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Apollo 11 Moon Landing Turns 45

tragedy Re:Where were you when the Eagle landed? (211 comments)

From the article you link to:

Before the war, Bush had gone on the record as saying, "I don't understand how a serious scientist or engineer can play around with rockets",[56] but in May 1944, he was forced to travel to London to warn General Dwight Eisenhower of the danger posed by the V-1 and V-2.

So, it looks like he wasn't a fan of rocketry in general, which wasn't really particularly visionary of him in retrospect.

about a week ago
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Apollo 11 Moon Landing Turns 45

tragedy Re:Not going to happen again any time soon (211 comments)

Not only that, but you PRAISE IT? And I'M a "nutbar"????

Considering that you are apparently hallucinating praise that doesn't exist in the GP's post, I'm going to say that you may indeed be a nutbar.

about a week ago
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Dubai's Climate-Controlled Dome City Is a Dystopia Waiting To Happen

tragedy Re:Not about jealousy, but ... (265 comments)

It's not necessarily as bad as you make it out to be. Let's say that you have a hemispherical dome covering 4.3 square miles, which I think is what the summary is trying to say. That's a diameter of 3766 meters and an interior volume of about 14 billion m^3, which is something like 17.15 billion kg of air. It's around 1000 joules per degree celcius for each kilogram. So, if you start with a very nasty 45 degrees celcius and get it down to a comfortable 20 degrees celcius, that's 428 terajoules. Obviously Air conditioning is not perfectly efficient. We'll assume an EER rating of 13 for the air conditioning, which may actually be a bit low for a huge commercial system. That's about 38%, so it would take 1.121 Petajoules. Let's say we're powering by gasoline. There's around 120 megajoules per gallon of gas, which translates to around 24 megajoules of electricity per gallon at 20% efficiency. So, that's around 46.7 million gallons of gasoline. Gas is around $2 a gallon in Dubai, so that's around $93.5 million. That's not very much compared to the initial construction costs of such a structure.
That's just the initial cooling, of course, there's still the matter of keeping it cool afterwards. With such a large structure, heat transfer from the outside is almost negligible with proper design. It's a huge number compared to a regular home, but it's very small relative the the massive volume. Then there's the heat generated inside. A typical human puts out around 100 watts of heat just by being alive, then there's all the lighting, cooking, and every other use of power. Guessing a kilowatt of heat generated per person wouldn't be too far off. From the numbers I've found, I'm estimating that they're expecting an upper limit of about 4 million people continuously (180 million visitors per year, guessing they will stay for a week, plus some permanent residents), so that's 4 gigawatts of cooling, or 126 petajoules per year. Going by our previous figures, that's around $10.5 billion dollars per year. That seems like a huge sum of money, but that's only $58 per visitor if they have 180 million per year (and it obviously scales down somewhat if they have fewer visitors).
These numbers are all rough, of course, and use naive assumptions about the shape of the dome, energy consumption, design efficiency, source of power etc. Obviously powering by gasoline would be crazy from an ecological standpoint, but there's an abundance of solar power available there, and the gasoline cost is just a stand-in. The numbers I gave are skewed towards the worst-case scenario, and they're still reasonable. There's nothing impossible going on there. There may be plenty that can go wrong with such a project, but making out the air conditioning in to a near-apocalyptic problem is a bit hyperbolic.

about three weeks ago
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Ancient Bird With Largest Wingspan Yet Discovered

tragedy Re:the length of a 10-passenger limousine (55 comments)

It all depends on exactly which definition of "dinosaur" you use. Many, if not most, modern palaeontologists consider birds to be dinosaurs. Even if you use the traditional definition of dinosaur that restricts them to the Mesozoic, there were birds during the Jurassic and Cretaceous, so you would be saying that birds who didn't survive the era were dinosaurs, but those that did aren't. Which would make it weird for any bird species that survived unchanged well past the extinction. Would that single species be a dinosaur species up to the end of the Mesozoic, but cease to be right at the boundary? Would they just retroactively not be dinosaurs?

about three weeks ago
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Ancient Bird With Largest Wingspan Yet Discovered

tragedy Re:the length of a 10-passenger limousine (55 comments)

That's not really just an idea from xkcd. Modern taxonomists group birds within the clade Dinosauria. Also, birds have tails, even if they're short. The tomia of a number of birds are also very toothlike. A number of dinosaurs, such as T. Rex had all kinds of adaptations to make their skulls lighter relative to their bodies.

about three weeks ago
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IeSF Wants International Game Tournaments Segregated By Sex [Updated]

tragedy Re:simple fix (221 comments)

Faster physical motions will not give you an advantage in chess. I'd say that's not a sport.

So chess is not a sport, but speed chess is?

about three weeks ago
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Court Releases DOJ Memo Justifying Drone Strike On US Citizen

tragedy Re:Yeah sure (371 comments)

He's saying that a byproduct of these people who are deemed (by you)

Deemed by me?

Go bad and read it--unless you're just trolling.

