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NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

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Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#81

Post by [deleted] »

roywiggins wrote: post #67
PaulAJ wrote: post #40

Earlier quoted context omitted.

> [..] while the electrical energy input only increases linearly with time. This is the fallacy. In an electric motor the power required to exert a force is proportional to the speed, so if you want to keep the acceleration constant you need to increase the electrical power (i.e. rate of energy use) linearly over time. Hence the total energy input increases with the square of the time, just like the kinetic energy im…

> proportional to the speed In what reference frame? It's not obvious to me how this works in a space drive. How does it "know" how much speed it gets per unit energy? I guess if it's a sort of Dean drive that swims through the gravitational field of the visible universe, then that's the reference frame. It's still weird!

[deleted]

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#82

Post by 0xffff2 »

azinman2 wrote: post #66
pmoriarty wrote: post #60

Earlier quoted context omitted.

That he made a mistake is much more plausible than that it was aliens. That he was hallucinating is much more plausible than that it was aliens. That he was lying or had a false memory is much more plausible than that it was aliens. Pretty much any mundane explanation is much more plausible than that it was aliens. Extraordinary claims require extraordinary evidence.

> Extraordinary claims require extraordinary evidence. Not in America these days...

Good thing we're talking about Spain in 1967 then. Why inject politics?

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#83

Post by TomSwirly »

nkoren wrote: post #52
sgt101 wrote: post #34

Earlier quoted context omitted.

Or a bird. Less high up, nice white tummy, reflects the light.

Do you honestly think that somebody trained in astronomy could mistake a bird for satellite? Have you seen how satellites move? They traverse the sky in a perfectly straight and constant-motion fashion that is utterly unlike any bird. Even a high-altitude plane such as the U-2 would be fairly difficult to misidentify as a satellite. For obvious reasons, U-2s and SR-71s and such didn't employ lights while operating at…

Absolutely, I think that it's much more likely that an astronomer made an observation error than he saw an alien spacecraft.

Extraordinary claims, etc.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#84

Post by [deleted] »

commonjcb wrote: post #13
imglorp wrote: post #9

Earlier quoted context omitted.

Wouldn't you want to run tests in multiple orientations to cancel Earth fields anyway? Similar to how you would run a Michaelson-Morley interferometer experiment.

The torsion balance introduces fixed biases, and can be operated only in XY plane. So in theory you're right, in practice it's not possible. Not canceling earth's magnetic field (an easy thing to do) when measuring microNewtons at high currents is just very poor experimental practice. Unprofessional. Amateur.

[deleted]

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#85

Post by marsokod »

imglorp wrote: post #9
commonjcb wrote: post #4

Not this shit again... Look closely at the picture of the test chamber in the article. Do you see Helmholtz coils surrounding the entire apparatus? Nope. https://en.wikipedia.org/wiki/Helmholtz_coil It's the same story as the EMdrive: they run something at high current, without cancelling earth's magnetic field. high current + earth magnetic field = force. This method is used to move satellites: https://en.wikipedia.…

Wouldn't you want to run tests in multiple orientations to cancel Earth fields anyway? Similar to how you would run a Michaelson-Morley interferometer experiment.

You could but that may be a bit complicated to set up, while Helmholtz coils are dead easy to make and install. It's just a frame, copper wires, 3 power supplies, a magnetometer and a PC (even an Arduino could drive it).

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#86

Post by slowmovintarget »

at_a_remove wrote: post #35
alkonaut wrote: post #18

Earlier quoted context omitted.

Did the EMdrive have a solid understanding of why it would work, rather than just being a discovered curious effect? What's interesting about this one is that there is a theory at least. Experiments aside, someone whould be able to either confirm or reject the theory on its own.

