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posted by janrinok on Friday August 01 2014, @08:49PM   Printer-friendly [Skip to comment(s)]
from the it-shouldn't-work-but-does dept.

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"

Related Stories

It's Official: NASA's Peer-Reviewed EmDrive Paper Has Finally Been Published 133 comments

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


Original Submission

"Reactionless" Thruster Tested Again, This Time in a Vacuum 62 comments

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?

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  • (Score: 3, Informative) by LaminatorX on Friday August 01 2014, @08:52PM

    by LaminatorX (14) <reversethis-{moc ... ta} {xrotanimal}> on Friday August 01 2014, @08:52PM (#76534)

    The real test will be whether it works outside the Earth's magnetic field. A lot of these sorts of "inexplicable" devices end up obeying conservation rules by degrading their own magnets, basically harvesting energy stored during the magnet's manufacture and leaving the magnets electrons in a less ordered state. If this thing were placing a minute drag on the spin of the Earth's core to balance the equations, I doubt we'd be able to detect it.

    • (Score: 2) by mhajicek on Friday August 01 2014, @11:24PM

      by mhajicek (51) on Friday August 01 2014, @11:24PM (#76577)

      How long till the Kerbal mod for it comes out?

      --
      The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
    • (Score: 3, Interesting) by mcgrew on Saturday August 02 2014, @02:12AM

      by mcgrew (701) <publish@mcgrewbooks.com> on Saturday August 02 2014, @02:12AM (#76615) Homepage Journal

      I'm skeptical as well.

      Back in the 90s, Nasa tested what was claimed to be an antigravity device based on spinning superconducting discs. That was reported to give good test results, until researchers realised that interference from the device was affecting their measuring instruments. They have probably learned a lot since then.

      However:

      The torsion balance they used to test the thrust was sensitive enough to detect a thrust of less than ten micronewtons, but the drive actually produced 30 to 50 micronewtons -- less than a thousandth of the Chinese results, but emphatically a positive result, in spite of the law of conservation of momentum

      I'd like to see it tested in space as well, and if NASA thinks it really is viable I'm sure it will be on a rocket sometime headed outside the magnetic field for testing. It could ride piggyback with some other instrument; we have a lot of scientific equipment outside the magnetic field already and there will surely be plenty more.

      But I don't see how it would violate the laws. It isn't like perpetual motion; you're not getting free anything with this, you have to feed it electrical energy which it allegedly converts to kinetic energy. Personally, I prefer ion propulsion.

      If it does work, imagine a vessel with them in huge arrays fed by fusion generators!

      --
      Free Martian whores! [mcgrewbooks.com]
      • (Score: 2) by maxwell demon on Saturday August 02 2014, @11:42AM

        by maxwell demon (1608) on Saturday August 02 2014, @11:42AM (#76696) Journal

        The point is that it would, according to the article, violate conservation of momentum. Just because it doesn't violate the laws of thermodynamics doesn't mean it doesn't violate any laws of physics.

        Well, actually, if it indeed works, it quite obviously doesn't violate the laws of physics; however, we might then have to update our idea about what the laws of physics are.

        --
        The Tao of math: The numbers you can count are not the real numbers.
        • (Score: 4, Insightful) by DrMag on Saturday August 02 2014, @02:57PM

          by DrMag (1860) on Saturday August 02 2014, @02:57PM (#76722)

          Speaking as a genuine physicist, my biggest pet peeve of the science world is that while non-scientists misunderstand what is meant by "theory", scientists mis-understand (or at least mis-construe) the meaning of "law". Laws in science are not like laws in government, though sometimes they can be as arbitrary. A scientific law is simply a mathematical equation that describes some process--nothing more, nothing less. There is nothing that requires a scientific law to be correct, or have any bearing in reality. As a result, the laws of the game of science can be as meticulous as chess, or as crazy as Calvin ball. Though often I feel like they are now so convoluted that, along with the degree of obsession people have over them, it feels more like D&D.

