There are some alternative methods to get things out of the Earth's gravity well besides the space elevator that don't rely on the creation of unobtanium.
There's the idea of laser launch - instead of providing the energy to vapourize propellant with chemical reactions, you aim a laser at the spacecraft to do the job.
Secondly, there's a variety of space tether schemes that don't go all the way down to the surface; instead, they dip down to an altitude and relative velocity where they could be met by hypersonic rockets. These have the rather large advantage of not requiring super-nanotubes. here is a NASA-funded study on the idea.
And, of course, there's always Project Orion - explode nuclear bombs beneath a gargantuan steel plate to push the thing along...but somehow I don't see that one getting approved any time soon:)
This makes more sense than equipping every airliner in the US with anti-missile countermeasures, but not much.
I don't have an exact figure, but there are roughly 500 airports with commercial flights into and out of them in the United States. Some of them only have a couple of scheduled flights a day. At, say, $25 million a pop, it will cost $12.5 billion dollars to equip all those airports with such a system, plus operating costs (presumably you have to have at least one guy babysitting the thing).
And you pretty much have to install these things everywhere an airliner flies. Terrorists aren't stupid (well, actually the evidence is that most of them are, but that's another story. Assuming they're stupid isn't a good idea IMO). They'll realise that if these systems exist, they should pick somewhere that's unlikely to be equipped with it. So while the planes at LAX and La Guardia land and take off with laser-guarded safety, our friendly local terrorists cruise on down to Bum's Rush, Iowa, and take potshots at the one RJ that lands there every day.
But assume these things *do* get installed in every airport in the country. What do our terrorists do? They scrap plan A - missiles at airplane takeoff - and go to the equally lethal plan B, a couple of tonnes of explosives under the grandstand at the local high school football game. Or any one of plans C through ZZ. So we've blown 10 billion dollars to achieve very, very little.
This is almost a quintessential example of protecting against a movie plot threat.
North Korea is trying to deter others from attacking it. To deter that, it wants a credible threat that unnacceptable destruction will result from such an attack. Killing a few hundred thousand Koreans, Japanese, or Americans counts as unacceptable destruction. Hence, no attack will occur, and the missiles stay in their storage facilities.
If I read this, and the GPS article in the Wikipedia, it would now be possible to build a Galileo system out of off-the-shelf parts and some moderately clever software. Is this the case, or is there something I'm missing?
You don't need sub-metre accuracy to be lethal with an ICBM tipped with a nuclear warhead. Land a rocket with a nuke within five miles of here, here, or here and you kill tens, probably hundreds of thousands of people.
Or, alternatively, you could just about hit here with a trebuchet from North Korea, and there are 11 million people there.
North Korean nuclear strategy is likely to revolve around killing lots of people, not taking out hardened military targets with precision weapons. For that, accuracy measured in miles will do just fine.
The article mentioned CORBA's problems with dealing with firewalls.
Correct me if I'm way off base here, but it seems like the following happened with regards to ports:
In the beginning, services were allocated to different ports, with HTTP going to port 80.
Sysadmins decided to block everything but port 80.
Stuff needed to be put through the firewall.
Rather than developing procedures to get ports opened, everything but port 80 stayed blocked.
Protocols were designed to use port 80 to get through firewall.
Selective port firewalling became useless because everything uses port 80.
Clearly, blocking ports selectively is not a sufficient security measure, but being able to block services based on the ports they use is a handy tool to have in the armoury. Isn't it? And isn't it one we've thrown away because sysadmins have been to anally retentive?
Don't connect SCADA systems to the internet without a damn good reason. If you must, put in high-grade security.
Terrorists with ANFO are a lot more dangerous, in general.
Don't panic. There are more likely threats.
Mind you, in 2005 people were still doing stupid things when it came to SCADA system security. Using a home computer to control the water supply of a city of 3 million people? Not smart.
GE would have a pretty fair idea how much enrichment services are going for on the commercial market. And they're interested enough to give these guys a substantial upfront payment plus the promise of a pile of royalties down the track if the pilot plant works and they build a commercial-scale enrichment plant. So presumably they think the method Silex has developed has a reasonable chance of enriching uranium cheaper than centrifuge technology.
This might well be vapourware (if you'll pardon the pun), but isn't it also possible that Silex has figured out things that the project you worked on missed back in the 1980s?
