NASA Peer-reviewed Paper on Controversial EM Drive Published
EmDrive (Credit: Satellite Propulsion Research Ltd.)
A long-awaited, peer-reviewed scientific paper has been published that indicates the controversial EM (Electromagnetic) Drive appears to work even though it apparently violates one of the laws of motion.
In case you’ve missed the hype, the EM Drive, or Electromagnetic Drive, is a propulsion system first proposed by British inventor Roger Shawyer back in 1999.
Instead of using heavy, inefficient rocket fuel, it bounces microwaves back and forth inside a cone-shaped metal cavity to generate thrust.
According to Shawyer’s calculations, the EM Drive could be so efficient that it could power us to Mars in just 70 days.
But, there’s a not-small problem with the system. It defies Newton’s third law, which states that everything must have an equal and opposite reaction….
Yet in test after test it continues to work. Last year, NASA’s Eagleworks Laboratory team got their hands on an EM Drive to try to figure out once and for all what was going on.
The new peer-reviewed paper is titled “Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum“, and has been published online as an open access ‘article in advance’ in the American Institute of Aeronautics and Astronautics (AIAA)’s Journal of Propulsion and Power. It’ll appear in the December print edition.
Read the full story.
55 responses to “NASA Peer-reviewed Paper on Controversial EM Drive Published”
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Hmmm.
That’s good because while basing your propulsion on d/dt(mv) = 0 is fun, and works, not holding m constant comes out against you when solving for dv.
Very interesting, I do remember hearing that eliminating noise and external influences was a particularly difficult challenge in these tests. Would be a really impressive advancement in propulsion if it works….
It would be a bombshell for physics, too.
Good they needed a kick in the pants.
It’s always a good when we stumble across something we can’t reconcile with current understanding
Good for textbook publishers anyway. 😉
I wonder if this seemingly unrelated news item might help explain things:
http://www.spacedaily.com/r…
http://www.eso.org/public/a…
A magnetar’s 10 to the 10th power tesla field has (as per the wiki) an energy density of 4.0×1025 J/m3, with an E/c2 mass density >10to the 4th times that of lead.
“The vacuum itself is polarized, becoming strongly birefringent, like a calcite crystal.”
https://www.extremetech.com…
I hear that the Dirac sea may play some part,
I heard about the research from Larry Smalley and Ning Li
http://taminggravity.com/ar…
Then there were the lifter ion wind folks that fooled themselves
I didn’t think much of all that at first. But then–could an EM drive–with a power level similar to what Large Hadron needed to find the mass-indicing Higgs–coupled with some of the other tech–give us a real spindizzy where each tech on its own is more or less a dead end.
I begin to think there is something to all this–just tying to tace any connections….
Hey–one more reason for SLS.
Just look at the frustrum this would make!
https://forum.nasaspaceflig…
https://www.nasa.gov/sites/…
So that explains the cost. It’s that Nazi bell all over again!
I get a feel that this is a thing kind of like it was with FTL neutrinos at OPERA experiment a few years back. OMG it’s breaking laws of physics and scientists don’t know how or why. New physics gonna be great. Wait, it’s just flaws in equipment or something. Get back to regular physics.
If we didn’t have 5 different researchers getting similar results, I would agree with you. This is simply the first to be published in a peer-reviewed AIAA publication, which makes everyone sit up and take notice. There will be an on-orbit test next year of a different version of EM drive by Guido Fetta’s company. One of the good things about cheaper access to orbit is that these tests can be done with less money.
this is the ideal test to run out of ISS.
Assemble a small Sat, toss it out the airlock. Stabilize it and film it.
That’s certainly the way to bet – but the Em Drive has passed a lot of tests and still looks good. The FTL neutrinos, and the SETI signals that were clearly the work of intelligence (microwave oven), and all the others you could name, didn’t take nearly this long to debunk.
And remember the previous experiments that violated “known” laws of physics? Like Rutherford discovering the atomic nucleus, for example? If the phenomenon is real, we’ll keep seeing it in experiments, and we’ll develop theories about what we see, and test them. If it’s not real, we’ll eventually figure that out too.
It’s a matter of time, either way.
The FTL neutrinos were always suspected of being due to experimental setup error, they knew it was a bad reading, it just took a while to find and re-seat the loose cable. However, the press took the story and ran with it before the scientists working on the project could fix the problem.
And it actually took 17 years to figure out that perytons were caused by prematurely opening the door of a microwave oven.
LOL. Well it was also that the scientists were not shy about “sharing” their excitement about their “discovery”.
