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  1. Re:Energy Density on Canon's Fuel Cell May Drive Portable Gear · · Score: 1
    No, you have to wind up your camera ;)

    I'm talking about a tiny zap of current running through the camera, sortof like a BBQ igniter (except maybe not as snappy), powering the CCD, flash drive and some digital-paper type viewing screen, that doesn't require a constant charge.

  2. Energy Density on Canon's Fuel Cell May Drive Portable Gear · · Score: 5, Interesting

    A hydrogen cartridge wouldn't have the same energy density as an ethnol cartridge, it would have to be pressurized in a strong container, whereas ethnol can be poured into the camera. Sounds like a bad idea from the get go. When are they going to come out with a camera that is powered by the push of the button? They could put a nuclear fuel cell on the camera, but that doesn't make a very handy camera, IMO. No battery at all, now that would be marvelous.

  3. In the dot-matrix printer days on Snooping Through Walls with Microwaves · · Score: 2, Interesting
    It used to be that the old dot matrix printers used to require heavy shielding, because the solenoids inside the printer head would generate a certain radio "sound" for each letter. A van could sit outside an embassy, focus in on the location of a printer, and reproduce a duplicate.

    The United States used this against the soviets for quite a while.

  4. Re:Pray It's All Cancelled. on NASA Scraps Shuttle And Returns to Rockets · · Score: 1

    I'm all about seeing the interplanetary cruiser. I could care less about some dinky robot taking pictures of jupiter.

  5. Re:what drives this controversy? on Lawmakers Support U.S. Control Of The Internet · · Score: 1
    At least other dictatorships make no pretences about themselves.

    What the fuck is this nonsense? Ever heard of the Iraqi information minister?

    And the USA is responsible for the deaths of thousands of civilians in Iraq, at least several British soldiers due to sheer incompetence

    Awww, cry me a river. My brother died in a car accident due to the incompetence of some truck driver. It happens.

    not to mention the hypocritical bullshit spouted by the leaders of that country.

    What is this hypocritical bullshit you speak of? If you ask me, you're the hypocrite, giving everyone a lesson in horrendous actions while ignoring the horrendous action (or INACTION) of others.

    Plenty of people feel that inaction can be just as bad as agressive action, depending on the situation. It would seem as though you are completely unaware of the current situation, you know, violence in the middle east, terrorism, ruthless dictators, all that. AND, you're an idiot.

  6. Re:what drives this controversy? on Lawmakers Support U.S. Control Of The Internet · · Score: 1
    Killjoe, I think you need to read up on your history, like the man says. You don't know what you're talking about. Japan wasn't anywhere close to surrendering. Even after dropping two bombs, the military dictators still wanted to carry on until there was nothing left of Japan. Look at the Kamikazi pilots, they represent the nationalistic pride of MOST of Japan. If it weren't for an emperor with SOME sense in him, we would have had to kill many, many more. Had we developed and used nuclear weapons on Germany, before D-day, we probably wouldn't have ever had to deal with Japan at all!

    You, like much of America, aren't capable of seeing the bigger picture.

  7. Re:Ofcourse their biased on Microsoft Spinning Against OpenDocument Via Fox News · · Score: 1

    I wasn't saying NPR was playing that, you interpreted my comment wrong. Neither of us had to say anything, the station was completely biased, NPR is biased, it's a whole culture of anti-capitalist types, they own the colleges and many not-for-profit organizations. But if I were to tell you things that I think make NPR biased you would just call it objective reporting. It may be called "All things considered" but the certainly consider some things more than others.

  8. Re:Eh, well, it's a matter of scale on ISS Orbit-Raising Attempt Fails · · Score: 1

    Perhaps we'll soon have more private companies like SpaceX ready at a moments notice with their latest rocket, straight off the production line. Currently they have to wait on major governnment contractors like boeing to launch their rockets, which has meant months and months of delays for them. They eventually built their own launch complex in the middle of the pacific, so that they aren't tied down by the current state of things. I think the politics of space travel are going to change in the next few years, with certainty, because they have a production schedule and they don't disappoint with unnecessary hype, at least they haven't yet.