Mind you, USEC was an early investor in Silex, but has decided to instead go with centrifuges for their new enrichment plant, so clearly they came to a different conclusion.
You're absolutely right. We don't need to shoot the moon (if you'll pardon the pun) to get a huge improvement on our current space launch systems. If the full-blown space elevator becomes possible later, great. But we don't have to bet our entire spacefaring future on something that is still basic research away from becoming a possibility.
Mumps is considerably worse as an adult than as a kid; notably, there is a chance (if a small one) that it can leave you sterile. Vaccinate your kids...
Consider a thought experiment. Very large batteries and inverters have to be cheaper to buy (per unit output) than small ones, right? So, let's pretend I'm the power company. Rather than having my customers buy batteries to store off-peak power and use it at peak times, I'll get a great big room full of batteries and do it myself.
But, funnily enough, power companies don't do that, for the very simple reason that having hydro turbines and standby gas generators are cheaper than batteries.
Other schemes, like running your washing machine in the middle of the night to smooth out demand, make sense. But at present prices batteries don't.
If I had a dollar for every time I heard this in the Australian political blogosphere, I'd be a rich man. Australia selling uranium to China (sales to India have not yet been approved) doesn't pose any additional proliferation risk, and, by discouraging reprocessing, may actually help reduce wider proliferation risks.
As for passive solar, I'm all in favour, but there are several issues:
it's not enough
There's an enormous existing housing stock that will take many decades to rebuild.
Passive solar makes SFA difference in high-density living. Do you think 2+ billion Chinese and Indians will be living in American-style McMansions, or apartments?
Jevon's paradox. In this case, Americans spend their energy savings on bigger houses, negating the efficiency gains.
As to your objections to nuclear, low-level waste is really a nonissue...the stuff is simply not that dangerous compared to the myriad other waste we dump into landfills or spray into the atmosphere. Compared to the thousands of lung cancers caused by radon annually, LLW is a piffling risk. High-level waste is the problem, if mostly a political one. See how Sweden is dealing with it.
Finally, terrorism. Nuclear plants are a pretty tough target. How well defended is the Maroondah reservoir?
It seems like it would be even harder to obtain than pure plutonium, and it's not clear from public information whether a neptunium-based gun bomb would work.
Hiroshima-style HEU gun bombs are much easier than that; all you need to do is slam two bits of HEU together fast enough to overcome predetonation. You don't need shaped charges, precisely-timed firing sequences, and the like for that.
Get hold of pure plutonium. To do that, you need to either:
buy it from someone (and thus we're back to the HEU problem),
buy or steal some fuel rods and reprocess those (extremely difficult to do without irradiating yourself to a cinder)
set up your own nuclear reactor (a Chernobyl-style RBMK design would probably be good for your purposes, because you'd need neither enriched uranium nor heavy water), run it, and then reprocess the fuel rods
Then you need to come up with a design that will work. You need to shape the detonation so that the plutonium gets compressed into a perfect, superdense sphere. This requires perfectly shaped explosive blocks with very predictable explosive properties, and precisely timed detonations.
You then need to machine the plutonium. Plutonium is difficult stuff to work with, apparently - not to mention that it's a very (though not uniquely) dangerous inhalation risk.
You'll probably also need to conduct some dummy implosion tests; CFD should reduce the difficulty of this, but I'd be surprised if you could get a working plutonium bomb without it. Implosion testing means that you have to have a big (chemical) explosion somewhere.
And, finally, you need to do all of this in secret; you'll have to fool the national government you're working in, as well as all the major intelligence agencies and the NRO's spy satellites).
I think building a plutonium bomb is well beyond the capabilities of terrorist groups.
Correction - it takes some highly enriched uranium, a library card, and an electrician to make a nuclear weapon.
Making HEU is a very difficult task; Zippe-type centrifuges can't be put together in your back shed. More plausibly, they could steal it or buy it on the black market, but even that's going to be very difficult.
WMD's are a bogus category, in my opinion, draw a bogus analogy between nukes, which genuinely can kill tens of thousands of people at a shot without any great operational genius, and chemical and biological weapons, which seem to be very hard to make that lethal, even though theoretically they can be.