          There are three things I wish everyone understood better: statistics, compassion, and the fallibility of all fields. We'd all be much better off if our response to statements like this were, 'Huh, that's interesting... How can we test this?' rather than turning up our nose at and ignoring any idea that doesn't fit perfectly into our particular mindset.

        • (Score: 2) by metamonkey on Saturday August 02 2014, @02:58PM

          by metamonkey (3174) on Saturday August 02 2014, @02:58PM (#76723)

          While I think there are many other things that could have generated the measured force (pushing against the air in the chamber? It wasn't a vacuum. Maybe it created an electromagnet and pushed against earth's magnetic field?), if it does work it still conserves momentum. They think it was pushing against the vacuum quantum plasma, the virtual particles that continuously pop in and out of existence even in vacuum. If so, the virtual particles become the propellent, accelerated away from the drive, providing thrust. Momentum is conserved.

          --
          Okay 3, 2, 1, let's jam.
        • (Score: 3, Informative) by mcgrew on Saturday August 02 2014, @03:22PM

          by mcgrew (701) <publish@mcgrewbooks.com> on Saturday August 02 2014, @03:22PM (#76730) Homepage Journal

          Yes, the article points that out but adds that much having to do with particle physics seems to violate Newtonian laws while following relativistic laws. This seems to work on the principle that waves added in phase with each other double amplitude, while waves added out of phase cancel them out, making it only seem to violate conservation of momentum without actually doing so.

          --
          Free Martian whores! [mcgrewbooks.com]
      • (Score: 5, Informative) by metamonkey on Saturday August 02 2014, @02:55PM

        by metamonkey (3174) on Saturday August 02 2014, @02:55PM (#76721)

        Nobody's saying it's free energy. What's interesting about it is that it provides thrust without propellant. The only way to move in space (besides solar sails) is to throw something in the opposite direction of your desired travel. We generally do this violently, with rocket engines. Even the ion drive you like uses propellent. It works by excitation of the electric field, accelerating an ion (generally xenon) and propelling it out the back.

        What would be neat about this, if it worked, is that you wouldn't have to carry propellent, just fuel to generate electricity (or solar panels). That's huge, because the mass of the propellent is the real limiting factor on how fast we can move through space. The faster you want to go, the more propellent you have to carry, and the more propellent you have to carry, the more propellent you need, etc, etc. And then you have to carry all the propellent you need to slow down.

        If this works, it would basically be using vacuum quantum plasma as the propellent. The microwaves bounce around in the chamber and push against the particles that spontaneously pop in and out of existence. Momentum would still be conserved.

        However, this test doesn't seem conclusive. First, they didn't even have a vacuum in the test setup. They had it in a vacuum chamber, but it was at atmospheric pressure. Ummmmm maybe it was pushing off, I don't know, the air? It's also in Earth's magnetic field. Perhaps it just created an electromagnet and pushed against Earth's magnetic field. Also, they built another machine that was supposedly designed to *not* produce thrust, and yet it did. Something weird is going on here, but it's a big leap to say "Oh, it must be pushing against vacuum quantum plasma!"

        More study is needed. First produce thrust in a vacuum. If that still works, do it away from the Earth's magnetic field. Then we're talking. If that works, then...damn depending on the efficiency, a real reactionless drive can get you to the stars. A small but constant acceleration will eventually get you a significant fraction of the speed of light, without needing to accelerate the mass of propellant needed to accelerate and decelerate.

        --
        Okay 3, 2, 1, let's jam.
  • (Score: 2) by MrGuy on Friday August 01 2014, @09:00PM

    by MrGuy (1007) on Friday August 01 2014, @09:00PM (#76537)

    Favorite quote from TFA:
    Back in the 90s, Nasa tested what was claimed to be an antigravity device based on spinning superconducting discs. That was reported to give good test results, until researchers realised that interference from the device was affecting their measuring instruments. They have probably learned a lot since then.

    Um....probably?