  9. Re:Magnetic thruster (of plasma).... or Ion Engine on Magnetic Field Thruster Developed · · Score: 1

    What are you talking about with the "nuclear" option? A "nuclear" spacecraft uses electric propulsion systems, which have limited exhaust velocity. A nuclear reactor would also be able to ionize larger quantities of matter at once, thereby increasing the force of the thrusters, but not necessarily the efficiency. The efficiency primarily depends on the amount of electricity coming out of the reactor, which itself uses reactor fuel. I think I explained pretty clearly that given current OR future technology, solar sails will always be faster for interstellar travel. In certain cases the solar sail could be complimented with a small electric propulsion system, but I imagine it will not make a whole lot of sense to do that, the propulsion system would be more valuable for getting around in the destination star system. In regards to optics, I think you are limited by your own ignorance. There are more ways to focus a beam of light than lenses and mirrors. The longer you make a solid state laser, the more accurate it would be. Sure your laser pen may fizzle out over great distances, but the solid state component in that laser is like less than a mm wide. You're putting all your money on these theoretical propulsion systems, but yet you think optics have come as far as they ever will. Powerful optics are the key to communicating with the spacecraft over light-year distances. "Sooner or later, the reactor becomes more effective." Not unless your reactor runs continuously for many years. If you could run an electric propulsion system with 100% efficiency you would still be limited by your onboard propellant. You apparently don't realize how much of a burden this is. "A solar sail can't make course corrections in interstellar space, either. At 600,000 mph chemical thrusters would have to be insanely massive to make a difference, so nuclear is the only option." Yes they can make course corrections by tilting the sail, and there is also room for error when they arrive at the destination. In contrast, a reactionary propulsion system would have to spend valuable fuel to make any correction, the tolerance for error would need to be included in the weight of the spacecraft, as extra fuel. The structure of the universe is perfect for solar sails. If your house had a huge jet of air coming from it that could give you the momentum you need to sail through the air to work every day, and vice versa, I think you would abandon your car. You know, Larry Niven came up with the concept of a "ramdrive" spacecraft, which captures interstellar hydrogen with a giant magnetic trap, and expels that out the back of the spacecraft. I think something like that may have the potential to compete with sailed spacecraft, assuming there is significant quantities of interstellar hydrogen. I hope I've opened your eyes to the potential of these spacecraft.

  10. Re:Magnetic thruster (of plasma).... or Ion Engine on Magnetic Field Thruster Developed · · Score: 1
    IIRC, you get a larger change in energy per nucleon (and therefore energy/fuel mass) from fission reactions than fusion. Fission tends to be a dirty process, but we're talking about not activating the reactor until you're outside the solar system.

    That may be the case right now, but you get a lot more energy from a glass of water than you would get from the same mass of plutonium. Right now the fusion reactors are huge, but that's hot fusion we're talking about. In order for nuclear propulsion to reach the efficiency of solar sails, you would need cold fusion. Nuclear reactors tend to become irradiated, the substances break down, lots of nuclear waste, that will be the biggest problem. Shielding the reactor from humans may be easy with a long structure in between the housing and the reactor, but shielding the reactor from itself is the main problem, especially if you intend it to last an interstellar voyage.

    And you still talk about beaming energy to the craft as a viable power source...You would need constant line of sight to deliver power--meaning you would still have to ship your power source off-planet. Even then, the beam would lose focus before you got very far away, plus tracking issues at large distances would be insurmountable--as the distance increases, errors in alignment become more crucial. For a beam tracking a spacecraft at the heliopause, error of only 1 arcsecond means you've missed the target by something on the order of 100 000 kilometers. If you allow the beam to disperse over some narrow angle to compensate (and this will happen to some extent anyway), you eventually run into the same issues as solar power. I just don't think beamed power is feasible.

    It hardly costs anything to beam light to a spacecraft from earth. You could run 50 gigawatts of lasers for years and you still save a lot more money than if you were to load up a nuclear powered spacecraft. You put a couple of them in the hubble orbit, highly eliptical, or better yet put them in the lagrange points. You put massive solar panels in the lagrange points to collect the light, and beam it toward the spacecraft. Better yet, just mirrors and lenses. The spacecraft would come out of the solar system moving at maximum orbital velocity, the first few years would be in a close orbit around the sun with the sails at 45 degrees to the light rays, it could probably get going, I dunno, 500,000mph(?) with durable sail material. How fast do you think the nuclear rockets would go? They have completely different physics, it doesn't work in their favor. I did some reading, the ions coming out of deep space one were going 60,000 mph. Suppose you made an ion thruster that was 10 times more efficient with the fuel. That's 600,000mph. So, if the spacecraft shot 90% of its mass out the back it would be going about as fast as the solar sail? Even if the ion thrusters were 100 times more efficient I don't think they would be able to beat the 100% propulsion efficiency of the solar sail.

    Honestly I think the only reason for the emphasis on nuclear ion propulsion is for interplanetary missions, like Mars, and just to have a nuclear reactor in space. It would be useful for a lot of things, not interstellar travel though.

  11. Re:Magnetic thruster (of plasma).... or Ion Engine on Magnetic Field Thruster Developed · · Score: 1
    NASA's probes have been using nuclear power for years. Granted, they've been using it for powering electronics, not propulsion. Still, solar electric propulsion has been tested, and you'd expect a small nuclear power source could provide sufficient energy if solar power works. Besides, we're talking about an interstellar mission here--you don't want to pack one or two instruments just to decide decades or centuries later that you need more probes. We're not talking about throwing tin cans at the nearest planet, getting to even the nearest star (other than our sun) would be too prohibitively expensive not to pack as much instrumentation as possible on to one ship.