I went back and read the (score:-1 Troll) post again. It still says:

When this happens and there aren't enough people serving their country, they enacts this thing called a draft in which you are forced to join the army and if you do poorly, you end up being fodder for the people more likely to survive to find cover behind while they kick ass.

Sorry still sounds like it's deriding the "fodder" (I'm going to assume that he doesn't actually mean for them to be eaten) and glorifying the cowards hiding behind them.

However should you take some time to produce examples, give the context, explain it, reference sources, argue details, etc. then you may even produce convincement for those noble savages to hold-off on aiding the MIC with their sensibilities of duty and patriotism, and more importantly strength of body, to instead turn such principles towards the demand that the MIC actually serve the ideal of nation which endears them to patriotism.

You really seem to attributing to me a lot of things I didn't actually say. I makes it hard to even understand what you're talking about.

about a month ago
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Court Releases DOJ Memo Justifying Drone Strike On US Citizen

tragedy Re:Yeah sure (371 comments)

You seem to be all for the utter and total betrayal of the "beta" soldiers, for the betterment of the "alpha" soldiers. There doesn't seem to be much else to say.

about a month ago
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Court Releases DOJ Memo Justifying Drone Strike On US Citizen

tragedy Re:Yeah sure (371 comments)

When this happens and there aren't enough people serving their country, they enacts this thing called a draft in which you are forced to join the army and if you do poorly, you end up being fodder for the people more likely to survive to find cover behind while they kick ass.

I'm trying to understand this... Are you glorifying cowards who use other people as human shields? Maybe I'm misunderstanding.

about a month ago
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The Revolutionary American Weapons of War That Never Happened

tragedy Re:Canada's could have been interceptor (133 comments)

The Arrow was fast.. in a straight line.. that's it. Canadians like to crow about the Arrow, and how the US helped to shut the project down, and how all the Canadian engineers helped put the US on the moon. Bull.. Fucking.. Shit. The Arrow benefitted from a shit ton of UK engineers who immigrated to Canada.

If you're going to complain about immigrants working on advanced aerospace technology and the Apollo project in essentially the same breath, it might be worth noting all of the German immigrants who worked on the Apollo project.

about a month ago
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US Marshals Accidentally Reveal Potential Bidders For Gov't-Seized Bitcoin

tragedy Re:Spoils of war. (101 comments)

Good point. That would almost be reasonable, if the proceeds weren't going to the police doing the seizing. If the system were set up so that the proceeds went, for example, into paying back social security, or to pay for services or toys or whatever for orphans... For that matter, if there were just some laws preventing police officers from profiting directly from seized property (no more bonuses to officers, no more first pick of auctioned property, etc.), the situation might be improved. The fact is, found, unclaimed and unowned property shouldn't belong to the police, collectively or individually. If anyone, it should belong to the public. The entire history of laws allowing bounty and spoils for public officials is nothing but a history of corruption. From firefighters burning down houses to judges sentencing innocent people to death for witchcraft. This sort of thing shows that, whatever illusions we may have of living in a more civilized age, we really don't.

about a month ago
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The EPA Carbon Plan: Coal Loses, But Who Wins?

tragedy Re:For fuck's sake, how does this get a 5, Insight (268 comments)

The problem with this is that coal plants can't operate this way.

We've had weather prediction down well enough for the last century or so to be able to handle that kind of lead time. The bigger problem is the cost of maintaining a coal plant for such infrequent use.

about a month ago
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The EPA Carbon Plan: Coal Loses, But Who Wins?

tragedy Re:No winners economically (268 comments)

Australia exports hundreds upon hundreds of tonnes of Coal to China and other countries.

So... a few tens of thousands of dollars worth? Hardly seems worth worrying about one way or another if that's actually the case. :)

about a month ago
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US Marshals Accidentally Reveal Potential Bidders For Gov't-Seized Bitcoin

tragedy Spoils of war. (101 comments)

Am I the only one who gets disturbed every time it's blithely mentioned that this or that police agency gets to take spoils for themselves? It seems a little... inherently corrupt.

about a month ago
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2 US Senators Propose 12-Cent Gas Tax Increase

tragedy Re:Good! (619 comments)

Can you explain to me why anyone ever "buys" a house somewhere with a homeowners association? Seriously, what were you thinking?

about a month ago
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Help Crowd-FOIA Stingray Usage Across America

tragedy Re:The eventual redefinition of "privacy" and the (89 comments)

I know a lot of people whom like to put on their tinfoil hats and cry about government surveillance at every chance, but the reality is that we have never actually defined what is or isn't private in the digital age.

Might be that we haven't defined if phone calls are private in the digital age because they were legally affirmed as private way back in the analog age. Re-reading your post, I'm not sure you understand what the stingray is for.

about a month and a half ago
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A Scientist Is Growing Asparagus In Meteorites To Prepare Us For Space Farming

tragedy Re:Small Question (59 comments)

this is completely wrong.

This is completely wrong.