    There's zero evidence supplied to back up the claim that NASA has learned anything from previous failures. They don't describe in TFA any methodological or philosophical differences from the antigravity failure. Just a statement of "hey, these guys have been wrong in the past, but maybe they're not this time!"

    • (Score: 2) by buswolley on Friday August 01 2014, @09:05PM

      by buswolley (848) on Friday August 01 2014, @09:05PM (#76539)

      They state no evidence whatsoever that that scenario applies to this scenario. So, ok.

      --
      subicular junctures
    • (Score: 0) by Anonymous Coward on Friday August 01 2014, @11:35PM

      by Anonymous Coward on Friday August 01 2014, @11:35PM (#76579)

      There's zero evidence supplied to back up the claim that NASA has learned anything from previous failures.

      Yeah, there is:they're outsourcing the next space shuttle instead of attempting to do it themselves again.

  • (Score: 3, Funny) by bob_super on Friday August 01 2014, @09:02PM

    by bob_super (1357) on Friday August 01 2014, @09:02PM (#76538)

    I'm pretty sure some B-series sci-fi movie must have a copyright on "quantum vacuum virtual plasma"

    • (Score: -1, Troll) by Anonymous Coward on Friday August 01 2014, @10:05PM

      by Anonymous Coward on Friday August 01 2014, @10:05PM (#76553)

      I'm gonna need to change underwear which just got sticky!

      • (Score: 3, Funny) by Subsentient on Friday August 01 2014, @10:39PM

        by Subsentient (1111) Subscriber Badge on Friday August 01 2014, @10:39PM (#76562) Homepage Journal

        Stop filling your catheter with grape jelly.

        --
        "It is no measure of health to be well adjusted to a profoundly sick society." -Jiddu Krishnamurti
  • (Score: 5, Insightful) by PinkyGigglebrain on Friday August 01 2014, @09:38PM

    by PinkyGigglebrain (4458) on Friday August 01 2014, @09:38PM (#76547)

    As I understand this device it would not violate any of the laws of thermodynamics, you have to pump energy into it to get it to work and you don't get more energy/thrust out.

    It does cause issues with Newtonian conservation, the whole action/reaction part. But then this wouldn't be the first time Newtonian "Laws" have broken down when applied to things that special relativity and quantum theory explain much better.

    EM radiation has an interesting characteristic in that there is a point in the wave propagation where all the energy hits zero potential before swinging back on the other side of the axis. There are lots of claims about getting "Free energy" out of this zero point, those violate conservation and thermodynamics.

    According to what I read about this device a few years ago it uses a cavity that has been tuned so at one end the microwaves reflect off it when the wave is at the zero potential state and is at full energy when it reflects off the other end of the cavity. It provides the push in the direction of the full energy side.

    Maybe it doesn't even violate the "Laws of motion" at all, the reaction part might be happening in another set of dimensions. Last I heard Quantum theory claims 11 dimensions.

    China has been researching this tech for years, and now NASA says they might have found something.

    At the very least they should continue to look into it until they can conclusively invalidate/validate the effect. And back it up with more than a "Physics says it shouldn't work so it doesn't" response.

    Hell, maybe they found a way to harness Dark Energy without even realizing it.

    And now for all the rebuttals by people who "know better" because modern physics is perfect and already explains everything.

    --
    "Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
    • (Score: 1, Flamebait) by hubie on Friday August 01 2014, @10:11PM

      by hubie (1068) Subscriber Badge on Friday August 01 2014, @10:11PM (#76555) Journal

      Or, maybe, it is all measurement error and there is nothing to it. If there is something new here it will be turned up because there is scientific fame and glory to be had. However, it it turns out to be a small effect that is largely non-reproducible, it will be tossed on the heap of curiosities that never panned out.

      And now for all the rebuttals by people who "know better" because modern physics is perfect and already explains everything.

      Wow. Nice broad brush you're using there. I guess any criticism will come from obvious "physics shills" then? Maybe wanting to keep down the little guy, trying to cover up the truth because it is a threat to their funding somehow?