Not so. It was more a tentative “this is weird, but we’ve done the neutrino experiment several times over the course of nearly a year and we can’t find what we did wrong” call for validation from other researchers. The press ran with the story.
“OPERA announced its results on September 23rd, 2011 at a special seminar at CERN. The team did not state that it had observed a violation of relativity, and instead of using phrases like “evidence for” or “discovery of,” it called the data an “anomaly.”
http://nautil.us/issue/24/e…
That was after they got egg on their faces about it. But at the time, they didn’t bother to correct because the hype is useful… if you’re right. And if not, you can blame it on the press. Same thing that happened with Cold Fusion, quantum entanglement, etc. Everyone is in such a hurry to get fitted for their Nobel Prize tuxedo…
…. NO.
The initial announcement called the data an anomaly. They immediately set up collaborative experiments to figure out what had happened.
You really ought to read the article, because your statement is completely wrong.
Then you should read it again. Or, do you not remember it at time? There were several months where they went along with they hype and it was only after no one else could replicate the data and they tried to replicate it that they realized their error and had to retract the claim. That article is simply Ereditato’s rationalization. Revisionist hindsight.
From the original 2011 press release:
“[M]any searches have been made for deviations from Einstein’s theory of relativity, so far not finding any such evidence. The strong constraints arising from these observations makes an interpretation of the OPERA measurement in terms of modification of Einstein’s theory unlikely, and give further strong reason to seek new independent measurements.
“This result comes as a complete surprise,” said OPERA spokesperson, Antonio Ereditato of the University of Bern. “After many months of studies and cross checks we have not found any instrumental effect that could explain the result of the measurement. While OPERA researchers will continue their studies, we are also looking forward to independent measurements to fully assess the nature of this observation.”
“When an experiment finds an apparently unbelievable result and can find no artefact of the measurement to account for it, it’s normal procedure to invite broader scrutiny, and this is exactly what the OPERA collaboration is doing, it’s good scientific practice,” said CERN Research Director Sergio Bertolucci.”
https://press.cern/press-re…
That’s not the issue here. It was that they did not correct the press when they reported “OMG! FTL! WTF! LOLZ!” And that is why Ereditato quit. I don’t agree with it because, it shouldn’t matter what the chattering classes say/think but… scientific politics is not scientific.
Ohh, very nice shift of the goalposts.
Well done, very subtle.
He resigned because there was internal backlash at OPERA after the loose cable was found. Which is, by the way, discussed in the first article that I gave you a link for but you did not bother to read.
No, it just appears we have been arguing about different things this whole time. The loose cable was just WHY the erroneous results were obtained. He was “fired” because of the way he (failed to) manage the publicity and made CERN look bad. You say it was the press’s fault. I say it because he was hoping for glory.
He wasn’t fired, he resigned.
Well, based on the original press release, it certainly doesn’t come off the way you are saying.
Read you own link again. And read some of the other writings about that whole fiasco. He “resigned” because the board voted no confidence in him. Ie; he was politely fired.
*SIGH*
“In March of 2012, as the dust settled, the OPERA collaboration held another vote, this time to determine whether the collaborators had confidence in the leaders of the experiment. Each member institution got one vote. The tally ended at 16 to 13 favoring no confidence with several abstentions, well short of the two-thirds majority required to impeach the leadership, but enough to send a strong message. Both the OPERA leader, Ereditato, and the experimental coordinator, Dario Autiero, resigned.”
Resignations are not polite firings.
And of course, you ignore that the decision to make the announcement in the first place was made not by Ereditato and Autiero, but by a vote.
“Large experimental collaborations like OPERA have bylaws for dealing with controversy, and voted to announce the results in public by a large majority of the collaboration. Just a few individuals voted against the announcement.”
Sigh… is right. Seriously go read something else besides the article that was approved by and supports Ereditato. Or don’t, I don’t care. I’m outta here. Happy ‘Merican Turkey Day!
Sure. I’ve gone through about a dozen, and they all say about the same thing, e.g.,
“Some 16 group leaders voted against the pair yesterday, while 13 voted in their favor and several others abstained, the source says. Although collaboration rules specify that a two-thirds vote is needed to remove experiment leaders, the result meant that a majority wanted the pair gone. Ereditato apparently resigned his post a few minutes after the result of the ballot was known, whereas Autiero waited until today [Mar. 30, 2012] to step down. But it’s unclear what their positions will now be within the collaboration.”
http://www.sciencemag.org/n…
“Their resignation was almost certainly inevitable after such a high-profile error. I do have some sympathy for the pair, though, because the results were definitely not presented as being definitive, and OPERA’s results were opened up for the purpose of debate and discussion in the physics community.”
http://www.forbes.com/sites…
careful scientists start a report with “Anomalous signals
detected with XXX” and follow with “While this is consistent with New physics, we wish for collaborative efforts to eliminate sources of noise”…
As far as I understood, further testing will be required to completely rule out other possible sources of thrust.