Look, Bill Gates has been a ruthless businessman who has squeezed monopoly profits for as long as he can. He has tried to hold on to that monopoly for as long as he can through a variety of tactics, some possibly illegal and some rather unethical. But, frankly, compared to capitalists throughout history he's a pretty benign capitalist predator. His employees have been well paid. His biggest "victims" have been other Fortune 500 companies, and, to a lesser extent, other middle-class and wealthier citizens of first-world nations. His political manipulation has been rather limited (compared to, say, Rupert Murdoch, whose political interference in his newspapers is legendary). And, as his monopoly slowly fritters away into history (it'll take decades, but it'll eventually go), most of the wealth he has accumulated through it is being invested in third-world health.
When you compare that to the historical record of capitalists who brutalized their workers, raped the third world, manipulated governments at a whim, and so on, Bill is a saint.
The reason I suggested putting the hardware in the iPod is that the additional hardware required would be minimal (making it cheaper) and that it might mean you wouldn't need an additional battery.
But, at the very least, if I were Apple I'd very seriously look at bundling noise-cancelling headphones with my next-generation players. Adding a USP and protecting the world's hearing in one swoop doesn't sound like a bad idea to me...
While this is a good idea, there are other technological measures that can be used to make headphones safer - notably, using noise cancelling technology so people don't need to turn their headphones up so loud in the first place.
I suspect the money it'd cost would be paid back by lower treatment costs for hearing loss down the track.
Thank you for your informative comments. A few follow-up questions; if you're able to answer any of them it would be much appreciated:
Is there a good public critique the weaknesses of the CEV plans that details the weaknesses you describe?
Did people in your company put together a better proposal/s?
Any hints as to the broad outlines?
Did it make it outside your company?
If so, why did NASA choose the plan they've adopted? Boeing and Lockheed Martin both have excellent connections in Washington, as I understand it - isn't that what your company pays its lobbyists for?
If I'm not very much mistaken, you sound very much like you work for either Boeing or Lockheed Martin.
If I understand the general critique of the space establishment from the "rich hobbyists" is that you may well have any number of very bright engineers, but your corporate masters make a hell of a lot of money off cost-plus contracts using the same old stuff and have no incentive to actually build anything new and better. Even if somebody like Musk had have come along you wouldn't take his money because the tech that gets developed would ultimately reduce the value of future government work.
Slashdot Mirror
There's the idea of laser launch - instead of providing the energy to vapourize propellant with chemical reactions, you aim a laser at the spacecraft to do the job.
Secondly, there's a variety of space tether schemes that don't go all the way down to the surface; instead, they dip down to an altitude and relative velocity where they could be met by hypersonic rockets. These have the rather large advantage of not requiring super-nanotubes. here is a NASA-funded study on the idea.
And, of course, there's always Project Orion - explode nuclear bombs beneath a gargantuan steel plate to push the thing along...but somehow I don't see that one getting approved any time soon
Do you really think that you'll be able to do it any cheaper than using conventional electricity to run a reverse osmosis plant?
Seeing I've been running it on my AMD64 system for what seems like an eternity... :)
I don't have an exact figure, but there are roughly 500 airports with commercial flights into and out of them in the United States. Some of them only have a couple of scheduled flights a day. At, say, $25 million a pop, it will cost $12.5 billion dollars to equip all those airports with such a system, plus operating costs (presumably you have to have at least one guy babysitting the thing).
And you pretty much have to install these things everywhere an airliner flies. Terrorists aren't stupid (well, actually the evidence is that most of them are, but that's another story. Assuming they're stupid isn't a good idea IMO). They'll realise that if these systems exist, they should pick somewhere that's unlikely to be equipped with it. So while the planes at LAX and La Guardia land and take off with laser-guarded safety, our friendly local terrorists cruise on down to Bum's Rush, Iowa, and take potshots at the one RJ that lands there every day.
But assume these things *do* get installed in every airport in the country. What do our terrorists do? They scrap plan A - missiles at airplane takeoff - and go to the equally lethal plan B, a couple of tonnes of explosives under the grandstand at the local high school football game. Or any one of plans C through ZZ. So we've blown 10 billion dollars to achieve very, very little.
This is almost a quintessential example of protecting against a movie plot threat.