      • (Score: 3, Informative) by choose another one on Friday August 01 2014, @11:08PM

        by choose another one (515) Subscriber Badge on Friday August 01 2014, @11:08PM (#76568)

        However, it it turns out to be a small effect that is largely non-reproducible

        It is a bit past that already. First designed and tested in the UK, effect reproduced in China, and now reproduced again by NASA - different experiments with different kit, all showing the effect.

        What still isn't clear is how exactly it works, and how to tune it and scale it.

        • (Score: 3, Interesting) by hubie on Saturday August 02 2014, @12:51AM

          by hubie (1068) Subscriber Badge on Saturday August 02 2014, @12:51AM (#76594) Journal

          The NASA results, at least the little bit that one can gleam from their conference summary, are underwhelming in their magnitude and I would worry about a problem with their experimental setup. The Chinese result is rather large and is on the order of what you get out of an ion drive; if those results are good they should be relatively easy to replicate.

          • (Score: 2) by PinkyGigglebrain on Saturday August 02 2014, @02:42AM

            by PinkyGigglebrain (4458) on Saturday August 02 2014, @02:42AM (#76626)

            The NASA design is different from the device used in the China tests. The difference in measured thrust might be because NASA did a better job accounting for all the factors and the device really does only generate such a tiny amount of thrust, or NASA's device might not have been as evolved and the Chinese device really did generate the greater thrust.

            Either way three different independent groups have found something and currently no one can say exactly what.

            What was considered impossible just 60 years ago is no commonplace, its all about advancing technology and our understanding of how nature works. This might just be a flash in the pan or it might be the key to a new understanding of the Universe.

            --
            "Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
    • (Score: 2) by JoeMerchant on Saturday August 02 2014, @01:40AM

      by JoeMerchant (3937) on Saturday August 02 2014, @01:40AM (#76606)

      What I wonder is why something like this hasn't been validated, or at least tested, on the ISS?

      --
      Україна не входить до складу Росії.
      • (Score: 3, Insightful) by PinkyGigglebrain on Saturday August 02 2014, @07:03AM

        by PinkyGigglebrain (4458) on Saturday August 02 2014, @07:03AM (#76669)

        sorry if this is a dup, I had to leave in a rush and may have forgotten to hit submit before closing my browser last time.

        the per kilo cost of putting something into orbit is so high that they would want to really be sure it was worth sending a prototype to the ISS.

        --
        "Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
    • (Score: 0) by Anonymous Coward on Saturday August 02 2014, @08:24AM

      by Anonymous Coward on Saturday August 02 2014, @08:24AM (#76679)

      EM radiation has an interesting characteristic in that there is a point in the wave propagation where all the energy hits zero potential before swinging back on the other side of the axis.

      This sentence is enough to tell us you know nothing about EM radiation or Maxwell's Equations. This is on the same level as the Dilbert strip where Dilbert told his PHB because the lan cable got loose, the token had fell out of the Token Ring network, and it can't be fixed until the PHB finds the token in his office. i.e. total bullshit.

      Just because you have heard stuff about science that you don't understand, doesn't mean any BS is valid science. And sadly, your post got modded up to +5 told us most Soylentils knew nothing about Maxwell's Equations either.

      tuned so at one end the microwaves reflect off it when the wave is at the zero potential state and is at full energy when it reflects off the other end of the cavity

      Classically (i.e. within non-quantum theory), EM radiation is a wave little different from water wave on any water surface, if the above is possible, then you can do the exact same setup with a tank of water on wheels, so the wave is flat on one side and peaked on the other side, and drive the tank to move without any other mechanism (i.e. no drive to the wheels, no material ejection, doesn't push on anything outside the tank). Obviously, you are not going see that demonstrated any time soon.

      And now for all the rebuttals by people who "know better" because modern physics is perfect and already explains everything.

      Yeah, what a great way to stop intelligent debate by first deriding anyone who possibly know more than you as people who "know better".