First, as GuB-42 pointed out, luminous efficiency is an anthrocentric measurement. The numbers on the wikipedia page you referenced where white LEDs go to 22% efficiency at 150 lm/W, and are listed as the most efficient. Obviously, since a white LED is just a blue LED with a phosphor coating to re-emit in different colors, a white LED can't actually have higher radiant flux (watt for watt efficiency) than the blue LED it's made from, or we've just discovered perpetual motion. Also, I should point out that there are LEDs with luminous efficiency (a confusing term) up to 173 lm/W, which is higher than anything on that chart. I should also point out that I didn't specifically say LEDS, so singling out LEDS when low pressure sodium lamps list on that chart with a luminous efficiency of 29% isn't entirely reasonable.

In any case, the numbers I listed were clearly a lot better than those of the original poster, which were off by more than an order of magnitude or three orders of magnitude, depending on which version you look at. This is back of an envelope stuff, not a detailed engineering study. For example, I didn't see you blasting the efficiency number of 15% given for solar cells when the solar cells typically used in space hardware these days are usually in the mid-twenties or above, in terms of efficiency.

you speak with authority on something you clearly no nothing about.

Yeah, I clearly "no" so much less about it than you and bow down in your presence. Really, the fact is that even engineers who deal with this stuff all day long have a hard time keeping up with all the funny little ways to think about light. There's a lot of comparing apples to oranges. I wrote my post because the poster I was replying to was off in their calculations by a monumental degree.

about a month and a half ago
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Cybercriminals Ramp Up Activity Ahead of 2014 World Cup

tragedy Re:How to protect yourself EASILY vs. this? (90 comments)

P.S.=> "The premise is, quite simple: Take something designed by nature & reprogram it to make it work FOR the body, rather than against it..." - Dr. Alice Krippen "I AM LEGEND"

Didn't that end up turning nearly everyone in the world into murderous, light-shunning monsters in the movie?

about a month and a half ago
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A Scientist Is Growing Asparagus In Meteorites To Prepare Us For Space Farming

tragedy Re:Small Question (59 comments)

Also most plants don't grow in weightlessness, they can't figure out which way is "up."

Pretty much all of the experiments done on the ISS show the opposite. The plants tested so far don't care about "up". Or, rather, to them "up" is towards the light source and "down" is towards moisture.

artificial light is hopelessly energy inefficient, a solar collector like a bunch of mirrors could directly use the already present high efficiency light from the Sun, instead of the 15% solar to electric, and 0.01%(r something like that) electric to light, and then 0.1% light to carbohydrate through photosynthesis. The overal process efficiency then is 0.15x0.01x0.1=.00015, or 0.015%, not very high. This is a big issue.

What are you smoking there exactly? .01% efficiency for electric lighting? You did put in in your calculation as 1%, but even that's ridiculously low. Even the earliest electric arc lights weren't that inefficient. For modern electric lighting, you're looking at more like at least 30% efficiency, if not more. I have no idea why you included the "light to carbohydrate" efficiency in your calculations. I'm assuming it was to compare against "artificial chemical mini-reactors", but you didn't really give any numbers or description of those processes, so it's not exactly a reasonable comparison, especially since you can get a lot more from plants than just simple sugars. Efficiency of generated light is also a bit harder to figure out because grow lights tend to be tuned for maximally efficient photosynthesis and don't "waste" as much energy as natural sunlight. Your .01% (although you put it in your final calculation as 1%) efficiency for photosynthesis is typically more like 3 to 6% for plants with real sunlight and would probably be at least upwards of 5% for "tuned" artificial light. It's theoretically possible with efficient enough solar cells and artificial lights to take sunlight in through solar cells and produce artificial light from the electricity which actually is more effective at growing plants than the original sunlight. It would require higher efficiencies than are likely to ever become available, however. Still solar powered grow lights don't actually fare as terribly against direct sunlight as you make it out. Also when comparing with Earth, don't forget that space stations beyond LEO (or even in LEO with certain orbits) will tend to have greater insolation than Earth.

In any case, the actual efficiency is going to end up being something more like .15x.3= .045 or 4.5% conservatively, but probably higher. At the same stage of the game, the power available to a chemical mini-reactor is going to be .15, or 15%, since it's getting its power from the same solar cells as the greenhouse. So, then it's a question of how efficient the artificial reactor is versus the plant at converting its input power source to final product. This is of course ignoring the fact that an assortment of plants (and fungi, algae, etc.) is an incredibly complex chemical factory that can produce everything a human needs to survive, whereas a chemical reactor that produces simple carbohydrates... produces simple carbohydrates.

about a month and a half ago
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Chicago Robber Caught By Facial Recognition Sentenced To 22 Years

tragedy Re:Fingerprints (143 comments)

Whoops, submitted too soon. I was just going to add about your secret evidence scenario (yes, yes, it's only the provenance of the evidence that's secret, not the evidence itself) that Franz Kafka wrote a lovely little story about just such a court system.

about a month and a half ago

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