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The Physics of Why Cold Fusion Isn't Real

khallow Re:Why Cold Fusion (or something like it) Is Real (349 comments)

I apologize for that. I note though that Dr. Storms baldly asserts the claim that there are hundreds of such experimental attempts, a bunch of which are alleged to be successful with "large amounts" of power/heat produced (using his own book as sole reference). I can grant the former, since the attempts are public record. The successes though? I have to see more solid evidence of these than I've seen so far.

For example, the most successful experiment to date (Andrea Rossi's nickel-based LENR fusion) involves an experimental setup with plenty of opportunity for fraud and deception.

Meanwhile the experiments that Storm details are so marginal, that they attempt to determine the presence of fusion based on trace element analysis or correlation of high noise observations (like the ratio of estimated energy production to helium production). Reproducibility remains a huge problem throughout this work.

Don't get me wrong. Cold fusion most likely happens naturally just due to quantum tunneling. The whole point of these experiments is to create contrived situations where the quantum tunneling resulting in fusion happens far more often (many orders of magnitude more often, perhaps hundreds of orders of magnitude more often). Even if we are to eventually have highly successful cold fusion widely used for energy production and other uses, we'll still transition through this murky region of uncertain experimental evidence.

And it's worth noting here that despite whatever the American Physical Society or the US Department of Energy has said about cold fusion in 1989, research continues. They aren't really in the way now. I don't expect conservative, perhaps hide-bound institutions to embrace every new concept that comes along, even if in theory, that's their job.

2 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Get real (351 comments)

Here's the thing. What is valuable to you? Dumping lots of mass to the Moon? Or spending a few years extra? Operations (the cost of monitoring and planning an ongoing mission) tends to be rather cheap compared to R&D or the cost of deployment right now. The Moon in particular can host near real time teleoperations meaning that even if labor on the Moon is extraordinarily expense (or even non-existent), any such expedition can tap labor from Earth at vastly lower cost.

Further, there's probably a happy intermediate state where particularly difficult to manufacture, but very low mass stuff like ICs or components made under extreme conditions (like small high temp parts or exotic materials) can be shipped from Earth while most of the mass can be constructed on the Moon.

And it's worth noting here that there are already plans for making a basic machine shop from scratch. One needs to be able to construct a furnace and have access to sufficient metal. You can construct human operated machining tools from a lot less starting technology than what I'm proposing.

2 days ago
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Michigan Latest State To Ban Direct Tesla Sales

khallow Re:Great Job (255 comments)

Stop pretending it's some sort of aberration.

When you stop pretending your straw man represents some actual point of view. Libertarianism isn't entirely realistic, but then neither are the imaginary misrepresentations of it.

2 days ago
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What It Took For SpaceX To Become a Serious Space Company

khallow Re:Easy! Fraud.. (95 comments)

Who ya going to believe? Honest, trustworthy msmonroe who would never steer you wrong or your lying eyes?

2 days ago
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Ebola Does Not Require an "Ebola Czar," Nor Calling Up the National Guard

khallow Re:Maybe we need a Surgeon General (383 comments)

The US already has an acting Surgeon General. If this were really important to the Obama administration they could have found a candidate that would pass the Senate.

2 days ago
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The Largest Ship In the World Is Being Built In Korea

khallow Re:Ho-lee-crap (273 comments)

By supporting other Danish industries you ensure future goodwill

You do as well with South Korea. And when it comes to "goodwill" you have to ask what is going to come of that goodwill. Maersk will probably get screwed in Europe over the next few decades no matter which shipyard it uses. At least South Korea has reason to remember who threw them some business and humble enough to do something in kind.

I don't think it's just about money. I think it's also about actual capability to do the job on a fast schedule and goodwill.

2 days ago
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The Largest Ship In the World Is Being Built In Korea

khallow Re:Ho-lee-crap (273 comments)

The opposite of money is tribalism and there is nothing in between?

You're the only one proposing this claim. And since you don't take it seriously either, then maybe you shouldn't bother.

2 days ago
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A Look At Orion's Launch Abort System

khallow Re:Would this kind of system have saved Challenger (43 comments)

*sigh* This is one of the biggest pieces of misinformation about solid rockets floating about out there, spread and repeated by shuttle detractors in a cargo cult like fashion until it's now regarded as a law of nature. What most people (including engineers who should know better) don't realize is that you don't need to shut them down in the first place- you just need them to produce net zero thrust.

For "misinformation" it is quite correct, the booster is still burning even if it is producing net zero thrust. For example, if there is premature ignition of a solid rocket booster on the launch pad, then that SRBs will burn out no matter what you do with it, even if it is producing net zero thrust. And a launch pad isn't designed to hold a burning booster for several minutes even if it isn't producing net thrust.

I'm sure that NASA has thought this risk through entirely, but it is still there. The problem doesn't go away just because there is a means to make the booster produce no net thrust.

3 days ago
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The Largest Ship In the World Is Being Built In Korea

khallow Re:Ho-lee-crap (273 comments)

Price should not be the only metric to be used for measuring competitiveness. Supporting the society and industries that in turn support you should always be prioritized.

South Korea and its industries support Maersk too.

Unfortunately, stockholders only care about short-term savings and profits. No one dares to think in the long term, because that would mean slightly lessened profits in the short term.

What "long term" benefit is there with going with a Danish shipyard? What does that shipyard or Denmark itself offer than South Korea doesn't offer?