      But don't worry, I am sure my explanation above would be beyond you ability to comprehend, so you can simply dismiss that as something from someone who "know better" and thought modern physics already explains everything, and happily go back to your ignorant demon-haunted world.

  • (Score: 3, Insightful) by wonkey_monkey on Friday August 01 2014, @09:52PM

    by wonkey_monkey (279) on Friday August 01 2014, @09:52PM (#76550) Homepage

    Two things are of note, as best as I have gathered as this story unfolds:

    Firstly, NASA tested two devices. One was the working device, the other was a device deliberately changed so as not to produce thrust. The problem is, they detected the same amount of thrust from both devices.

    Secondly, the test wasn't done in a vacuum. As I recall, there was a similar brief debacle when everyone was clamouring that lifters [wikipedia.org] were anti-gravity devices, because they'd been tested in a vacuum - the problem there was that the vacuum wasn't hard enough. Once you expelled all the air, they failed to function.

    This test wasn't even done in a partial vacuum, as I understand it.

    --
    systemd is Roko's Basilisk
    • (Score: 3, Informative) by DrMag on Saturday August 02 2014, @03:11PM

      by DrMag (1860) on Saturday August 02 2014, @03:11PM (#76727)

      I have seen others offer a quote from the paper:

      After sealing the chamber, the test facility vacuum pumps are used to reduce the environmental pressure down as far as 5x10E-6 Torr. Two roughing pumps provide the vacuum required to lower the environment to approximately 10 Torr in less than 30 minutes. Then, two high-speed turbo pumps are used to complete the evacuation to 5x10E-6 Torr, which requires a few additional days.

      The full paper is here [aiaa.org], but I don't have access to it from where I am now. I'll have to verify the quote when I get back to work next week. I think the confusion is from the abstract [nasa.gov], which states that they did a test at ambient pressure, but says nothing about the other test configurations. I may certainly be wrong, but I doubt that a NASA team would fail to test this in vacuum before presenting like this.

      • (Score: 2) by DrMag on Monday August 04 2014, @02:19PM

        by DrMag (1860) on Monday August 04 2014, @02:19PM (#77213)

        Ok, now that I'm at work I've had a chance to read through the paper. The quote is valid, though to be fair it is in the description of the vacuum chamber capabilities, which is not necessarily the same as the setup used in the test. However, nothing in the paper suggests they did not, so either it's a gross omission, or they did tests at vacuum.

        In either case, they are planning a new design that they expect to be an order of magnitude better (0.1 N per kW), with an added feature to rule out another possibility I hadn't remembered to consider:

        The [new] tapered thruster has a mechanical design such that it will be able to hold
        pressure at 14.7 pounds per square inch (psi) inside of the thruster body while the thruster is tested at vacuum to
        preclude glow discharge within the thruster body while it is being operated at high power.

  • (Score: 3, Interesting) by hubie on Friday August 01 2014, @09:54PM

    by hubie (1068) Subscriber Badge on Friday August 01 2014, @09:54PM (#76551) Journal

    They claim to have measured 30-50 micro-Newtons. They also appeared to have tested it in a steel chamber at ambient pressure (not a vacuum), and it is using a microwave source. First off, micro-Newtons is tiny. Then if you are measuring a tiny signal while you're blasting microwaves out in a metal chamber, they are asking for EMI (electromagnetic interference) problems. I have a lot of skepticism, but unfortunately the conference paper is not available to me (it is a paper for an AIAA conference, and unless you're an AIAA member, forget about getting a copy (I'm even a co-author on an AIAA paper and it was a pain for me to get a copy)).

    Unfortunately, the article shows a picture of the EmDrive, not the one tested for this paper. If they are comparable size, the picture shows it to be a decent size. I would need to read their paper, but given what they measured under the conditions they described, I would be very reluctant to throw around words like "validated" or "confirmed." The Chinese results claim 720 milli-Newtons, which should be much easier to verify. Too bad they didn't use the same thruster the Chinese used.

