An article at NasaSpaceFlight.com is claiming that the superficially reactionless EmDrive has again been tested at NASA Eagleworks, this time in hard vacuum, and the anomalous thrust is still being detected:
A group at NASA's Johnson Space Center has successfully tested an electromagnetic (EM) propulsion drive in a vacuum – a major breakthrough for a multi-year international effort comprising several competing research teams. Thrust measurements of the EM Drive defy classical physics' expectations that such a closed (microwave) cavity should be unusable for space propulsion because of the law of conservation of momentum.
With the popular explanations of thermal convection or atmospheric ionization being ruled out by operation in vacuum, and thrust thousands of times greater than expected from a photon rocket, is it time to start taking the EM Drive seriously as a fundamentally new form of propulsion, and possibly a door to new physics?
Roger Shawyer, the inventor of the EmDrive, claims that the device's efficiency will scale even further with greater levels of power, potentially enabling fast interstellar travel powered by a radioisotope thermoelectric generator or nuclear fission.
Previously: NASA Validates "Impossible" Space Drive's Thrust
Related Stories
This story from a Wired article: NASA is a major player in space science, so when a team from the agency this week presents evidence that "impossible" microwave thrusters seem to work, something strange is definitely going on. Either the results are completely wrong, or Nasa has confirmed a major breakthrough in space propulsion.
British scientist Roger Shawyer has been trying to interest people in his EmDrive for some years through his company SPR Ltd. Shawyer claims the EmDrive converts electric power into thrust, without the need for any propellant by bouncing microwaves around in a closed container. He has built a number of demonstration systems, but critics reject his relativity-based theory and insist that, according to the law of conservation of momentum, it cannot work.
NASA states... "Test results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma"
After months of speculation and leaked documents, NASA's long-awaited EM Drive paper has finally been peer-reviewed and published [open, DOI: 10.2514/1.B36120] [DX]. And it shows that the 'impossible' propulsion system really does appear to work. The NASA Eagleworks Laboratory team even put forward a hypothesis for how the EM Drive could produce thrust – something that seems impossible according to our current understanding of the laws of physics.
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.
takyon: Some have previously dismissed EmDrive as a photon rocket. This is addressed in the paper along with other possible sources of error:
The eighth [error:] photon rocket force, RF leakage from test article generating a net force due to photon emission. The performance of a photon rocket is several orders of magnitude lower than the observed thrust. Further, as noted in the above discussion on RF interaction, all leaking fields are managed closely to result in a high quality RF resonance system. This is not a viable source of the observed thrust.
[...] The 1.2 mN/kW performance parameter is over two orders of magnitude higher than other forms of "zero-propellant" propulsion, such as light sails, laser propulsion, and photon rockets having thrust-to-power levels in the 3.33–6.67 μN/kW (or 0.0033–0.0067 mN/kW) range.
Previously: NASA Validates "Impossible" Space Drive's Thrust
"Reactionless" Thruster Tested Again, This Time in a Vacuum
Explanation may be on the way for the "Impossible" EmDrive
Finnish Physicist Says EmDrive Device Does Have an Exhaust
EmDrive Peer-Reviewed Paper Coming in December; Theseus Planning a Cannae Thruster Cubesat
(Score: 4, Insightful) by ikanreed on Friday May 01 2015, @06:07PM
I'm more inclined to trust this blog post than the last blog post, but I'll be waiting on the peer reviewed paper too.
The whole mysterious universe site's background levels of bullshit put this story on my bullshit radar, and it's not going away for a while. This new website is an amateur community, which is more reasonable than "batshit conspiracy site", but not up to the level of actually credible.
Anyone got a genuinely reliable source yet? Big science news like this seems like it would have some sort of official channels to put out.
(Score: 5, Informative) by SubiculumHammer on Friday May 01 2015, @06:21PM
I mean, this white paper posted in 2014 on the official NASA site at least suggests that NASA doesn't automatically reject all this as quack science.
http://ntrs.nasa.gov/search.jsp?R=20140006052 [nasa.gov]
(Score: 2, Informative) by khallow on Friday May 01 2015, @07:13PM
(Score: 5, Insightful) by wantkitteh on Friday May 01 2015, @08:26PM
I don't think it's a question of finding a genuinely reliable source - there's been a few of those already that have said this thing works. What we appear to have is a genuinely extraordinary claim that's holding up against the expectation of genuinely extraordinary proof. So far. And let's hope it goes all the way!
