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Comment Re:Cost of access is key. (Score 1) 284

The salary/indemnification for the position is their own personal money, yes, and then they are supposed to be able to spend it however they like without oversight. Taxpayer money tapped according to financing laws to pay for government projects, however, is an entirely different thing (in theory).

Comment Re:Cost of access is key. (Score 1) 284

The amount of provisioning and boat building required would indicate at least local levels of cooperation and contribution that would most likely be analogous to modern government sponsorship of exploration and colonization. These aren't the brave, rugged capitalist individualists you are looking for, either.

The ignorance is deafening here. Do you even know how tribes work ? Read anything about what a Big Man is ? How they stimulate cooperation and contribution into collective projects, in a transactional way ? Those are proto-entrepreneurs, they buy cooperation from the rest of the people with gifts from their own overproduction (can I call these 'savings' ?), and reap prestige and influence from the success of the projects they set in motion (or infamy if it turns out badly).

Comment Another useful vacuum tube: Thermionic converter. (Score 1) 93

Another vacuum tube technology with current applications and substantial advantages over semiconductor approaches to the same problems is the Thermionic Converter. This is a vacuum-tube technology heat engine that turns temperature differences into electric power - by boiling electrons off a hot electrode and collecting them, at a somewhat more negative voltage (like 0.5 to 1 volt), at a cooler electrode.

Semiconductor approaches such as the Peltier Cell tend to be limited in operating temperature due to the materials involved, and lose a major fraction of the available power to non-power-producing heat conduction from the hot to the cold side of the device. Thermionic converters, by contrast are vacuum devices, and inherently insulating (with the heat conducted almost entirely by the working electrons, where it is doing the generation, or parasitic infrared radiation, which can be reflected rater than absorbed at the cold side.) They work very well at temperatures of a couple thousand degrees, a good match to combustion, point-focused solar, and nuclear thermal sources.

Thermionic converters have been the subject to recent improvements, such as graphine electrodes. The power density limitation of space charge has been solved, by using a "control grid" to encourage to charge to move along from the emitter to the collector and magnetic fields to guide it (so it doesn't discharge the control grid and waste the power used to charge it).

Current thermionic technology can convert better than 30% of the available thermal energy to electrical power and achieves power densities in the ballpark of a kilowatt per 100 square cm (i.e. a disk about 4 1/2 inches in diameter). That's a reasonably respectable carnot engine. This makes it very useful for things like topping cycles in steam plants: You run it with the flame against the hot side so it is at the combustion temperature, and the "cold" side at the temperature of the superheated steam for your steam cycle. Rather than wasting the energy of that temperature drop (as you would with a pure steam cycle) you collect about a third of it as electricity.

It also beats the efficiency of currently available solar cell technology (and the 33.4% Shockleyâ"Queisser theoretical limit for single-junction cells), if you don't mind mounting it on a sun-tracker. Not only that, but you can capture the "waste heat" at a useful temperature without substantial impairment to the electrical generation or heat collection, and thus use the same surface area for both generation and solar heating. (Doing this with semiconductor solar cells doesn't work well, because they become far less efficient when running a couple tens of degrees above room temparature.)

User Journal

Journal Journal: Astute Article on the Turkey/Russia Kerfuffle

A Necessary Conversation

The clash between the Turkish Air Force and Russia is dangerous because it violates the first rule of proxy warfare which is principals don't fight principals. The whole point of proxy warfare is that only the seconds are allowed to cross swords. The duelists are forbidden from engaging each other directly, a convention intended to limit the scope of war.

Comment Re:W.C. Fields Does Politics (Score 1) 7

The whole Bill Cosby takedown should be instructive. When Gloria Allred and a phalanx of bimbos arrive with 88 miles of innuendo, the resulting reality show will make Charlie Sheen look like Billy Graham.
(Was I all over the map there, or what?)

Comment Re:yes (Score 1) 547

oh you haven't heard about the systemd Transfunctional Desktop (STD) ? Your existing apps merely need some changes now to use the mandatory STD API or they won't run, and once modified can't run anywhere else like lesser OS or lesser distros (defined as territory not having any Poettering piss on it)

Comment Re: Private companies don't do exploration of fron (Score 1) 284

The thing is, you're not going to mine 500 lbs of platinum, it's quite possible you're going to mine millions of pounds of it, along with other valuable metals. Yes, you wouldn't be able to dump that on the market too fast, but you would put all the existing platinum mines out of business quickly. And with lower prices for platinum, more uses would be found for it, increasing the demand. More people would want it for jewelry and aesthetics probably, but also it's quite likely new industrial uses would be found for it which were previously unexplored due to its extremely high cost. You have to think more long-term about these things, which it doesn't look like you're doing with your analysis. An endeavor like this isn't going to be something small, it's going to be absolutely huge, and mining a single asteroid will span for decades most likely.

Finally, look at the environmental aspect: mining is terrible ecologically. Wouldn't it be better to do as much mining in space as we can, so we aren't digging giant holes in the ground, polluting groundwater and rivers, shearing the tops off mountains, etc.? We just had a bad incident with river pollution in one of the western states (CO I think), and mining always has problems with environmental opposition in advanced nations (and in backwards nations causes all kinds of problems, like fueling conflicts as with coltan). Environmentalists won't care if you break up asteroids for mineral resources.

Comment Re:Cost of access is key. (Score 1) 284

"Number of people times the years they stay equals the amount of food you need. Etc. p.p."

The amount of calories is probably well established, 2200 KCal/day per person give or take. But how do you design a fully self-contained environment which can provided the needed calories to support a (hopefully) growing population? How much would you need in terms of materials and energy to make such a system work?

Hotels are tired of getting ripped off. I checked into a hotel and they had towels from my house. -- Mark Guido