    • (Score: 0) by Anonymous Coward on Friday August 01 2014, @10:24PM

      by Anonymous Coward on Friday August 01 2014, @10:24PM (#76557)

      That is one of the things I've long noted about NASA - that they keep hiring these guys who don't know what they're doing.

      • (Score: 0) by Anonymous Coward on Saturday August 02 2014, @12:24AM

        by Anonymous Coward on Saturday August 02 2014, @12:24AM (#76587)

        That and their funding problems are more the fault of Congress than NASA.

    • (Score: 0) by Anonymous Coward on Sunday August 03 2014, @03:24AM

      by Anonymous Coward on Sunday August 03 2014, @03:24AM (#76828)

      that's 72 grams from 2.5kw.

      1.21 jiga watt thrust vectoring and my quad racer is set.

    • (Score: 2) by VLM on Sunday August 03 2014, @11:46AM

      by VLM (445) Subscriber Badge on Sunday August 03 2014, @11:46AM (#76875)

      "First off, micro-Newtons is tiny."

      How tiny?

      Right off the top of my head its an appropriate measure for sunlight pressure for a medium-ish sized spacecraft. Depending on geometry and orbit (like orbit of Mercury or orbit of Neptune?) etc. Light pressure is well understood physics. The point of this experiment is screwing around with a different wavelength of EM waves. Whatever. So if it worked you're not going to the stars as designed currently, but it migth help with stabilization of large solar panel arrays. Other than I think we have a scaling problem here.

      Another thing best measured in micro-newtons is some really small ion thrusters recently developed for some scientific experiment I don't remember. It turns out to be really hard to both generate and measure and control a force this small. It should be possible scientifically but its an area of engineering that has not as of yet been deeply explored. So even if its useless for "real propulsion" it might be handy for weird cutting edge scientific experiments.

      Another thing I can think of that screws around in micro-Newton level is gravity of "human industrial objects". A couple thousand pounds of junk vs a couple hundred pounds of junk at a close-ish range is sorta on the scale of micronewtons. Yeah yeah 10 Kg 10 M apart is like a nanonewton which is a thousandth too small. Luckily things can be closer together than 30 feet and industrial objects can be way heavier than a thousand times a kilogram. The biggest unit object I ever had access to (although as IT guy, I never used) was an industrial metal lathe about 100 feet long by 10 feet high used to build crane shafts or some such thing and as a rough estimate the gravitational force between me and that lathe could be reasonably expressed in micronewtons.

      If you want to play angular games for fun, run the trig analysis of if I weigh a reasonable amount of newtons and my feet are a foot apart, then micro newtons to the left or right represent one foot being a ridiculous amount higher or lower than the other foot. Estimate in my head well below the thickness of a piece of paper. So any measurements require much better than "ah its just kinda flat looking" or "Seems level cause it's kinda lined up with pix on the wall"

      A final micro-newton scale situation I can think of would revolve around sound. I'm having a hard time estimating based electrically making some assumptions about speaker efficiency (which is never as high as people think) but I think micronewtons of force on the speaker in my subwoofer would be quite inaudible across the room yet micronewton forces on the speaker in my mother in law's hearing aid in her ear "could be" audible plus or minus the reason she's wearing the hearing aide. I think it would be out of thermal noise range but not entirely sure.

      I'm just trying to take the measurement outta technobabble land and into "and this is why its an engineering challenge to measure" land.

      Check out:

      http://demonstrations.wolfram.com/GravitationalForceBetweenTwoSpheres/ [wolfram.com]

  • (Score: 0) by Anonymous Coward on Saturday August 02 2014, @01:03PM

    by Anonymous Coward on Saturday August 02 2014, @01:03PM (#76702)

    ..there is.
    nevertheless it reads like a prison break from the mechanically governed slave planet called earth!

  • (Score: 0) by Anonymous Coward on Sunday August 03 2014, @03:13AM

    by Anonymous Coward on Sunday August 03 2014, @03:13AM (#76827)