North Korea is trying to deter others from attacking it. To deter that, it wants a credible threat that unnacceptable destruction will result from such an attack. Killing a few hundred thousand Koreans, Japanese, or Americans counts as unacceptable destruction. Hence, no attack will occur, and the missiles stay in their storage facilities.
If I read this, and the GPS article in the Wikipedia, it would now be possible to build a Galileo system out of off-the-shelf parts and some moderately clever software. Is this the case, or is there something I'm missing?
Or, alternatively, you could just about hit here with a trebuchet from North Korea, and there are 11 million people there.
North Korean nuclear strategy is likely to revolve around killing lots of people, not taking out hardened military targets with precision weapons. For that, accuracy measured in miles will do just fine.
Correct me if I'm way off base here, but it seems like the following happened with regards to ports:
Clearly, blocking ports selectively is not a sufficient security measure, but being able to block services based on the ports they use is a handy tool to have in the armoury. Isn't it? And isn't it one we've thrown away because sysadmins have been to anally retentive?
Don't Copy That Floppy :)
Mind you, in 2005 people were still doing stupid things when it came to SCADA system security. Using a home computer to control the water supply of a city of 3 million people? Not smart.
This might well be vapourware (if you'll pardon the pun), but isn't it also possible that Silex has figured out things that the project you worked on missed back in the 1980s?
Mind you, USEC was an early investor in Silex, but has decided to instead go with centrifuges for their new enrichment plant, so clearly they came to a different conclusion.
Brazil just opened a commercial uranium enrichment plant. They can become a weapons state any time they feel like it.
You're absolutely right. We don't need to shoot the moon (if you'll pardon the pun) to get a huge improvement on our current space launch systems. If the full-blown space elevator becomes possible later, great. But we don't have to bet our entire spacefaring future on something that is still basic research away from becoming a possibility.
Mumps is considerably worse as an adult than as a kid; notably, there is a chance (if a small one) that it can leave you sterile. Vaccinate your kids...
But, funnily enough, power companies don't do that, for the very simple reason that having hydro turbines and standby gas generators are cheaper than batteries.
Other schemes, like running your washing machine in the middle of the night to smooth out demand, make sense. But at present prices batteries don't.
As for passive solar, I'm all in favour, but there are several issues:
As to your objections to nuclear, low-level waste is really a nonissue...the stuff is simply not that dangerous compared to the myriad other waste we dump into landfills or spray into the atmosphere. Compared to the thousands of lung cancers caused by radon annually, LLW is a piffling risk. High-level waste is the problem, if mostly a political one. See how Sweden is dealing with it.
Finally, terrorism. Nuclear plants are a pretty tough target. How well defended is the Maroondah reservoir?
It seems like it would be even harder to obtain than pure plutonium, and it's not clear from public information whether a neptunium-based gun bomb would work.
Hiroshima-style HEU gun bombs are much easier than that; all you need to do is slam two bits of HEU together fast enough to overcome predetonation. You don't need shaped charges, precisely-timed firing sequences, and the like for that.
I think building a plutonium bomb is well beyond the capabilities of terrorist groups.
Making HEU is a very difficult task; Zippe-type centrifuges can't be put together in your back shed. More plausibly, they could steal it or buy it on the black market, but even that's going to be very difficult.
WMD's are a bogus category, in my opinion, draw a bogus analogy between nukes, which genuinely can kill tens of thousands of people at a shot without any great operational genius, and chemical and biological weapons, which seem to be very hard to make that lethal, even though theoretically they can be.
When you compare that to the historical record of capitalists who brutalized their workers, raped the third world, manipulated governments at a whim, and so on, Bill is a saint.
But, at the very least, if I were Apple I'd very seriously look at bundling noise-cancelling headphones with my next-generation players. Adding a USP and protecting the world's hearing in one swoop doesn't sound like a bad idea to me...
I suspect the money it'd cost would be paid back by lower treatment costs for hearing loss down the track.
Thank you for your informative comments. A few follow-up questions; if you're able to answer any of them it would be much appreciated:
If I understand the general critique of the space establishment from the "rich hobbyists" is that you may well have any number of very bright engineers, but your corporate masters make a hell of a lot of money off cost-plus contracts using the same old stuff and have no incentive to actually build anything new and better. Even if somebody like Musk had have come along you wouldn't take his money because the tech that gets developed would ultimately reduce the value of future government work.