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Uncertain Propulsion Breakthroughs?

centauri-dreams.org

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Re: Uncertain Propulsion Breakthroughs?

#3
tl;dr;

> First, I cannot stress enough that there is no new EmDrive “effect” yet about which to theorize. The physical evidence on the EmDrive is neither defensible nor does it include enough operating parameters to characterize a new effect. The data is not even reliable enough to deduce the force-per-power relationship, let alone any other important correlations.

Re: Uncertain Propulsion Breakthroughs?

#5
post #3

tl;dr; > First, I cannot stress enough that there is no new EmDrive “effect” yet about which to theorize. The physical evidence on the EmDrive is neither defensible nor does it include enough operating parameters to characterize a new effect. The data is not even reliable enough to deduce the force-per-power relationship, let alone any other important correlations.

I don't think that's a fair summary... The author provides a more nuanced view than just "there is no effect." You're nitpicking from one section about theory, without considering the article as a whole. This is especially egregious considering that the article spends so much time talking about confirmation bias.

Re: Uncertain Propulsion Breakthroughs?

#6
post #4

I know Marc Millis, let me know if anyone has any questions and I can try to get his feedback here.

He did so partially in this article, but I would love to see a detailed explanation of a valid experimental setup to test the EmDrive effect. What would an experiment look like where, if thrust were observed, then we could really start to say there might be something here?

Re: Uncertain Propulsion Breakthroughs?

#7
It's so near the noise threshold. Most of the energy goes into heating the thing; only a tiny fraction comes out as possible thrust. The heating prevents using enough power to get more possible thrust; the thing would burn out.

Very frustrating.

Re: Uncertain Propulsion Breakthroughs?

#8

I hope we'll find out in practice: http://www.popularmechanics.com/science/energy/a22678/em-dri... (via lobster_johnson) "Proud to say that we have a partnership now - so the launch is already funded, and we hope to get a launch slot in 2017."

Being in space doesn't solve the problem of errant forces completely. You can push against the earth's magnetic field, for example.

Re: Uncertain Propulsion Breakthroughs?

#10
post #8

I hope we'll find out in practice: http://www.popularmechanics.com/science/energy/a22678/em-dri... (via lobster_johnson) "Proud to say that we have a partnership now - so the launch is already funded, and we hope to get a launch slot in 2017."

Being in space doesn't solve the problem of errant forces completely. You can push against the earth's magnetic field, for example.

Satellite orbits degrade overtime due to drag, among other things [1]. Operators counter this decay with periodic boosts. (The International Space Station is boosted, on average, once a month [2].) Boosting, even electric propulsion boosting, consumes propellant.

If this works by impelling against the Earth's magnetic field, provided it is more efficient than a simple magnet, it could still have a market with satellite manufacturers.

[1] https://en.wikipedia.org/wiki/Orbital_decay

[2] http://space.stackexchange.com/questions/9087/how-often-does...

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