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Comment A better nickname is in order (Score 0) 20

Glad they're running the contest, and congrats to ESA/JAXA... but this really shouldn't be likened to "America's Cup". The America's Cup is a sailing race, between actual sailboats. It's about not just design, but implementation: the vagaries of wind, the ability of sailors to collaborate, the properties of materials, tactics, reacting in real-time, etc.

When I think "America's Cup of rocket science", I'd want, ya know, actual rockets racing against each other. If "rocket science" is going to be to rockets what "computer science" is to computers, there are "games" and "prizes" and "competitions" and even "Olympiads" (which also sounds more like people actually running, but it's at least in wider use). "America's Cup" is very specifically about a racing event, and I think that this really gives the wrong impression. Some day we'll have an "America's cup" for rockets... but today isn't that day.

Comment Re:Goth Perfume? (Score 3) 49

It's also concentration- and context-dependent. Putrescine, for example, is found in a lot of foods (in parts-per-billion quantities). Cheeses include both putrescine and cadaverine; the distinction between "ferment" and "rot" is kind of arbitrary. Without those flavors, the cheese would taste different. The small amounts are not automatically repulsive.

A number of compounds are pleasant in tiny doses and noxious in larger ones. They're not even identifiable as the same; people treat them as entirely different. My favorite example is butyric acid, which smells like vomit in concentration, but like butter when dilute. Another (and I'm afraid the exact molecule is escaping me) smells like either honey or cat urine, and is found in both.

Comment Re:Considering how fast Google ditched China (Score 1) 381

Just because it's "on the internet" doesn't mean that Google is exempt, or that it's suddenly censorship because it offers what was once a paid service for free.

The shift from paid to free does seem to make a difference here. Google is the go-to search engine, but other engines can do reasonably well for very little money. If somebody wants to find you, they can ditch Google and grab a no-name search engine at zero cost to themselves. That's a shift from the days when there were a small number of search companies, who had to put in a lot of money on each search, and thus were easier to regulate and oversee.

It wasn't perfect, but it could be reasonable. Today, it's hard to see how removing yourself from Google really preserves your privacy in a significant way. Web crawlers are just too easy; easy enough to be free.

The way I see it, privacy is not what it used to be, and that's a genie that's not returning to the bottle. I don't know what the final evolution of society will be as it grapples with that. It may well be necessary to go through this experiment, where they try forcing Google to forge and it doesn't help. Or hell, maybe it will help just enough, in the way that crappy luggage locks keep out casual theft while failing to deter anybody really intent on crime.

Comment Re:Been saying this for years (Score 2) 683

And I just don't see the point in spending a lot of money just to ensure that "the human race" survives. Whether it's a few hundred people surviving a nuclear winter, or a few hundred people surviving the perpetual Martian winter, none of those people are likely to be me or anybody I care about. "The Human Race" is just too broad an abstraction to get me to emotionally engage with it.

I'd much rather see that kind of money spent on improving the lives of actual living human beings right now. I'm not opposed to space research or other sciences with only hazy, indirect payoffs. I'd just rather see it done in more cost-effective ways, with robots and telescopes. I wouldn't even mind manned missions, if they seemed feasible. But the idea of establishing a colony just so that "the species" can continue to exist seems pretty hokey to me.

Comment Doing the Math (Score 1) 55

SPOILER ALERT: Spoilers about the first chapter of the book follow! (Because someone is likely to complain about that kind of thing.)

Has anyone actually done the math on this? We are not talking about a man being blown around in a windstorm, really. We are talking about equipment that NASA launched to Mars getting blown around in a windstorm. The ascent vehicle getting blown nearly over is a stretch, for sure, but perhaps the injury that befalls the protagonist is not. It was inflicted on him by a piece of metal that was thrown by the windstorm. I am not qualified to do the math, but I hope someone else here is.

While the protagonist and most likely the ascent vehicle are fairly heavy, presumably everything else that NASA spent rocket fuel to put on the surface of Mars is as light as it can possibly be to still do its job. It would not take much air density to pick up a piece of metal that has high surface area and small mass, like a thin piece of aluminum with a bend in it to make it rigid would be. It certainly could be whipped by the 150kph (42m/s) wind. Anything near that speed and it would not have a problem piercing a spacesuit or damaging a circuit board. Maybe it would not likely have enough energy to do both of those things and still seriously injure a human, but it is at least plausible from this high-level perspective.

