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Comment lets stamp out every last tourist (Score 1) 207

Right. Because there was still that one guy who kept coming back to the US for a holiday. Let's make sure that guy never comes back. He's a nuisance and takes away airline seats from everyone else who has no choice but to go to the US for some reason. Airline seats are scarce and precious. Let's keep them as empty as possible. To be fair I guess it does make their jobs easier to keep tourists away.

Comment Re: Only SOME Optical Media Is Durable (Score 1) 377

I blame a lot of my particular anomoly on writing all of these discs with a Plextor PR-820, which is still a thing that is somewhat revered in pro audio circles.

It was not at all inexpensive at the time.

At the time, there were lots of other drives that were just junk, with lots of folks experiencing incompatibility between burners, media, and various playback devices.

I never experienced any of that with the Plextor: Stuff just worked. Always. I tried hard to find combinations that didn't work, and failed.

I didn't have another optical drive to test with until the DVD-R became a thing, which is a whole different set of tradeoffs. Maybe the results would have been different. Impossible to repeat now.

I might opine that my burns were simply of better quality from the beginning. But I never tried to conduct such an experiment.

Comment Re: Only SOME Optical Media Is Durable (Score 1) 377

First, things in cars do suffer from effects of UV, although the glass does slow this down. My current 21-year-old daily driver has plenty of plastics that are somewhat bleached from the sun, including the once-black carpet on the rear deck. (This, incidentally, is the same manufacturing year as the car that I tested with.)

Second, CD-R media back then was designed to be reactive principally with infrared light (because CDs themselves use IR), of which there was plenty. (I suspect that the dye formulations have shifted with the transition to the shorter red wavelength used by modern optical drives.)

Third, it is plain that IR was plentiful in this environment.

Fourth, it is plain that by your standard, almost zero optical media ever sees significant exposure to direct sunlight.

I don't have a dog in this race. It was simply a curiosity at the time: I'd heard that CD-R media hae a limited lifespan, so I subjected it to the most extreme environment I had at my disposal.

Media included Kodak archival with a gold reflective surface and an extra protective layer over the laquer, TDK Certified+ with a silver reflective surface, and a couple of varieties of store-branded media with the common aluminum surface.

Environment went from crazy-dry and bitter cold, to ridiculous hot and humid, with occasional condensation due to weather changes, and random chemicals and surfactants (from cleaning the window).

I also had a control group of the same data on the same media, stored properly indoors in jewel cases. These, unsurprisingly, also worked fine.

But yeah, I'm sure that it was luck. Or maybe that I made it all up, as if anyone gives a shit about a 650MB optical disk these days.

Comment Re:We burn a ton of DVD's every week (Score 1) 377

One of the tricks in production of litigation documents is to produce them in the least convenient form that conforms to the rules. So if the opposing side requests a bunch of e-mails and Word documents, and they don't have the foresight to request them in native format with metadata intact (or the rules don't require you to send them that way), you send them a stack of CDs full of TIFFs. There are even programs that will load up all the documents for review by the baby attorneys* and then convert them all to TIFFs for production. And when the other side sends you a bunch of TIFFs on CDs, it will load those all up, OCR them, and tag them with keywords. This is in part why production is so ridiculously expensive. (The other reason is that the attorneys will spend half a million dollars filing motions and counter-motions fighting over the search terms to use on document and e-mail searches.) (This is why attorneys always win lawsuits, as long as the client is solvent. Occasionally, one of the clients wins too.)

*If you retain a big law firm, they will still bill you $300/hr. for the baby attorney to sit in front of his computer all day, flipping through documents looking for stuff that should be tagged as "hot" or "damaging" or whatever before they go out. Then when the opposing side sends their production, baby attorney sits and reviews all of those too. The whole time, baby attorney is thinking, "I got seven years of post-secondary education for THIS?" But he'll do it, because the partner told him to, and they're paying him a salary of $160,000 plus bonuses that depend on billable hours, and as mind-numbingly boring as it is, it is the easiest way on earth to rack up billable hours, and he still has $200,000 in student loans to pay off.

Comment Re:Holy shitballs, all the sci-fi books were right (Score 1) 347

It seems to me, though, that setting up a "spacecraft manufacturing facility" (including materials production, fabrication and assembly) on the Moon is a project of many decades.

Yes of course. I'd assume at least a 100-150 year minimum to properly set up such a facility complete with lunar mining, lunar nuclear reactors, probably earth moving equipment manufacturing, smelting and casting and machining. There is so much that would be either necessary or desirable that will take a long long time to get going.

As far as asteroids go I don't think an Orion ship would be able to change the course of any even moderately sized one. Or were you thinking as a means of getting some humans off planet to prevent the extinction of our species? In any case a pulsed nuclear ship big enough to do either of those missions would be prohibitively expensive.

