the /. title says pretty much the exact opposite of what the actual
paper says.
I am still extremely skeptical that there is any actual effect. They powered their device with a 700 watt magnatron and measured plus or minus 20 micro-newtons of thrust. To put this in perspective, one Newton is roughly the weight of an apple near the surface of the Earth. If the thrust scales linearally with input power then you would need 50,000 x 700 Watts = 35 Megawatts to levitate a single apple. Of course the inventor claims that the thrust to power ratio is highly non-linear so at these higher power levels you would get a lot more thrust. I have not seen any sensible theoretical model that explains why this would be so.
If you are using hundreds of watts to produce a handful of micro-newtons then it is extremely likely there is no actual effect and what is being measured is just some form of noise. This is especially true when the so-called effect violates a primary law of physics.
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People are so sceptical of this one because if true the implications are universe-shaking. It would completely overturn not just modern physics but all of physics since Newton. The claim is that the device violates conservation of momentum. Then via Noether's theorem this implies that the laws of physics are not independent of location in space. (Alternatively, the device is creating a beam of hard to detect particles via some completely unknown but low energy mechanism.)
Also, the device was first designed using a provably incorrect analysis - an analysis using standard physics determined that the device would produce thrust without reaction mass, violating conservation of momentum. As all the standard physics used in the analysis conserves momentum, the analysis must be incorrect. If someone adds up many even numbers and comes up with an odd total, we know they have made a mistake, even without examining their calculations to find out where. This case is exactly analogous. So if this device really does violate momentum conservation, it is a complete and utter fluke, and not by design.
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Looking at this another way:
When LHC were looking for the Higgs boson - a particle entirely expected by modern physics - they required a five sigma signal before they were satisfied that they had really found something.
This is a result not only entirely unexpected, but contradictory to almost all known physics. A two sigma (NASA) and three sigma (Germany) signal is not remotely enough to be convincing. At best it is convincing enough for someone to spend the money to further and better test it.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
There was a similar set of claims roughly 60 years ago for the "Dean Drive" a "reactionless drive" that did not seem to use propellant. To casual review, and letting it push your hand, it seemed to work, and a great campaign for research and to ignore the sceptics of the time was headed by John W. Campbell, the editor of Analog magazine. Analog was, and remains, a science fiction magazine specializing in hard science and science fiction based on it, and it had many real scientists as readers and contributors, so the Dean Drive received quite a lot of attention.
The Dean Drive has since been pretty thoroughly debunked as an "oscillation thruster", a device that relies on tuned "slipping" on the floor it rests on to creep forward and even to provide a modest thrust, _pushing against the floor_. The designer was never willing to allow a full "pendulum" test, or careful testing outside of his own workshop, and there seem to be dozens more of similarly patented "reactonless drives". The ones that work at all also seem to be "isicllation thrusters", pushing against the floor or the mehanism in which they are mounted.
Except it doesn't. The microwaves are not emitted anywhere. They are generated into a sealed chamber. There's nowhere they can go.
The formulae you listed would be useful to describe thrust from a photon drive (or light drive), but those need an open-ended emitter. Also, the results you get from them are about three orders of magnitude too low for the observed ratio of thrust to power. A 700W microwave photon drive wouldn't be detectable by the experimental apparatus.
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Photons have no rest mass. Their mass is entirely their energy. They do have mass.
This isn't new. They had to correct for Pioneers microwave thrust. Heat thrust is the accepted explanation for the Pioneer anomaly.
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Every post here are ignoring that there's THREE types of engines they are talking about. An ion thruster has reaction mass and expels atoms rearwards, i.e. solid fuel. It may be able to scoop this fuel up, but yeah, it's a standard engine.
A photonic rocket does not use reaction mass, and expels massless photons, i.e. radiation. You simply heat something, and the heat emissions generate opposite thrust. This generates thrust as photons lack mass but do have momentum, relating to the Planck length. The problem with photonic rockets is that this is REALLY REALLY LOW. Quoting Wikipedia: "If a photon rocket begins its journey in low earth orbit, then one year of thrusting may be required to achieve an earth escape velocity of 11.2 km/s if the vehicle is already in orbit at a velocity of 9,100 m/s"
The EMdrive does not require reaction mass, and simply expels microwaves which are kept in a resonant mode inside a chamber made of copper. The theory is that they basically push against _something_ like irregularities in space, or a virtual quantum plasma, or whatever. Remember that the casimir effect is already mainstream science - pairs of virtual particles appear and disappear - so there's at least something weird with space itiself. But anyway, it's similar to a photonic rocket in that it doesn't use reaction mass, but far, far more efficient and thrust-generative based on early signs.
> The science behind it is openly shared without any secret sauce claims.
There is no 'science behind it'. At best there's some experimental data which is probably measurement error or a mundane effect that isn't being considered.
> the science is genuinely sound.
Actually, the claim of "thrust without reaction mass" is not only unsound, it's so far off the scientific deep end that it boggles the mind. You may not need to carry any propellant for this engine to work, but you sure as heck need to carry tons of LSD to keep it working.
> It's not even the only known way to get thrust without fuel - solar sails do that too.
Solar sails use reaction mass. They just don't store it on board.
> Engineering scams are nothing new but this breaks every pattern
It doesn't fit the pattern of 'scam', true. It does, though, fit the pattern of 'hopeless optimism getting in the way of actual science.'
A fool and his hard drive are soon parted.
> Modern physics is never incorrect.
And you, sir, have just turned science into religion.
The whole reason science is superior to religion is that it openly admits that it may be incorrect, and allows for itself to be corrected. It is, as you correctly outline, an iterative process that approaches truth over time. But part of that process is accepting that any truth may be overturned by new evidence. And while Einstein didn't "disprove" Newton, he did show flaws in the theory which meant that it was, in a very small way, wrong. And that's fine. Claiming it was "extended" and not "wrong" is playing semantics and makes you sound like a religious apologist.
The more comfortable we are with being wrong, and the process of refinement, the better scientists we are. The more we claim that some aspect of science is "never incorrect", the more dogmatic we are and the science suffers.
The predictions of modern physics are phenomenally accurate in many domains. But we haven't run tests in nearly enough domains to claim perfection yet. And we've no need to be defensive about it. Science is the only way to the next truth, and that's good enough for me.
Lets get one thing clear. They have shown no such thing. This is the 3rd non peer reviewed "look at my microwaves" report on this device. The link is to some internet magazine. This will turn out to be just like every other perpetual motion device. Experimental error, and mistakes and just straight out sloppy experimental work like the last 2. We know EM theory and practice very well and right now we have fans of result finding what they want to find.
Also any zero propellent drive is also an over unity device. Easy to prove.
If information wants to be free, why does my internet connection cost so much?
Oh i read them. The NASA ones. And quite frankly they are shit. And rightly didn't get properly published.
You do know that a reactionless drive means not only that momentum is not conserved. But that the laws of physics are different in different places. Also that energy is not conserved. A reactionless drive is always a over unity device. Or are you just batting for your beloved germans. Perhaps if this was done properly i would take them more seriously. But a magazine and a talk (not peer reviewed) don't count.
Also you really don't know your physics all that well.
If information wants to be free, why does my internet connection cost so much?