(Score: 3, Funny) by Jeremiah Cornelius on Friday May 01 2015, @07:03PM
I just ABHOR a vacuum.
They make me want to expel my propellant...
You're betting on the pantomime horse...
(Score: 2) by Hartree on Friday May 01 2015, @08:10PM
"They make me want to expel my propellant..."
Just don't do it too quick, or it'll really interfere with your social life.
(Score: 2) by BK on Saturday May 02 2015, @02:06AM
Indeed. Vacuums suck!
...but you HAVE heard of me.
(Score: 4, Interesting) by jmorris on Friday May 01 2015, @07:15PM
So three labs show thrust where there can be none by every law of physics we know. Ok. Only one way to really know for sure, build one big enough to keep the ISS boosted, install it and let it run for a year, if the orbit is still good it will be time to rewrite the physics books.
It is about time we actually got a drive system more advanced than throwing mass out the rear end of the vehicle, now maybe we will get a few people off of this rock before we all die of insanity.
(Score: 5, Insightful) by GreatAuntAnesthesia on Friday May 01 2015, @07:41PM
That would be weird...
" so we've got this new propulsion system. We've built it, tested it, scaled it up, tested it again, and now it's flying an expedition to mars."
" cool, how does it work?"
"nobody knows..."
(Score: 5, Insightful) by maxwell demon on Friday May 01 2015, @08:14PM
Not that weird. Has happened all the time.
"You put the meat on the fire, and then it gets much easier to eat."
"How does it work?"
"Nobody knows."
"We put that substance from a calf's stomach into the milk, then it gets hard and remains edible for a long time."
"How does it work?"
"Nobody knows."
"We put that stuff into a cask and let it stay there a while, and then it tastes different and doesn't get bad as quickly, but if you drink too much of it, you'll lose your mind."
"How does it work?"
"Nobody knows."
"If we infect people with the harmless cowpox, they won't get the dangerous smallpox."
"How does it work?"
"Nobody knows."
"This substance produced by that mold kills bacteria, we use it to heal people."
"How does it work?"
"Nobody knows."
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Insightful) by Grishnakh on Saturday May 02 2015, @12:09AM
Here's another one, which still applies today:
"You jump into the air, and then you fall back to the ground. Or, you drop something from a height above the ground, and it falls to the ground. We call it 'gravity'."
"How does it work?"
"Nobody knows."
(Score: 2) by frojack on Saturday May 02 2015, @03:00AM
Maybe this is propelling "Daaarrrrrk Maaaatter".
"But what is this Dark Matter of which you speak?"
"Nobody Knows".
Seriously, given everything else that has been pinned on dark matter, I'm surprised some hasn't made such claims already.
The only question remaining, is were these experiments detected by the aliens? Will the now be forced to come and wipe us out before this gets out of hand?
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Saturday May 02 2015, @05:02AM
Someone has. When this was going around last time I thought of that, and with a little searching found someone else who had thought of it earlier.
This vacuum test makes it a little more likely, but it's still a very long shot.
(Score: 2) by PiMuNu on Saturday May 02 2015, @05:52AM
The difference is, we now know how lots of stuff works and this is different to all of that. So it's like putting wood on the caveman's fire and the fire goes out - it is in contravention to everything he knows.
Except now, all you have is someone "telling" you that it is wood... then you have to be very careful and make sure you check very thoroughly both the claim that it is wood, and the claim that the fire goes out.
Especially when people come up with this sort of crap every other day and try to sell it for $$$.
(Score: 2) by maxwell demon on Saturday May 02 2015, @06:24AM
Except that the post I replied to was already in the hypothetical situation that we are using it for going to Mars. Which certainly implies that in that hypothetical scenario the drive works, because if it didn't work, it certainly would be noticeable when trying to use it to get to Mars.
I agree that at the present point in time it is reasonable to be sceptical. There's a good chance that it is indeed snake oil. However should the drive ever be regularly used in space ships, it will be a safe assumption that it works, or else someone would have noticed by then.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Rivenaleem on Tuesday May 05 2015, @08:59AM
"Magnets!"
"How does it work?"
"Nobody Knows."