3 days ago
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The Largest Ship In the World Is Being Built In Korea

khallow Re:Ho-lee-crap (273 comments)

Consider it a huge warning. that your shipyards aren't competitive.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Solar insolation is 150,000 TW, we need 22 TW (351 comments)

Good point. And there wouldn't be significant additional transmission costs since the concept requires lots of long distance transmission capacity anyway. I think there would still be some need for storage in your scheme, but existing hydroelectric probably would be more than adequate.

5 days ago
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No More Lee-Enfield: Canada's Rangers To Get a Tech Upgrade

khallow Re: a quick search (331 comments)

Now imagine 3D printing bolt action rifles... in space. That's utopia right there.

5 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Replace rockets with something reasonable. (351 comments)

Some things just don't break down into little pieces in an economical fashion.

Then I guess we better focus in the near term on things that can be launched in small pieces. I'm not going to support, say, a 200 ton to orbit launch vehicle just because someone can think of peculiar payloads that a 20 ton vehicle can't launch. Capability != utility. We still have yet to have a reason for putting that 1000 ton NPR in orbit.

And I'll note that one can get decent performance out of a variety of competitive propulsion/powerplant combinations which can be broken down into small pieces.

Finally, if we are going to launch large unwieldy structures into space from Solar System bodies, then the Moon is a better place to do so, both because delta v is much smaller, but also because there is no atmosphere and hence, a much weaker restriction on fairing size (it just needs to be able to withstanding the acceleration of launch without damage). A near Earth asteroid might even be a better choice, especially if it can be moved to Earth orbit first.

about a week ago
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The Physics of Why Cold Fusion Isn't Real

khallow Re:Why Cold Fusion (or something like it) Is Real (349 comments)

Dr. Ramsey's condition has been fulfilled hundreds of times over the last quarter century and there has been absolutely no acknowledgement by the APS of its crime.

The first condition hasn't happened once much less hundreds of times, hence there is no "crime" for which the American Physical Society need acknowledge.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Baby steps (351 comments)

One could probably factory-produce a hundred Curiosity rovers and mass launch/land them in every corner of Mars for the cost of one manned mission

I'd say more like ten or so Curiosity rovers. Those things aren't that cheap and manned missions aren't that expensive.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Baby steps (351 comments)

Wouldn't that research have to be valuable first in order for the strategy to even have meaning? Look at the ISS. $100 billion burned so that we can do the same research that an oh, $5 billion MIR-class station could do. Further, the research isn't worth stealing even if it weren't all open in the first place.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Solar insolation is 150,000 TW, we need 22 TW (351 comments)

but 22 TW could be captured using very little acreage

For an hour around noon. You would need more plus storage to make a viable system that provides energy even when the Sun isn't shining.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Get real (351 comments)

Well, I recall the price of reaching the Moon about ten years ago was considered to be $100k per kg and Mars was ten times that much. I was basing my estimate off that recollection.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Get real (351 comments)

You need way more than that to have ISRU equipment *and the in-place industrial capacity to maintain it*.

Sure. That's why you use ISRU so that the Moon's resources provides most of that mass.

Do yourself a favor and walk through a machine shop attached to a college lab or a chemical plant or something and do a mass budget before you start declaring stuff feasible with current tech for reasonable cost.

I already have. All those machines can be scaled down. You could probably put a full spread of basic machine shop tools (forge, lathe, mill, press, 3D printer, etc) up there for tens of kilograms. You can then on the Moon build larger versions to do real world machine shop stuff. It's not fast like dumping hundreds of tons of stuff on the Moon, but it gets around the need for lots of mass from Earth.

about a week ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

khallow Re:Replace rockets with something reasonable. (351 comments)

Launching something huge - for example, anything even close to the size of the ISS, much less anything bigger - will require either an extraordinary breakthrough in rocketry or a completely new launch system.

No, it doesn't. The ISS wasn't launched or assembled that way and any other large space station isn't going to be launched in one piece either. Existing rockets can easily launch something like the ISS, piece by piece.

And the price of putting something in orbit has already dropped a considerable amount. Shuttle was crazy expensive, I gather something like $20k per kg for an optimal payload. Falcon 9 is something like $3k per kg.

Further, chemical rockets make a great technological stepping stone to other launch technologies. First, they can create and prove a market for fancier infrastructure. You don't have to do the "build it and they will come" assumption, hoping that your space elevator or whatever will have enough business to justify its existence when there's a thriving rocket market to point to.

They also can be used to launch the initial infrastructure you may need for other approaches or launch stuff that increases demand for more launch infrastructure.

about a week ago

Submissions

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Cheap airship sets new record for altitude

khallow khallow writes  |  more than 2 years ago

khallow writes "Last weekend, we saw balloons beat records for the highest amateur balloon and longest latex balloon flight by distance and duration, but another record was broken as well. JP Aerospace, a team operating out of Sacramento, California (but supported by members all over the world) launched an operating airship to 95,085 feet (almost 29 kilometers high). Space.com had this to say:



Crewed stations floating high above the Earth with huge balloons could someday act as waypoints for human astronauts headed into space. That's the vision of a DIY space program that has smashed world altitude records by sending a drone airship flying up 18 miles into the sky. The Tandem airship soared almost four miles higher than any past airships during its record-breaking flight on the morning of Oct. 22. Its flight to 95,085 feet above Nevada's Black Rock desert marks a first step toward plans for an "Airship to Orbit" program that would fly humans into space using existing technology.

"The big aerospace firms have been trying to do this for decades, spending hundreds of millions of dollars," said John Powell, president of JP Aerospace. "We've spent about $30,000 and the past five years developing Tandem."

"

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