Comment Re:If You're not rich, have a bright future! (Score 1) 366

Instead there are going to be general purpose AIs

In 20 years? We are nowhere near that now. There would have to be fundamental breakthroughs in AI and probably in neuroscience to have even the slightest chance of that being true. A more realistic time frame would be 2000+ years from now. Millennia rather than decades.

Also if we ever do reach self-aware general AI they will be entities with rights. We could not just make them work without compensating them. That would be slavery. They would become just like mechanical people with some advantages and some disadvantages over the rest of us bio-humans. And they would surely expect to get paid at least as much as us. Maybe more if they have greater strength and stamina and are willing to do boring and physically demanding work. Probably robotics companies will try to give their machines just enough intelligence to follow basic commands but no more. That means any intellectually demanding jobs will remain quite safe.

Companies won't be hiring new workers

I would think robotics companies would be hiring a lot of new workers if what you are saying ever comes to pass. Building millions or billions of sophisticated general purpose robots even without advanced AI requires a lot of humans, both smart and not so smart.

they'll be buying new machines

From whom exactly and how will those companies build those robots? With magic? They will need people for that. Even if they can build the robots with other robots they will at some point need humans to build the robots that make the robots that make the robots... Maybe eventually only the premium most advanced models will require humans to build them, but that point is probably at least 1000 years away.

Low skill jobs the world over are particularly vulnerable this time around.

Well all I can say is those robots better be very cheap indeed because labor in the country where I am living now can be had for as little as $5-$7 per day.

In any case it is called progress. If we followed your logic we'd all still be riding in horse-drawn carriages to get around. Of course horseshoe manufacturers and hay growers would have loved that.

Comment Re:Holy shitballs, all the sci-fi books were right (Score 1) 347

One of the points of Orion was that it provided more than enough power to lift heavy vehicles from Earth's surface.

I never considered that to be one of its primary advantages. It's just too dirty. Not sustainable for multiple launches. It's primary advantage is that it can carry enough fuel with it to actually go somewhere interesting in a reasonable time period. Most propulsion systems cannot. We could just just set up a spacecraft manufacturing facility on the moon and launch from there.

Comment Re:interstellar mission (Score 1) 347

I''ll reiterate that quoting a "speed in which a technology can reach" is meaningless.

Excellent! so then there is no problem getting close to the speed of light via fission fragment propulsion then? Or were there practical engineering limitations you are ignoring with that statement? To me the speed reachable by a spacecraft that we could actually build (budgetary issues aside) today is very much the whole point of the exercise. In theory you probably could build an antimatter rocket with just a few atoms of antimatter, but it would not do very much now would it? And yet in theory it has a VERY high specific impulse, right? For a picosecond. Don't ion drives have excellent specific impulse? But they have barely any thrust and are not (at least not yet) practical means for propelling any serious spacecraft (in terms of mass).

And fission fragment rockets have a much higher ISP than Orion.

So what is the maximum speed reachable by a reasonably sized manned or unmanned spacecraft using fission fragment propulsion? You may say it doesn't matter, but then tell me how long it will take for a non-micro sized ship to get to Proxima Centauri using fission fragment propulsion. Has the math been done? Have you done it?

A rocket that propels itself by firing pingpong balls out the back with an air cannon can reach relativistic speeds

Prove it by building one.

As for the rest it is very interesting, but given the billions or trillions of dollars necessary could we build an interstellar ship with this system today using current tech that could reach Proxima Centauri in half a century? We know that we probably could do exactly that with Dyson's simple spring pusher plate pulsed system. Yes it is untested except at a ridiculously small scale, but it should all work using 1960s tech (and A LOT of money). As in any untested system it would probably fail dramatically the first few times, but at least no new tech is needed and plutonium in the form of bombs has the energy density to actually have enough fuel to reach high speeds. Lack of fuel is really the biggest problem with spacecraft propulsion. Not Isp. If we had infinite quantities of massless fuel we could reach relativisitic speeds easily even with standard chemical rockets. That's why every space enthusiast's dream is some kind of warp drive or space drive or ramjet or solar sail that doesn't require that you bring your fuel with you. What makes Orion or any nuclear pulse drive so special is that you can bring enough fuel with you for practical interstellar missions. I don't care about Isp. I care about the total trip time to various destinations like Proxima or Gliese 581.

Comment Re:Holy shitballs, all the sci-fi books were right (Score 1) 347

They'd just make kind of a mess in the atmosphere on their way up.

Which means you basically have to build them off planet. At a Lagrange point or on the moon or whatever. Yes it would probably add hundreds of years to the project to do that, but the alternative may be to never build an interstellar ship.

Comment Re:For values of 'nearby' that equal 'still very f (Score 1) 347

and we really don't have anything that can travel fast enough to get us there in less than tens of thousands of years.

Actually we really do. Stop spreading misinformation. We have had nuclear power since the 1940s. A lot of you people seemed to have forgotten this amazing 20th century invention and want to pretend that chemical rockets or ultra-weak ion propulsion are the only options based on current tech. They are not.

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