(Score: 2) by Hartree on Friday May 01 2015, @08:15PM
" so we've got this new navigation system. We've built it, tested it, tested it again, and now it's helping sail an expedition beyond the end of the Mediterranean past Gibraltar."
" cool, how does it work?"
"nobody knows... We call it a lodestone, though."
(Score: 3, Funny) by Ethanol-fueled on Friday May 01 2015, @08:20PM
This fucking thing had better sound cool.
I'm not flying with it if it makes a stupid noise, like how things sound in Star Wars Episode I. What good is a menacing star-destroyer with ion cannons and tail fins on the ass-end if it sounds like, "Boo-boo-boo-boo-boo-hee-hee-hee-heee!"
(Score: 2) by Mr Big in the Pants on Friday May 01 2015, @10:57PM
Are you fucking serious?!
I get a chance to fly in this thing I will take it even if it sounds like a fairy shitting itself politely...
(Score: 2) by BK on Saturday May 02 2015, @02:09AM
But what if it sounds like Jar Jar...?
...but you HAVE heard of me.
(Score: 2) by Mr Big in the Pants on Saturday May 02 2015, @06:34AM
I believe that would defy the moral laws of physics.
(Score: 0) by Anonymous Coward on Saturday May 02 2015, @11:04AM
"Powering up the Jar-Jar drive"
mmmmmmMMMMMMMMMEEEEESA-MEESA-MEESA-MEESA-MEESA-MEESA
(Score: 3, Interesting) by SubiculumHammer on Friday May 01 2015, @07:52PM
How depressing would it be if the stars would always be out of reach. The article states that such a drive might reach alpha centauri in less than a century, and that is probably absent any innovations that would occur after we find explanations for how it works...if it works, I mean.
(Score: 2, Insightful) by khallow on Friday May 01 2015, @09:27PM
(Score: 2) by mr_mischief on Friday May 01 2015, @10:09PM
I'm just hoping to extend my life until the singularity. Then the computer will help me figure out how to get the rest of the way to another world. Thanks, Ray!
(Score: 0) by Anonymous Coward on Friday May 01 2015, @08:01PM
> Only one way to really know for sure, build one big enough to keep the ISS boosted, install it and let it run for a year
What makes you think that is even a remotely reasonable way to "know for sure?" We should build a full-scale system and deploy it in one of the most conspicuous and expensive possible applications and just cross our fingers it won't fail in a spectacular way?
How about all the people who aren't crazy pants take it one step at a time in the lab for a while and let the first deployed system be an unmanned satellite that only does a couple of weeks of testing?
(Score: 3, Interesting) by jmorris on Friday May 01 2015, @08:11PM
If you expect people to accept a drive that operates on unknown principles it needs to be demonstrated in a splashy way. Apparently it just sits on a bench and quietly draws electricity and generates a very small thrust so it shouldn't be dangerous.
Flying it on the ISS sounds a lot simpler than building an entire space vehicle to find out if it generates thrust in low orbit. Regular missions bring cargo to it, it has plenty of electrical generation capacity, and so on. And if it works it is an instant improvement to the station.
(Score: 1) by Bogsnoticus on Saturday May 02 2015, @02:38PM
"If you expect people to accept a drive that operates on unknown principles it needs to be demonstrated in a splashy way."
Given how 95% of the population accept mobile phones, computers, the internal combustion engine, electricity generation, televisions, and all sorts of modern appliances with absolutely no understanding on how they work, why should one more device whose operation is beyond their ken be hard for them to accept?
Most will be happy if;
- It works
- Doesn't kill them immediately, or further down the track.
- Doesn't shrink their testicles.
- Doesn't produce the "brown note" and make them crap themselves when it is switched on.
The curious 5% can entertain ourselves by producing theories, conspiracies and just generally pondering the math behind it until a suitable answer is discovered.
Genius by birth. Evil by choice.
(Score: 3, Touché) by soylentsandor on Friday May 01 2015, @08:41PM
That would be the sensible and responsible thing to do.
But come on, where's the fun in that?
(Score: 2) by frojack on Saturday May 02 2015, @03:26AM
Besides, if you want a visit from the Vulkans, we'v got to strap this thing to a ship named Phoenix, and go for it. 2063 is just around the corner guys.
No, you are mistaken. I've always had this sig.
