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Comment Re:Why Now? (Score 1) 175

Well, my point is that specifics matter. I don't think we should issue blanket condemnations of the NSA, nor blanket pats on the back.

What they do is important, but also full of temptations for abuse. They're a lot like police in that respect. The police play a critical role in our society, but that doesn't make them beyond criticism, in fact quite the opposite. People on either "side" (the very notion of "side" is broken) can't seem to grasp the necessity for standards that are both tough AND fair.

Comment Well... (Score 1) 484

A working Hiroshima style fission bomb isn't that hard to build, which is why the Little Boy bomb had that particular design. But getting the 64 kg of fissile materials you need to build one is a bitch. Unlike as depicted in many bad post-apocalyptic novels, you can't produce bomb grade nuclear fuel in a basement or a small cave. It requires massive industrial facilities and leaves evidence which is impossible to hide. That's why non-state actors have never been able to produce a nuclear weapon, despite the fact that such as weapon is highly desirable and some of them are well-funded. And there's getting the uranium in the first place; you need a theoretical minimum of about nine tons of purified but unenriched uranium to start, and in practice quite a bit more if you don't have forever to do it.

For a private actor, obtaining a nuclear weapon is extremely unlikely, barring some breakthrough in physics or chemistry.

Dropping a big space rock, on the other hand, is limited not by physics, as you suggest, but by economics. At present it's economically impossible, but if there were private space activities such as near Earth asteroid mining, everything you'd need to do it would be there, so the only missing piece would be intent. As for using lunar materials, the same applies, it's just farther off because the cost of getting stuff out of the Moon's gravity well means lunar mining is only attractive for materials destined for space use.

And note that even if obtaining a nuclear weapon were considerably easier than it is today, you still couldn't rule out an opportunistic space attack. It could be the guy running the mining scow, or even hacking an automated vehicle's software. That's something well within the capability of a wealthy individual, not to mention state actors.

At some point we're going to have to deal seriously with the space rock attack scenario. But that's decades off. When someone starts a project to move dense masses in space on the order of a metric ton or so, that's the time that governments need to step in with oversight. Right now it's still in the realm of sci fi.

Comment Re:Spin it properly (Score 1) 224

Well, they're supposed to post nutrition information, and you should generally go by that. If the sandwich patty is supposed to be 50% soy, and it say the plain sandwich has so many grams of carbs, that should be that.

However, if the test results don't match what the company expects, some franchisee may be off the reservation.

Comment Re:But radio plays a lot of Jay Z (Score 5, Informative) 191

No, he's saying that corporate programming managers are too timid to take risks.

It's hard to understand what's been lost if don't remember radio from when most radio stations were independently owned, and of course manually operated by an on-site engineer and broadcaster.

Yes in a major city there might be a handful of top-40 "hits" stations, a handful of talk or sports radio stations too, but aside from that almost every station on the dial had an unique and reflected some personal perspective. Often they were labors of love, with owners or DJs promoting genres of music they enjoyed personally, like classical or jazz, or towards the end, hip-hop.

This wasn't a case of being destroyed by a disruptive technology, like newspapers. This was a case of a deliberate rules change which allowed corporations to own a large fraction of radio stations in a market, combined with the ability to automate radio stations across the country so that they are in fact exactly the same no matter where you go, with allowances for slight regional differences like the preponderance of Christian radio across the South.

Comment Re:Horrible...if true (Score 1) 307

The troubling thing in these situations is always the possibility of the sour grapes/personal vendetta scenario you describe. That said, the very doubt this automatically raises means that a prudent person doesn't take such an accusation lightly.

As I say to my kids, with seven billion people on the planet you can find examples of virtually any kind of behavior you can imagine. It doesn't make that behavior normal or representative of anything.

So you can't jump to any conclusions one way or the other. You can try to gauge how credible this person sounds, but what other people might have done has no bearing on that.

Comment Re:Why isn't Uber being sued? (Score 2) 307

Well, I don't know about the amount of evidence adding up to a proverbial shitton, but let's suppose for sake of argument Folwer's accusations are true. It doesn't automatically follow that she'd want to or ought to sue.

On the other hand suppose she is fabricating this story. It doesn't necessarily follow that she'd want to sue either, for obvious reasons.

CONCLUSION: Fowler not suing Uber is not evidence of anything one way or the other, because you can start with either assumption and concoct perfectly plausible explanations for her not wanting to. You have to decide whether you believe her based on other evidence.

Now for the record I find Fowler's accusations credible, because they're consistent (a) with what I've seen in dysfunctional organizations and (b) what I've heard about Uber. That said, that's not really conclusive. But if I were considering employment with Uber, I'd be very, very cautious, even though I'm not a woman. A place that tolerates one kind of mistreatment against one kind of employee isn't a good place to work, even if you're not that kind of employee.

Comment Re: Rockets are too expensive (Score 1) 349

You are confusing two different coordinate systems. Both can be true at the same time -- corkscrews and figure 8 -- but not in the same coordinate system.

Looked at from the outside, in the so-called "Galilean frame", you would see the satellite making corkscrews. Another observer on the surface of the earth would see the satellite tracing a figure 8, in his coordinate system.

Since your two coordinate systems are rotating with respect to each other, the parametric equation of motion looks very different. A fixed point in one necessarily traces some kind of spiral in the other.

Comment Re: Rockets are too expensive (Score 1) 349

I think we were thrown off point by AC, who doesn't seem to grasp that physical systems can be described in alternative reference frames.

I think he is trying to say that there is no such thing as a geostationary orbit, because satellites in that orbit are actually tracing out a circular (or even more pedantically, spiral) path.

I believe the responder was trying to point out, using the example of a rocket ship travelling to geosynchronous orbit, that "stationary" is a kind trick of perspective when viewed from the frame of fixed stars.

Of course in the rotating frame of where we happen to be sitting on the Earth geostationary satellites are indeed actually stationary.

Comment Re: Rockets are too expensive (Score 2) 349

geosynchronous satellites: when the sun circulates over the north pole and it causes the satellite to exhibit the figure 8 orbit

geostationary : are fixed (fiction) stations , allegedly ground based

That is the most garbled explanation I've ever heard of geosynchronous orbits.

A geosynchronous orbit is one with a period that exactly matches the Earth's rate of rotation.

Geostationary orbits are a special case of geosynchronous orbits where the angle inclination of the orbit to the Earth's equator is zero.

So: a satellite in a geosynchronous orbit that is also geostationary appears to continually hover 22,236 miles above some point on the Earth's equator. If it is in a geosynchronous orbit that is not geostationary, it will appear from the earth to drift north and south of the celestial equator, tracing a figure 8 against the background stars over the course of one Earth rotation.

Of course in both cases the satellite would actually be following an elliptical (in fact almost perfectly circular) path around the Earth. The "stationary" or "figure 8" thing is simply a trick of perspective -- the way car in the next lane traveling at the same speed appears not to be moving.

Yeah, most of you knew all that. But insofar as there's an explanation here, it oughtn't be gibberish.

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