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New NASA research confirms validity of M-Drive (formerly dismissed as pseudoscience) that seems to contradict Newton’s Third Law of Motion. This is a method of producing propulsion using microwaves in a sealed cavity with no expulsion of matter. This could make rocket propulsion, with its inherent massive wastefulness, obsolete. Findings were published in a peer-reviewed journal, Journal of Propulsion and Power, as reported in Aerospace Research Central. Link: http://arc.aiaa.org/doi/10.2514/1.B36120
quote: Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum
Thrust data from forward, reverse, and null suggested that the system was consistently performing at 1.2±0.1 mN/kW . . . . 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)
An attempt was made to suggest a way that the discovery might still be compatible with Newton’s Third Law of Motion:
quote: If the vacuum is indeed mutable and degradable as was explored, then it might be possible to do/extract work on/from the vacuum, and thereby be possible to push off of the quantum vacuum and preserve the laws of conservation of energy and conservation of momentum. It is proposed that the tapered RF test article pushes off of quantum vacuum fluctuations, and the thruster generates a volumetric body force and moves in one direction while a wake is established in the quantum vacuum that moves in the other direction.
Newton did not know about quantum physics, that vacuum is not empty.
What this means is that scientists have discovered Star Trek's "impulse drive."
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I read that there is an upcoming test of the system in space. The thing is, it is not all that expensive. You don't have to worry about expending valuable propellant. Someone estimated that it may take only 70 days for an EM-propelled craft to reach Mars. This is just what it would take to make space travel truly practical. Link: http://www.sciencealert.com/the-impossible-em-drive-is-about-to-be-tested-in-spacePosts: 3742 | Registered: Dec 2001
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CPG Grey and Brady Haran have talked at length about scientific press conferences because what is reported to the media may not be an entirely accurate reading as to the actual discoveries being made.
Basically, the gist of this means that: I'll believe it when I see it.
And, my faith is generally in Magnetoplasmadynamic thrusters or Variable Specific Impulse Magnetoplasma Rockets.
In general any "exciting" science article should be cross checked with /r/science
quote: "Mars in 70 Days" is the usual indication that the article has been repeated/copied from clickbait sites. I think another is "Moon in 4 Hours". This might be a decent article, but they are hurting themselves with sensationalism. IMO. No builder I know of is even considering this feat. Too far down the road.
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Some of us appreciate seeing a simple, practical suggestion of what the significance could be. This is what good communication skills require.
The NASA scientists tried many kinds of tests to rule out the commonest attempts at explaining away the M-Drive (or em-drive). Their paper was published in a peer-reviewed journal. I hope there is a public announcement of the space test, when it occurs. If that test includes sending it off toward Mars, and it gets there in only 1/5 the time rockets would take, that would be COOL! Something to celebrate! We might actually send people to Mars after all! Not to mention return at last to the Moon in force!
One question I have is whether this M-Drive would be powerful enough to lift a vehicle off of the surface of the earth, or whether it would still be necessary to use rockets as a first stage. If effective enough to provide flight off the surface of the earth, then airliners could be completely redesigned, and would no longer need lengthy runways for takeoff and landing. Not to mention how much safer they would be, if they can hover like a helicopter, and take off and land vertically. Would aircraft carriers become obsolete? Would fences be enough to provide boundaries at national borders (sorry, Trump ).
[ December 08, 2016, 12:02 PM: Message edited by: Ron Lambert ]
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To me, the easiest way off the surface of the globe into orbit would be time travel...slow your relative speed to that of the Earth, and boom, you're in space!
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To be fair, Elison, this kind of propulsion has been on the radar for a while, with a whole lot of detractors, and this particular study seems pretty robust. I'm excited over it.
Perhaps we should wait for it to be reviewed by peers before we accept the Judgement of Reddit.
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quote:Originally posted by Stone_Wolf_: To me, the easiest way off the surface of the globe into orbit would be time travel...slow your relative speed to that of the Earth, and boom, you're in space!
quote:Originally posted by Heisenberg: To be fair, Elison, this kind of propulsion has been on the radar for a while, with a whole lot of detractors, and this particular study seems pretty robust. I'm excited over it.
Perhaps we should wait for it to be reviewed by peers before we accept the Judgement of Reddit.
Sure, but I just recall the various Hello Internet episodes about press conferences and I keep a pinch of salt handy.
Also we could easily get to Mars in 180 days for a pittance using off the shelf parts.
For the entire cost of the F-35 program we could be well on our way to a permanent manned presence on Mars with frequently 4x a year trips, already. We wouldn't need the Em Drive except as something to make something we were already doing *better*.
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I've honestly been looking at this from the outside in, and haven't paid TOO much attention to it.
Propulsion from microwaves in gravity. Isn't that, like, a pretty big deal? Breaking Newton's laws and all that?
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Generally speaking, I'm quite skeptical of signals so weak that you have to take heroic measures to separate them from noise. The more so when they would be such an immensely big deal.
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quote:Originally posted by Heisenberg: I've honestly been looking at this from the outside in, and haven't paid TOO much attention to it.
Propulsion from microwaves in gravity. Isn't that, like, a pretty big deal? Breaking Newton's laws and all that?
Again this is a part of the press conference discussion from HI, basically we could be having regular contact and communications with aliens and we wouldn't likely hear much of it because it would be through boring dry press conferences.
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As for the reported propulsive power output reported for the test device of 1.2 mN/kW, the N represents a Newton. According to Wikipedia: "One newton is the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in direction of the applied force."
m probably means milli, or one thousandth. kW of course means kilowatt, or thousand watts.
So the above means the force generated in the tests was 1.2 milliNewton, per kilowatt of power expended. Another way of saying it (someone better versed in math than I am correct me if I am wrong) is that the force generated was sufficient to accelerate 1.2 grams of mass at the rate of one meter per second squared at a power expenditure of one thousand watts. You would have to know the total mass of the system (vehicle) being accelerated--how many multiples of 1.2 grams--to say how much acceleration would be possible for the system (vehicle). Crucial here would be how small or light in mass the system (vehicle) could be made, and still produce the same output.
Remember the note about the new drive being two orders of magnitude greater than other propellant-less propulsion systems, such as light sails and lasers? While light sails would work--very, very slowly--no one has used them yet, even for our deep-ranging probes such as Voyager, because they provide a thrust that is so infinitesimally weak.
I wonder if use of superconductors somewhere in the system would improve the propulsive power output of the EmDrive.
I for one think it is cool that quantum physics seems to provide us with ways of cheating on the supposed "laws" of Newtonian physics (which really are not laws, just summaries of what we have observed to work consistently so far). But if the EmDrive (Shawyer Drive) really does work, then it is not science fiction, it cannot be dismissed as pseudoscience any more, and the future of space travel may be brighter than it has seemed for a long time!
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