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Comment Re:Actually, the question **I** would like to know (Score 1) 80

A -453F reading, unless you went to great cryogenic pains, means your temperature gauge is either broken or being used under conditions where it doesn't work. The atmosphere never gets below about -130F, and by the time it gets that cold, it's so thin that it has very little impact on the temperature of big solid objects. At that point, objects interact thermally with the outside world entirely by radiation, which is a very slow way to reach low temperatures. Not to mention the flight was in sunlight and had a warm Earth occupying almost a hemisphere of the view, which would keep things nice and warm.

Comment Re:How much computation you ask? (Score 4, Interesting) 43

So what are the implications for reactor design, physicists?

Probably not much. There's so much empirical data about the behavior of fission in reactor-like conditions that, even without a deep understanding of why things happen that way, we pretty much know what happens. That's almost certainly why they simulated the reaction they did -- we have tons of data about it already, so you can tell if the model's good.

Some slight refinements might show up eventually, but the impact of a model like this on reactors will be small.

Most nuclear physicists aren't researching fission reactors, though. The ones pushing the boundaries of the field, coaxing colliders into producing heavier nuclei, investigating weird excited states, and such, are the ones who will really notice this.

Comment Re:"Industrial design student" (Score 1) 167

Option 1 would be consistent with much of my previous experience, if you change out "morons who also don't know" for "enthusiastically naive people who don't pause to consider." "Design" projects emphasize concepts and pretty pictures over execution, cost effectiveness, and practicality, and many of the most severely hyped ideas from that community run the gamut of unworkability from "merely completely impractical" to "would need to reverse basic physics."

Comment "Industrial design student" (Score 5, Informative) 167

Apparently the industrial design curriculum doesn't cover thermodynamics. Condensing water at room temperature requires shedding about 680 watt-hours of energy per liter, and thermoelectric coolers tend to burn off more than twice the energy they pump (depends on a few variables, but practical devices in practical situations usually fall in that ballpark). You'd need somewhere near a constant half-kilowatt to provide for one person's normal water consumption. Much more if they're exercising or in a hot environment.

Comment A thousand dollars? What the hell. (Score 1) 48

If you blow a grand on flying just a camera and tracker, you're doing something amazingly wrong. I worked on a university project that didn't cost that much, and we flew two expensive radios, a SPOT tracker, APRS tracker, Arduino Due flight computer, HD video camera, two GPS receivers, an active thermal control system, and a Kerbal, and we went into it not really knowing what the hell we were doing.

With one flight's worth of experience under my belt, I could put together a decent tracked payload with sensors and a camera for under $200, using off-the-shelf components. Less if I want to spend time making a circuit board. I'm not sure what helium costs these days, but that and a small envelope sure as hell aren't going to add $800 to the bill.

Comment Re:An EMP from a super solar flare... (Score 1) 151

Are you saying that writer doesn't know what he's talking about?

That is exactly the case. There is an infinitesimal kernel of truth at the center of that pearl of idiocy; a high-altitude nuclear detonation does produce geomagnetic field disturbances similar to, but much more violent than, a CME impact. But the effects one normally thinks of as coming from a nuclear EMP -- small electronics being suddenly destroyed by radio-frequency electromagnetic fields -- are absolutely absent from a CME-induced geomagnetic storm.

Comment Re:Backup My Data (Score 2) 151

Or, y'know, be underneath a nice, thick atmosphere. You're absurdly exaggerating the penetrating capability of solar protons. The ones in the CME that will hit on Friday aren't even very energetic, and the MeV scale protons are already here and starting to fade out after a thoroughly unremarkable S1 radiation storm.

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