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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

#91

Post by mcswell »

Nit: "as Newton put it, inertia is why an object at rest tends to stay at rest." No, what Newton said is that an object in motion tends to continue in motion at the same velocity (and an object at rest tends to remain at rest, i.e. with velocity=0).

While this doesn't have a lot to do with the original article (hence my "nit"), it was revolutionary at Newton's time. People had observed objects at rest staying there; that's why you can sit on a chair. But they had also observed that any object in motion (except for those in the sky) slowed down and eventually stopped, unless you kept pushing them. Newton attributed this to friction.

This theory--which contradicted what people could plainly observe with their eyes--is what makes possible satellites (and keeps the moon in orbit), since being outside the atmosphere, they experience very little friction. Of course the other thing necessary for man-made satellites is a way to get them moving fast enough, for which Newton's third law comes in handy (it's why rockets accelerate, even outside the atmosphere).

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#92

Post by snowwrestler »

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…

The SR-71 cruised on afterburners, which produce light. Not sure if it was bright enough to be seen on the ground, though.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#93

Post by Johnythree »

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…

> Have you seen how satellites move? They traverse the sky in a perfectly straight and constant-motion fashion

Except this one didn't.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#95

Post by strombye »

cwhiz wrote: post #24
AnIdiotOnTheNet wrote: post #17

Earlier quoted context omitted.

People don't like to see quack science take funding from legitimate science. I am not qualified to judge whether or not this is quack science, but it certainly reeks of the same claims as previously documented quack science.

I believe a total of $620,000 over a span of several decades. I am personally quite happy to fund one-off random projects like this. The amount of money is a trivial rounding error. Funding 100,000 failures at this level would be worth it if one, just one, worked. I do understand that others might think differently. I like moonshots.

Would you give me $620,000 in pennies to throw in a wishing well? If one wish comes true, it’ll be worth it!

That’s what this is like. It’s not a long shot, it’s guaranteed failure.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#96

Post by jp555 »

jccooper wrote: post #75
at_a_remove wrote: post #19

Earlier quoted context omitted.

It is because the payoffs would be so enormous that business like this and "overunity motors" continue to gain attention. All of those other elixirs were shams, but this one will work! Finally, immortality! The enormity of the reward causes the payout matrix to lead people astray. Don't get me wrong, I see a vacuum chamber, which is light years ahead of most of these enterprises, but I would not spend a dime on it un…

Propellant-less propulsion within the confines of Earth's magnetic field or gravity well is still pretty valuable. The entire space economy at the moment is Earth satellites, all of which are constrained by propellant.

Being able to build boxes that are bigger on the inside than on the outside would also be very valuable - like a standard 40ft shipping container that fits in your pocket.

And that's very close to the kind of thing we're talking about here.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#97

Post by vidarh »

cwhiz wrote: post #24
AnIdiotOnTheNet wrote: post #17

Earlier quoted context omitted.

People don't like to see quack science take funding from legitimate science. I am not qualified to judge whether or not this is quack science, but it certainly reeks of the same claims as previously documented quack science.

I believe a total of $620,000 over a span of several decades. I am personally quite happy to fund one-off random projects like this. The amount of money is a trivial rounding error. Funding 100,000 failures at this level would be worth it if one, just one, worked. I do understand that others might think differently. I like moonshots.

Put another way: modern chemistry is in many ways a descendant of alchemy. It's the outcome of people pursuing ultimately failing experiments but identifying other interesting things along the way. It laid the foundation for laboratory practices and uncovered a lot of the basics.

Even if all of these experiments fail, chances are some of them will come across findings that are useful in unexpected ways.

If nothing else falsifying these theories will help create a baseline of effects that needs to be accounted for in the investigation of future theories like this.

Re: NASA Funded Scientists Claim Breakthrough in Propellantless Propulsion

#98

Post by Aesthetys »

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.…

I’ve never understood this position with the EMdrive and similar technologies; wouldn’t magnetic propulsion revolutionize low-earth-orbit travel, or whatever the ceiling is for pushing against Earth’s magnetic field?
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