(Score: 3, Insightful) by gnuman on Friday May 01 2015, @09:11PM
What makes you think that is even a remotely reasonable way to "know for sure?"
ISS was built for these sort of things.
1. It has lots of power, check
2. It is built for experiments, check
3. It is maned, and so people can adjust it and do various experiments on it while in orbit, check.
Clearly, first they will test it on Earth to try to figure out how it works. But this drive needs to be tested in space too.
Anyway, these are very very very exciting news. When no one can readily explain *why* this works or *how*, that means there could be exciting physics here.
(Score: 0) by Anonymous Coward on Saturday May 02 2015, @12:58AM
let the first deployed system be an unmanned satellite that only does a couple of weeks of testing?
But this drive needs to be tested in space too.
Thank you for demonstrating which side of the argument is based on paying attention.
(Score: 2) by takyon on Saturday May 02 2015, @01:27AM
Honestly, you don't need to test it in space at all. VASIMR and other ion engines were tested right here on Earth. If this thing can create 4 times or the promised hundreds of times more thrust per Watt than ion engines, it will be obvious. The vacuum testing eliminates some of the skepticism.
NASA needs to do two things: refine it to work very predictably, and investigate claims of >1 Newton of thrust per kilowatt (or the insane 300 Newtons per kilowatt). State of the art ion engines produce 0.04 Newton of thrust per kilowatt.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by LaminatorX on Saturday May 02 2015, @04:45AM
I think that it needs to be tested not only in a vacuum, which I'm delighted they've done, but outside the Earth's magnetosphere. I'm excited by this, but I'm not convinced that it's not following conservation principles by infinitesimally pushing-against/degrading the planet's magnetic field.
(Score: 2) by Immerman on Saturday May 02 2015, @01:49AM
The only problem with that is that the ISS is a very large system, requiring a comparatively large amount of thrust, and only for station keeping. It's basically a good idea though: if they can build a satellite consisting of basically just the thruster, solar panels, and a communications/control/monitoring system, then the same amount of thrust will generate radically more obvious results - and also allow for radically more precise measurements of the effect.
I would think a good experiment would be to have a smallish solar-powered EM-drive placed in an orbit outside the heavily populated LEO "shell" (to avoid potential collisions), and have it attempt to spiral outwards.
If successful it would:
1) Prove that the thing works beyond any shadow of a doubt. We're not talking about the general public here - even a small satellite impossibly gaining altitude would be as attention-grabbing as an air-raid siren to every physicist and engineer on the planet.
2) Allow us to possibly detect if the thrust varies with (or without) a predictable pattern. At present we know essentially nothing about this phenomena - if there are any variations in its thrust they could provide clues to the underlying physics. As it climbed we'd get variations in solar wind, magnetic field, spacetime distortion... lots of relationships that might be exposed.
3) provide ever-more precise data as it climbs out of the chaotic drag of the nebulous outer atmosphere, without requiring a more expensive launch to higher orbit for an untested system.
(Score: 2) by frojack on Saturday May 02 2015, @03:07AM
Long duration thrust is just as good as a large amount of thrust.
Our problem is doing either efficiently.
If all we have to do is hoist some more solar panels and one or two of these engines, it would be a cheap one time fix.
Just in time to hand it all over the Russians.
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Saturday May 02 2015, @11:16PM
> law of physics
It's funny to see how a completely meaningless concept like the universe following a law *that has been formalized inside of it* is taken seriously. It's like science has forgotten science itself and has become a habit.
We can discover free energy or faster than light travel, if those are features of the universe. Laws are not in the way except in your brain.
(Score: 2, Interesting) by Anonymous Coward on Friday May 01 2015, @07:56PM
I saw this over on digg first and surfed around some links until the tablets battery gave up.
what i gleened from this is that NASA has confirmed that something fishy is going on -aka- somethings doesn't add up with the laws of the physics as we postulate them.
It could be a new effect -or- a very complicated interpretation of "oldskool" physics.
I got the impression that some interpret the results so that electro-magnetism isn't layered ontop of gravity (gravity-space bends and the magnetic and electrical fields get bent too) but rather that magnetic and electrical fields are part of space-time .. interwoven. thus by "manipulating electric and magnetic fields correctly" we can also bend / form /shape space time.