The EMdrive also had a "why." Note, if you investigate these sorts of devices, they typically have a why. It's just that the why tends to ignore a bunch of other things and it's a disappointment in the end. Really, if you're curious, you should dig into the history of all kinds of devices like these, anything in the Impossible Class. The inventor spends decades grinding away at it, getting inconsistent, odd little re…

This one relies on the premise that Einstein was right again. This is not unreasonable, especially given his track record.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#87

Post by mleonhard »

commonjcb wrote: post #4

Not this shit again... Look closely at the picture of the test chamber in the article. Do you see Helmholtz coils surrounding the entire apparatus? Nope. https://en.wikipedia.org/wiki/Helmholtz_coil It's the same story as the EMdrive: they run something at high current, without cancelling earth's magnetic field. high current + earth magnetic field = force. This method is used to move satellites: https://en.wikipedia.…

A 2013 paper by Fearn & Woodward makes no mention of the earth's magnetic field. After skimming the paper, I think their experiment is flawed.

"Experimental Null Test of a Mach Effect Thruster." https://arxiv.org/pdf/1301.6178.pdf

"The motion of the beam is damped by a pair of aluminum plates attached to the beam that move in the magnetic field of an array of small neodymium-boron magnets. The power circuit was extensively shielded to insure that stray fields did not compromise the results."

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#88

Post by perl4ever »

motohagiography wrote: post #47

So, I have to ask: If Elon Musk is working on propulsion tech to go to Mars, and Bob Lazar claims to have worked on reverse engineering propellentless tech and is one of the single digit number of living people to have encountered it directly, and NASA is slow rolling their own understanding of it, given the limited available expertise in this area how can Musk afford to not hire Lazar? From a due diligence perspecti…

>From a due diligence perspective, Musk would need to know with a high degree of certainty that Lazar is full of crap.

Surely people who know who Lazar is knew that in the 90s? Assuming they were alive then.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#89

Post by perl4ever »

shadowgovt wrote: post #49
jfengel wrote: post #36

Earlier quoted context omitted.

Even more than the funding, I hate the perpetual fueling of the narrative that magic is just around the corner. Why bother learning actual, boring science when a revolution is going to make everything different tomorrow, bringing us flying cars and gorgeous green Martian girls in steel bikinis? There's an enormous amount of science denial, at least in the United States. A lot of things go into that, but I don't think…

> the perpetual fueling of the narrative that magic is just around the corner Do you know why humans went to the moon in 1969? It wasn't just that people suddenly woke up one day and wanted to. The earliest known story of a voyage to the moon was written by Lucian of Samosata, CE 125. It wasn't that people woke up one day and were smart enough; the orbital mechanics were hard math, but the basics were understood sinc…

But it's a misunderstanding. I see things like this space drive as different, because they're supposed to be based on physics that hasn't been figured out.

Real revolutionary and amazing technology comes from physics that came way before, which in turn came from math that was even older.

Today people mostly can't imagine what the world was like, technologically and socially, a hundred years ago when relativity and quantum mechanics were on the cusp of being developed.

The things which will transform or devastate the world in the next few decades have been growing for the last 50 years even if most haven't noticed. It will look like coming out of nowhere, but it won't be in the way that this space drive is.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#90

Post by mleonhard »

pluto9 wrote: post #54
kaiju0 wrote: post #38

Earlier quoted context omitted.

Interstellar ships will be shaped like pencils to deflect rather than impact gasses. They will also have to have consumable nose cone sections with old ones in the front being removed and new ones installed at that back. Like a mechanical pencil.

What happens when the ship has to turn around to decelerate, with its engines facing the front?

The turn-around takes place at the half-way point of the journey. This means that for the entire second half of the journey, the engine is pointed at the oncoming dust.

Engines used in such long journeys will likely emit a thin stream of particles at extreme velocities. This stream is not wide enough or thick enough to stop space dust from hitting the engine. An unshielded forward-facing engine will get destroyed. So we must shield the engine.

Instead of having two shields and turning the ship around, just turn the engine around. Make the engine emit streams forward from the sides of the ship.

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