AKA: Funding!!!!1!
Considering that the current test-article was built on the private kitchen table of one of the authors, a little bit of funding to finally settle the question if this thing actually works or not can’t be too much to ask for, right?
If they demonstrate that it actually isn’t working as intended, all those people around the world who are trying to prove it can put their efforts towards more useful fields. 🙂
They will just assume its a government conspiracy to cover it up and redouble their tin-foil.
I’m wondering if asymmetrical thermal emissions emitted by such a device might explain the feeble net propulsion force created. When microwaves are employed, heat is generated.
In that case a cooking hotplate would also generate a similar thrust. That would be a fun control experiment.
I believe though that the EM drive exceeds the accountable emission force for its surface area.
thin plates move more then thick ones
From conclusions of the paper:
“Although thermal shift was addressed to a degree with this test campaign, future testing efforts should seek to develop testing approaches that are immune to CG shifts from thermal expansion.”
If this device works in microgravity, it will have advantages over lightsails and ion propulsion, but that’s it. Plasma propulsion is the propulsion of choice for humanity to colonize the Solar System.
One of the things mentioned in the paper is that the test equipment was optimized for a quick demonstration of thrust, …not for maximum efficiency in terms of N/Watt, or in N/kilo. Once these are optimized, a number of folks believe that 2-3 orders of magnitude improvements can be made. That, of course will require time and money.
“if this device works in micro-gravity” – you’ve said a mouthful there, Jacob. Also, if it works away from the Earth’s magnetic field, etc.. Next step will be to test at the ISS and, subject to a positive result, much further out in cis-Lunar space. Is this a possible use for Orion? Just strap it on and let’s go get ourselves a piece of assteroid. 🙂 Regards, Paul.
LEO won’t be much different than sea level from an Earth geo-magnetic perspective. You really do have to throw it out to at least GEO before Earth’s magnetic influence diminishes to the point where its effect (or lack there of) on an EM drive would be definitive.
It could be useful even if it only works to LEO altitudes. A lot depends on mass of the required power source just as it does with ion thrusters.
NEXT ion thruster: 34 mN/kW
This EM drive: 1.2 mN/kW
Photon reflector (2P/C): 0.0066 mN/kW
Photon emitter (P/C): 0.0033 mN/kW
Even if thermal emission is occurring the thrust is a lot higher than would be accounted for by photons. Interesting, looking forward to next test. Cubesat?
What’s next is further laboratory testing – to determine if the anomalous thrust levels are real or if they are from experimental error, and if the anomalous thrust is confirmed, then determine if it is from previously unobserved effects. After that, tests on how to optimize its functionality will be done. This is many years away from in-space tests.
In NASA-speak, this is TRL-1
In-space flight tests won’t come before TRL-7
https://www.nasa.gov/sites/…
“This is many years away from in-space tests.”
For NASA.
It is easy to see someone else, public or private, being able to launch a small one of these to see what it will do before NASA can get its paperwork done.
Well, maybe. You don’t take something off a lab bench and then throw it into space. There’s a considerable amount of work that goes into preparing something to actually function in space, which is what the TRL chart shows.
Sure, anyone can launch one of these things into space that will freeze up and die, but then they’ve a. wasted money and b. haven’t shown whether the thing works or not.
Or not. What NASA’s TRL chart actually shows is how to do something that takes the longest time and requires most documentation and “management” possible. /snark
You *can* design a basic experimental apparatus for the space environment without having to baby step through NASA’s generic and arbitrary developmental process.
No, it’s a logical progression of taking a technology from theoretical concept through lab work to development and testing to the point that technology is ready for practical use.
TRL charts like this one are used all over the world.
Monkeys see monkeys do…
O___o
Do you read what you type before you hit “Post”?
Do you?
I’m sorry if I am disrupting your preception of “How things are done”…. lol
Yes, which is why my posts make sense.
but are boring.
I do occasionally stir up controversy in spite of that, lol
You forgot about Numerology.
Think numerology is odd–try spirolaterals
http://mathworld.wolfram.co…
http://www.conanhughes.com/…
They’ll just blare Beiber music in your cell…