If this is the correct interpretion then we have to rename space-time to electro-magnetic-space-time ? electro-gravity? magneto-space? Also there would be no violation of impulse conservation. The "electron" would become something akind to "raster-points" of space-time : ) maxwell version 2.0?
Also i saw a tablet where the "efficiency", that is the amount of electrical power to "amount of effect" was listed for different experiments and it was ... going up really fast. like 0.1 efficient to 800 efficient. 1kw input could lift 1 ton? soon?
Furthermore soembody was saying that on earth it can only counter gravity ... lift a car for example but not provide horizontal acceleration or its efficient would drop ... something.
Another smart post said that if the "efficiency" reaches a certain amount that the devices could be mounted on a wheel and then turn the wheel driving a electrical generator at the center that in turn would power the devices .. thus creating a "perpetuum mobile".
Me personally I would greatly welcome a "shake up" of what the human-intellectual-sphere considers possible and also because it would vindicate my (childish? eh? eh?) fascination with
MAGNETS!!! AWESOME!!
Then again some multi-beelleon dollar science project would really have to worry about turning into donkeys, with pointy hats and standing the corner?
(Score: 3, Insightful) by tangomargarine on Friday May 01 2015, @08:53PM
Another smart post said that if the "efficiency" reaches a certain amount that the devices could be mounted on a wheel and then turn the wheel driving a electrical generator at the center that in turn would power the devices .. thus creating a "perpetuum mobile".
Yeah, that's called Perpetual Motion [wikipedia.org] and when you bring it up most self-respecting scientists laugh you out of the room.
It's a simple concept; the problem is that as far as we know it's impossible.
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 2, Disagree) by snick on Friday May 01 2015, @09:14PM
All true. But we are talking about a drive with properties which most self-respecting scientists laugh out of the room.
As long as you are getting laughed out of the room, why not go big? Perpetual motion ... time travel ... match all the socks in your laundry basket. (yeah, I know, that last one is't plausible)
(Score: 2, Insightful) by khallow on Friday May 01 2015, @09:31PM
(Score: 0) by Anonymous Coward on Friday May 01 2015, @10:19PM
That phenomenon could be manifesting itself as dark energy.
(Score: 3, Funny) by tangomargarine on Friday May 01 2015, @10:30PM
"And of course there's the time Rodney blew up a solar system."
"Quit exaggerating! It was only four-fifths of the system. And it was an accident."
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 0) by Anonymous Coward on Friday May 01 2015, @09:53PM
Yeah, that's called Perpetual Motion and when you bring it up most self-respecting scientists laugh you out of the room.
Obligatory Simpsons [youtube.com]
(Score: 2) by HiThere on Saturday May 02 2015, @01:54AM
The thing is that there are certain kinds of "perpetual motion" that happen. What you can't (usually) do is extract energy.
OTOH, there is a design for a nano-machine that should work as a perpetual motion where you can extract energy (though not much). Basically it's just a ratchet that's small enough that occasionally it will vibrate in a way that winds the ratchet. (But you can't have significant back pressure or it stops working, so you need to use the twist as you generate it.)
There are lots of "edge cases" that don't fit into the way we normally think about physics. Every once in awhile one of them becomes important enough to require a detailed explanation, and then you get something like quantum theory. (That said, the nano-machine I described doesn't break any actual law of physics, just the way we normally talk about it. When you get small enough thermodynamics stops working because you aren't dealing with a large enough collection of "pieces" to make treating it statistically a valid approach. But quantum uncertain continues to work.)
And *that* said, we know that the standard model of physics is incomplete. We just don't have a good idea of how to modify or extend it. Perhaps this will give us some clues. (And quite likely, if it proves out it will have limits that will restrict it's usefulness.)
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 3, Informative) by tangomargarine on Sunday May 03 2015, @05:32PM
Yes, it's called a Brownian ratchet [wikipedia.org] and, although it took them a long time to do so, scientists finally figured out why it wouldn't work.
The PM Wiki article is quite in-depth. It's a good read.
The other "gotcha" they mention is that things that *appear* to be perpetual motion machines (e.g. something that gets its input from tidal energy or radioactive decay) may work for an extremely long amount of time, but they will eventually fail because of entropy (plutonium will eventually be totally decayed in millions of years).