So, who here has the knowledge and the energy to run the numbers on whether this is more than just plausible and actually possible? I wish I had the former because I certainly have the latter and enjoyed the book--the plot, the technical details, and the writing style--enough to want other people also to enjoy it. Maybe Randall Munroe will give it a shot, although it is a bit non-absurd for his usual taste.

By the way, let's give the author one deus ex machina point for how he solved the final problem that his characters faced. Does he get a negative deus ex machina point for how he created the first problem that they faced and thus balance it out or do both problems and solutions have positive valence when counting the dei ex machinis?

Comment Re: How is this paid for? (Score 1) 1291

That's why their leaders come to the USA for treatment.

As an American, I don't see how I benefit from a health care system that according to you is good at providing care to the wealthy and powerful of the world, but which we also know is crappy at providing care to the rest of us. Are you suggesting that good health outcomes for select individuals trickle down?

If a health care system that worked better for the vast majority of Americans happened to also discourage the elite from treatment here, I'm prepared to live with that. In no small part this is because under the current system I might not wind up living at all.

Comment Re:If I were king.... (Score 5, Informative) 70

The last time somebody tried this was the Library of Alexandria which required the dictates and commands of several kings. Even then they had to pay money to the Athenians to get some documents.

Well, that was because the Library wanted to make a copy of the original manuscripts of Aeschylus, Sophocles and Euripides. Athens was reluctant to allow the manuscripts to be sent to Alexandria (presumably they would've preferred to have them copied in Athens), but ultimately allowed it provided that the Library provided a cash deposit to ensure the safe return of the manuscripts.

Instead, predictably, the Library kept the originals and returned the copies, and was happy to forfeit the money, which was almost 500 kilograms of silver.

The normal M.O. of the Library was just to require that all documents going through Alexandria be available for copying by the Library, and to be a major port and trading hub so that a lot of documents happened to pass through.

It all worked pretty well (for a library that relied on hand-copying, the printing press not being invented yet) until some assholes burned the place down.

Comment Re:Citation needed (Score 4, Interesting) 191

The idea is that if we don't find anything, the next most likely place to go looking is at the energy where the strong, weak, and electrical forces unify, around 10^13 TeV. The number they give is a few orders of magnitude below that; we probably wouldn't have to get all the way to the grand unification energy to see hints of new particles. I think that's the evidence you're looking for; it's justified by our present theory.

It's a "reasonable assumption" in that those theories begin to break down at that scale. We expect our theories to hold quite well, which would mean that we wouldn't expect to find anything novel until we got close. And then we have every reason to expect to find new things, which is what you need to help drive a theory that's measurably different from our present one.

Of course we never know what we'll find, but it would be hard to build any sort of intermediate-sized collider, which would cost insane amounts of money, and theory predicts that it wouldn't find anything of value unless it were even bigger. It could be even worse; they might not find anything for a few more orders of magnitude, at which point they'd be probing not just the strong, weak, and electrical forces, but also gravity. We know for certain that the theory breaks down there, but the amount of energy required to probe the breakdown is simply ludicrous.

Comment Re:What About Nutrition? (Score 1) 122

I think there's a lot to be said for eating the things that can be grown locally and in season. It's not clear to me if it's actually a direct win for the environment or nutrition, but I think that it pays dividends in the way we think about our food. A lot of people seem to expect asparagus 365 days a year, and it skews their perceptions of how food is made. And that in turns affects the choices we make about the whole system, and especially about what we put into our bodies.

I believe that the root of the obesity problem is that people just don't think about their food. Most diets work for a while, not because you need this special nutrient or avoid that special villain, but because they make people pay attention. When you pay attention to what you eat, you eat fewer of the nutrition-free calories that aren't doing anything but making you fat. When you pay attention, you can find that a 2,000 calorie budget is actually quite a bit of food, when it doesn't come in tiny ultra-dense blocks of fat and sugar.

So it may not really save that much energy, if any, to get lettuce from a local grower. But the fact that you think of that lettuce as something special, something you care about, does a lot psychologically. You eat it instead of a bag of chips and come out ahead.

Comment Re:What About Nutrition? (Score 1) 122

Centralizing agriculture far away and transporting pesticides and fertilizers to that site and then transporting the produce, sometimes half-way across the globe, represents a huge waste of energy, with the pollution that goes along with that.

