Posted on 11/07/2016 1:06:47 AM PST by LibWhacker
The results of NASA's tests on the 'impossible' EM Drive have been leaked, and they reveal that the controversial propulsion system really does work, and is capable of generating impressive thrust in a vacuum, even after error measurements have been accounted for.
The EM Drive has made headlines over the past year, because it offers the incredible possibility of a fuel-free propulsion system that could potentially get us to Mars in just 70 days. But there's one major problem: according to the current laws of physics, it shouldn't work.
The issue is the fact that the EM Drive defies Newton's third law, which states that everything must have an equal and opposite reaction. So, according to Newton and our current understanding of the world around us, for a system to produce propulsion, it has to push something out the other way (in space, that's usually combusted rocket fuel).
But the EM Drive works without any fuel or propellants at all. It works by simply bouncing microwave photons back and forth inside a cone-shaped closed metal cavity. That motion causes the 'pointy end' of the EM Drive to generate thrust, and propel the drive in the opposite direction.
Despite years of testing and debate, the drive remains controversial. The bottom line is that, on paper, it shouldn't work, according to the laws of physics. And yet, in test after test, the EM Drive just keeps on working.
Last year, NASA's Eagleworks Laboratory got involved to try to independently verify or debunk the EM Drive once and for all. And a new paper on its tests in late 2015 has just been leaked, showing that not only does the EM Drive work - it also generates some pretty impressive thrust.
To be clear, despite rumours that a NASA paper on these tests has passed the peer-review process, the version that's been leaked hasn't been published in an academic journal. So, for now, this is just one group of researchers reporting on their results, without any external verification.
But the paper concludes that, after error measurements have been accounted for, the EM Drive generates force of 1.2 millinewtons per kilowatt in a vacuum.
That's not an insignificant amount - to put it into perspective, the super-powerful Hall thruster generates force of 60 millinewtons per kilowatt, an order of magnitude more than the EM Drive.
But the Hall thruster uses fuel and requires a spacecraft to carry heavy propellants, and that extra weight could offset the higher thrust, the NASA Eagleworks team conclude in the paper.
Light sails on the other hand, which are currently the most popular form of zero-propellant propulsion, use beams of sunlight to propel them forward rather than fuel. And they only generate force up to 6.67 micronewtons per kilowatt - two orders of magnitude less than NASA's EM Drive, says the paper.
The NASA Eagleworks team measured the EM Drive's force using a low thrust pendulum at the Johnson Space Centre, and the tests were performed at 40, 60, and 80 watts.
They were looking for any sign that the thrust could be a result of another anomaly in the system, but for now, that doesn't appear to be the case.
"The test campaign included a null thrust test effort to identify any mundane sources of impulsive thrust, however none were identified," the team, led by Harold White, concluded in the paper.
"Thrust data from forward, reverse, and null suggests that the system is consistently performing with a thrust to power ratio of 1.2 ± 0.1 millinewtons per kilowatt."
But the team does acknowledge that more research is needed to eliminate the possibility that thermal expansion could be somehow skewing the results.
They also make it clear that this testing wasn't designed to optimise the thrust of the EM Drive, but simply to test whether it worked, so further tweaking could make the propulsion system more efficient and powerful.
So where does this leave us with the EM Drive? Again, the results haven't been published as yet - although rumours are circulating that we're getting tantalisingly close to that happening - so we need to take these leaked results with a grain of salt.
But they do offer further evidence that the thrust produced by the EM Drive is real. So it might be time to start trying to figure out how the system could work - and, more importantly, start testing the drive in space.
Thankfully that's scheduled to happen in the coming months, with the first EM Drive already having been launched into space back in September.
And back in June, a team of researchers from Finland proposed a way that the EM Drive could work without defying Newton's third law, by propelling photons as a type of exhaust - although that hypothesis has yet to be tested.
We're still a long way off understanding how the system works - or if it works at all - but a lot of brilliant minds are now seriously considering the possibility that we might have a way to get to space without rocket fuel. We're excited to see what happens next.
I don’t think the vaccum would affect the drive working. It was used in the experiment to show it would work in a vacuum.
Microwave in a vacuum would not be attenuated and scattered like it would be in our atmosphere. That might be the point of the experiment. But microwave is not like laser energy where it is focused. Microwave can be beamed, but it does disperse over distance. Strange.
I’m still not certain about the legitimacy of the actual .pdf that was linked.
This could be pop science BS article. I’m not sure about it.
The source of the article makes me suspect it is BS.
“Leaked NASA paper shows the ‘impossible’ EM Drive really does work”
“Did we just achieve fuel-less propulsion?”
—
The “Leaked” reference tells me it is nonsense.
The reference to “fuel-less propulsion” is certainly totally wrong. It requires an external source of RF power for the drive to work. It is not free power.
It’s not free energy or perpetual motion. It uses electricity to produce the microwaves. Kilowatts....
actually it really does exist.....
Interesting! Bookmarked
I don't think you understood the article. There is absolutely energy expended.
However, there is no reaction mass involved, or more accurately, you don't have to carry it with you. Other rockets make thrust by expelling "stuff" at velocity out their exhaust. Bad news: you have to carry the "stuff" with you until you're ready to expel it, and it's heavy. This "rocket" may be making its own "stuff" (photons) as it goes, so the "lifting heavy stuff for thrust" problem goes away. That's the big win.
My first thought as well upon reading the article. They are just not looking for or measuring the right thing(s).
All EM waves are composed of photons, but the energy of the photon varies inversely proportional to wavelength (E = hc/λ).
If it’s on a NASA email or computer file anywhere, then the Chinese probably already know all about it . . .
I’m still waiting for that Rossi character to produce the LENR E-CAT gizmo that certain people were shilling for here a few years ago.
From what I’ve read of this drive, it sounds like a fairly simple device that could be made cheaply and put in a small enclosure. I say that NASA build one, send it up to the ISS, and have an astronaut fire it up. It really wouldn’t even need a guidance system. Just point it anywhere and turn it on. If it blasts away like a bat out of hell, then we have a working system. If it just sits there and consumes electricity, then it doesn’t work.
I've seen drawings of the device. It has no port for anything to escape from, unless the microwaves are somehow penetrating the metal base. If they can do that, then you'd need a heck of a lot more shielding for the microwave in your kitchen than the mesh it has on front that allows you to view what is cooking.
Supposedly particle/antiparticle pair production occurs all the time—they form then annihilate in short order—resulting in no net change in the energy content of a given volume of space.
One variant on the reasoning of how Shawyer’s device could work, invokes accelerating these particles during their brief existence, resulting in a minuscule reaction force. The cone shape skews the force balance of accelerating fields acting on particle or antiparticle, creating a slight imbalance of the forces. This out-of-balance condition is designated as thrust.
Do light waves have magnetic components like radio waves?
Or is that because the energy level of the particles are lower or because of the wavelength is more narrow in spectrum?
IIRC, incandescent light bulbs generate photons over a wide range of frequencies, but LED are more narrow.
This is a similar issue to the difference between fluorescent bulbs and incandescent bulbs.
ANY EM radiation can be expressed either as waves with a specific wavelength or photons with a specific energy.
Define "crappy".
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