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 3, Interesting) by ancientt on Saturday May 02 2015, @02:10AM
Solar cells provide perpetual motion machines by old definitions. The idea of turning light into motion would have been shocking a few thousand years ago, but nobody is shocked today because the idea of turning radiation into motion is considered basic science and the definitions we use for perpetual motion are updated to reflect that. The idea that there could be something new we didn't understand a few years ago and understand tomorrow is basic science. When a scientist encounters something that doesn't do what is expected, a scientist tests to see if any of the possible understood explanations can be used to understand the new thing first. That's what phase we're in now.
From TFA:
That's ruling out, piece by piece, the understood explanations.
One of two things is happening here. Either we are encountering something new, or we're encountering something known in a new context. One is a breakthrough in physics, the other a breakthrough in engineering. Either is exciting and useful.
Consider a simplified version, that's probably more of an analogy than example: You turn on a flashlight and measure the propelling force of the light and it is greater than your theory predicted. Likely the explanation is that the extra force measured is demonstrating a failure of your theory's comprehensiveness, but the possibility exists that your flashlight is producing additional thrust due to something that any current knowledge would fail to include.
This is exciting news! The worst case scenario is that very smart people are going to learn to include an idea they hadn't previously considered. That means that engineers will be able to improve ideas and technology immediately. The better case is that there could be something new to learn and that means there are potentials to create whole new theories about how things work. Either scenario is great for science.
We use dams, solar cells, wind and geothermal energy right now and all of those are perpetual motion for the common man. Science can explain where the energy is coming from, but there is no limit any human can personally observe to how much energy can be eventually used. Even if this is a tiny breakthrough along the lines of "of course it turned out to be explained by theory X that everyone knows," it will be something that has new applications to existing systems. Of course we all hope it will turn out to be "this new thing we didn't know before" so that we can better understand our universe and so far... so good.
This post brought to you by Database Barbie
(Score: 2) by tangomargarine on Sunday May 03 2015, @05:35PM
Technically solar power isn't perpetual because in billions of years (or whatever) the sun itself will burn out.
And isn't one problem with solar-powered space probes that they eventually get too holed up by bits of dust even in the "vacuum" of space.
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 0, Offtopic) by SubiculumHammer on Friday May 01 2015, @07:56PM
I want I need I want I neeed I want I neeed I want I need
~~~~~~~~~I want I need I want I need ~~~~~~~~~~~
I crave I need I crave I neeed I crave I neeed I crave I need
~~~~~~~~~I want I need I want I need ~~~~~~~~~~~
For this to be True
(Score: -1, Troll) by Anonymous Coward on Friday May 01 2015, @08:15PM
how old were you when the fuse in your brain blew and didn't allow conduction of new ideas?
from a philosophical stand-point the declaration of a immutable law of conservation of momentum would lead to one outcome: instant suicide -aka- this prison sucks!
(Score: 0) by Anonymous Coward on Friday May 01 2015, @09:54PM
how old were you when the fuse in your brain blew and didn't allow conduction of new ideas?
That depends. What time is it?
(Score: 1, Insightful) by Anonymous Coward on Friday May 01 2015, @09:00PM
Obviously he wants to be a starfarer.
(Score: 1, Funny) by Anonymous Coward on Friday May 01 2015, @09:30PM
Great - now the Vulcans will land in Cleveland
(Score: 2) by isostatic on Saturday May 02 2015, @12:01AM
It was Pennsylvania according to enterprise
(Score: 0) by Anonymous Coward on Tuesday May 05 2015, @06:01PM
Score -1: Pedantic.
(Score: 3, Insightful) by Anonymous Coward on Friday May 01 2015, @09:32PM
Have they accounted for potential interaction with Earth's magnetic field? Redo the test 6 times, with the "engine" pointed north, south, east, west, up, and down, and compare all results.
(Score: 0) by Anonymous Coward on Friday May 01 2015, @10:34PM
How do you know they haven't? Curious.
(Score: 3, Informative) by Fluffeh on Saturday May 02 2015, @05:20AM
From testing, it appears that they may have thought of this:
EmDrive Tests
The following independent tests have been performed for the EmDrive.
A test at 2500 W of power during which a thrust of 750 millinewtons was measured by a Chinese team at the Chinese Northwestern Polytechnical University.