Well... maybe. I've heard differing analyses on this. It's counterintuitive, but there are economies of scale associated with mass production. Trains are incredibly efficient, and so are the massive container ships: the square-cube law means you're moving more stuff and less vehicle. Local produce carried in the back of a pickup truck can burn as much fuel in 50 miles as a thousand miles in a freighter. There are similar economies of scale on the inputs: dragging fertilizer to a thousand local farms will be less efficient than one tanker full of it.

That's far from the whole story, of course. Local foods can take better advantage of local conditions (including less pesticides), can be better varieties since there's less shipping, are often mixed-use rather than monocultures. I know a local farmer who uses no fuel whatsoever on his farm... though a fair bit of energy is used hauling his produce from the country to the city, around 50 miles.

I do prefer to eat local when I can, but the fuel advantages aren't nearly as overwhelming as it might seem.

Comment Re:As they say (Score 1) 206

Mostly that if it actually did kill a lot of people, the corporation would take a lot of heat for it. The corporations do frequently try to push the limits on that, and the punishment for that isn't nearly severe enough. But they do actually take considerable steps to avoid having it happen accidentally, and it's really not in their best interest to do it deliberately.

The biggest problem is in ground beef. If you add one infected animal to the hopper, you can make millions of pounds of meat dangerous. That's expensive.

Note that I'm not a fan of industrial meat production, and I avoid it. That has more to do with concern for animal welfare during their lives, and with flavor: if an animal is going to die for my dinner I want it to taste less bland than the meat you get at grocery stores and most restaurants. Plus, a few environmental issues. And yeah, safety is a bit of a concern... but they do want to avoid killing people. Bad for business.

Comment Re:Sorry, but Apple still deserves most of the cre (Score 2) 354

Eject a disk by moving it from my desktop to the trash with all the files I want to delete? Makes sense.

Well, to understand this, you have to recall that early Macs had to be able to run off of a single floppy drive. Users might buy a hard drive or a second floppy drive (or if they had a dual-floppy SE, a third floppy drive for some reason) but it couldn't be relied on. Yet they still had to be able to tolerate having the OS disc ejected at times.

So there was a distinction between physically ejecting a disc while keeping it mounted (which was represented onscreen by a greyed out disc icon) so that you could copy to it, and both physically ejecting _and_ dismounting a disc.

The formal way that you were supposed to do this was by using menu commands. The Eject command was for eject-but-keep-mounted while the generally ignored Put Away command was for eject-and-dismount. It was also possible to use Put Away on an already greyed out, ejected-but-mounted disc icon.

User testing showed that this was inconvenient, and one of the OS developers eventually created a shortcut for the Put Away command, which was to drag a disc icon to the trash. It wound up being so popular that it shipped.

Apparently there had been some thought at the time about changing the Trash icon into some sort of Eject icon in the case of ejecting a disc, but apparently this was felt to be confusing or too difficult, so it wasn't done. In OS X the idea was revisited, and now the Trash icon does turn into a standard Eject icon when you're dragging a disc.

In any case, in real life, whatever confusion dragging disc icons to the trash might have caused, everyone got over it basically immediately.

Switching tiled applications makes the one menu bar change? Sure. It's not like moving the cursor half the screen for each click is a waste of time.

It's not; since there's nothing above the menubar, you can just slam the mouse up. It turns out to be faster and easier than having multiple menu bars. The Mac and Lisa groups did consider per-window menubars, but having tested the idea, it was rejected. For example, here's some polaroids of a screen from 1980 showing a Lisa with a menu attached to the bottom of a window: Later that year, the menu had moved to the top of the windows: And early the next year, it finally settled at the top of the screen:

Comment Re:A HUD is usefull... (Score 1) 417

I also can't see why I'd want a built-in satnav, though I wouldn't mind having a cradle that connected my phone to a larger display. The one advantage to builtin satnav is that the display can be clearer and more informative.

I own an add-on Garmin, and while I like it, I use my phone far more often. Among other things, it has a much better understanding of traffic and how to route around it. (My particular Garmin model does get traffic information over the air, but that information is much less precise and useful than the Internet can give it.) I keep it around for those days when I'm out of coverage, and a few other circumstances, but it's mostly relegated to taking up space and getting out of date. (It also has map updates, but they don't happen automatically. And a major new interchange near my house took a very long time to appear. I didn't need it, but people coming to my place sometimes got confused.)

So I can see why a car my want I/O features, but the smarts might as well be relegated to the device I'm already carrying with me. It would be nice to have better audio controls than fiddling with the phone itself, for example.

"I may be synthetic, but I'm not stupid" -- the artificial person, from _Aliens_