A test at 50 W of power during which a thrust of 50 micronewtons was measured by Eagleworks at the Johnson Space Center at ~760 Torr of pressure. (Summer 2014)
A test at 50 W of power during which a thrust of 50 micronewtons was measured by Eagleworks at the Johnson Space Center at ~5.0×10−6 torr or pressure. (Early 2015)
A test at 50 W of power during which an interferometer (a modified Michelson device) was used to measure the stretching and compressing of spacetime within the device, which produced initial results that were consistent with an Alcubierre drive fluctuation.
All these tests were conducted with a control device that did not produce thrust.
UPDATED
NOTE: a better source was found for the Chinese results, and I have changed this section to reflect that.
Test #1 was conducted at the direction of lead researcher Juan Yang. She tested the device at several power levels and frequencies using the same equipment used to test Ion Drives. The given result above was the largest result produced. Her team estimated that the total measurement error was less than 12%. Source 1 | Source 2
Tests number 2 and 3 were performed multiple times, changing direction of the device and observing a corresponding change in the direction of force. They were not especially careful about controlling for ALL variables however, mostly owing to the lack of funding for the project. The positive tests have resulted in more funding becoming available, although it is still very, very little, and possibly not enough to explain where the error occurred if the measurement is error of some kind.
Test #4 was performed, essentially, on a whim by the research team as they were bouncing ideas off each other, and was entirely unexpected. They are extremely hesitant to draw any conclusions based on test #4, although they certainly found it interesting.
The Eagleworks team has been able to dedicate very little hardware towards this experiment, as there has been almost no dedicated funding for this experiment. The lack of funding is related to how outlandish the claims are to those who understand physics very well, and the lack of adequate explanation on the math behind the devices from the inventors.
(Score: 2) by Fluffeh on Saturday May 02 2015, @05:20AM
Forgot to add the link to the source: https://www.reddit.com/r/Futurology/comments/34cq1b/the_facts_as_we_currently_know_them_about_the/ [reddit.com]
(Score: 2) by choose another one on Saturday May 02 2015, @02:51PM
Wish I could find the original source for that and verify that it's from the experiments and not just something that has got added by the internet.
If true, then I guess it neatly provides a theoretical way for this to work without propellant, and um, wow. Alcubierre has always been interesting mathematically but impossible practically due to requiring things like negative mass. If it turns out all we've got to do is bounce some microwaves around in a tin can to get a warp field then, f**k. Off to sell all my shares in dilithium crystal prospectors...
(Score: 0) by Anonymous Coward on Saturday May 02 2015, @01:02AM
reddit thread
https://www.reddit.com/r/Futurology/comments/34cq1b/the_facts_as_we_currently_know_them_about_the/ [reddit.com]
(Score: 3, Informative) by Anonymous Coward on Saturday May 02 2015, @01:07AM
a few more links
http://en.wikipedia.org/wiki/EmDrive [wikipedia.org]
http://arc.aiaa.org/doi/abs/10.2514/6.2014-4029 [aiaa.org]
http://aviationweek.com/awin/propellentless-space-propulsion-research-continues [aviationweek.com]
http://www.emdrive.com/NWPU2010translation.pdf [emdrive.com]
http://emdrive.com/principle.html [emdrive.com]
http://www.emdrive.com/yang-juan-paper-2012.pdf [emdrive.com]
http://en.cnki.com.cn/Article_en/CJFDTOTAL-YHXB200805027.htm [cnki.com.cn]
http://arc.aiaa.org/doi/abs/10.2514/6.2014-3853 [aiaa.org]
http://ntrs.nasa.gov/search.jsp?R=20110023492 [nasa.gov]
http://nextbigfuture.com/2015/02/more-emdrive-experiment-information.html [nextbigfuture.com]
http://www.freepatentsonline.com/WO2007089284.pdf [freepatentsonline.com]
http://www.pbs.org/wgbh/nova/next/space/improbable-thruster-seems-work-violating-known-laws-physics/ [pbs.org]
http://web.archive.org/web/20121102082714/http://www.cannae.com/proof-of-concept/experimental-results [archive.org]
http://arxiv.org/pdf/0807.1310v5.pdf [arxiv.org]
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140000851.pdf [nasa.gov]
http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/ [nasaspaceflight.com]
https://www.reddit.com/r/Futurology/comments/34cq1b/the_facts_as_we_currently_know_them_about_the/ [reddit.com]