    You're missing my point. If you load up 10 tons of instruments for the craft, your propulsion system would still be 90-99% of the weight in order to get going as fast as you're thinking, and less than 50% of that is used for the initial boost, still need 50% for a slowdown. Even with a solar/nuclear electric ion propulsion system with such efficiency that you can fire the propellant out the back at half the speed of light. If it were solar sails, the goal would be to have the most lightweight sails possible, perhaps a small propulsion system to compensate for the maximum amount of energy we could beam at the craft for the boost, so that it can slow down when it reaches its destination, and maneuver into orbit.

    I wasn't referring to the nuclear isotope generators. I was referring to advanced nuclear fusion power with the highest energy densities man can come up with, still future talk at this point. Solar sails are not. I think if you want to get somewhere outside of our solar system, anything nuclear is bound to be too heavy for any hopes of a short duration trip. The best it could possibly do is less than 50% the speed of light, probably more like 25% for all practical purposes. Those nuclear power cells put out like 100 watts each or something, very little, they stack 3 or 4 or them on most missions and barely get by. A space based nuclear reactor would probably weigh 100-500 tons.

    It would be interesting to see what combination of solar sail and nuclear/solar ion propulsion works best. I'm no rocket scientist but like I said at this point you would want as little weight as possible, so I think any propulsion system would be primarily for maneuvering.

  12. Re:Magnetic thruster (of plasma).... or Ion Engine on Magnetic Field Thruster Developed · · Score: 1
    I hadn't considered any interstellar slow-down, dark matter you mean?

    The simple fix is to beam more energy at the craft. If you were flying toward a larger star then it might make sense to get as much of a boost as you can on the way there. I'm not a rocket scientist either, but I tend to think of GIANT spacecraft when you are trying to get going really fast using propellant, the solar sails would either have to be GIANT as well in order for it to be worth the effort. When you talk about nuclear rockets you are talking kilotons, a solar sail powered interstellar spacecraft could be 1 or 2 tons.

  13. Re:Magnetic thruster (of plasma).... or Ion Engine on Magnetic Field Thruster Developed · · Score: 1
    The exhaust coming out of the ion engine is nowhere near the speed of light. I don't know what it is, maybe 1/100th the speed of light? Other electric propulsion systems may achieve what you're talking about in the future, right now it takes a while for matter to be accelerated to near the speed of light in those huge toroidal partical accelerators, and the energy required to accelerate matter to that speed is tremendous.

    I think travelling at 1/10th the speed of light is a practical long term goal. Solar sails are still the best option IMO. If you really want to go that fast, you MUST be travelling from one star to another, travelling around in our solar system just doesn't necessitate that kind of speed, let alone acceleration :)

    Improving efficiency should be the short term goal. Less fuel, ability to refuel at the destination, these are good things for now. I think 1G of accelleration would be good too in the long run, then the craft could have an artificial gravity. If you were to accellerate at 1G for 24 hours, you would be going nearly 1.9 million miles per hour (compared to 670 million for the speed of light), that aught to get you anywhere in the solar system in a week or two. Jupiter is 500 million up to a solid billion miles from earth, point to point. I wonder how much fuel and the proportion of fuel it would take if your ship was discharging the fuel at near the speed of light.

  14. Re:My opinion, as "a casual observer". on EU Claims Internet Could Fall Apart Next Month · · Score: 1

    It wouldn't be as useful to disconnect the rogue states as it would be to spy on their transmissions.

  15. Re:You know why I'm not trying it? on What is Ruby on Rails? · · Score: 1
    Started programming in Ruby one day because I had heard hype about it and though "WOW, this is a GREAT language!" Then I went looking for web frameworks that use it, I found rails and the community seemed nice. I originally intended to write my own framework because every single framework I've ever used has disappointed me, but there were things about rails that were like, holy shit, that is great! Integrated DB abstraction layer! A really simple templating system!

    It's the first community project I actually feel the urge to contribute to. But if it's not for you it's not for you. Seriously, if everybody used it because they were supposed to, like Java, it wouldn't be as good. Only the elite ever make it to rails, despite it's simplicity.

  16. Re:Seaside ? on What is Ruby on Rails? · · Score: 1
    I think its mainly because seaside doesn't run outside of its own environment. You need to use the seaside webserver to get the continuations support.

    Rails was designed to be more modular, you can use ActiveRecord if you want a DB abstraction layer, you could use ActionPack for the controllers/views, webrick is the web server and someone added continuation support that works with apache, but it didn't catch on.

    Smalltalk is faster than Ruby, I like that, but I like Ruby syntax better than smalltalk.

    I think seaside needs some business guys to come and point this stuff out, it's like some web developer gone mad and did all the cool stuff he could think of without paying any attention to business interests. The popularity of it suffers as well, if there were people pushing seaside it might catch on faster. It's hard enough to find Rails developers right now, but with all the publicity its getting people will start using it more and more.

    Besides, rails isn't all that much worse than Seaside is it? Why don't you quit being such an idealist. :)

  17. Re:Ofcourse their biased on Microsoft Spinning Against OpenDocument Via Fox News · · Score: 1

    NPR is biased, thats all too often overlooked. I worked with a guy who listened to NPR because he thought it was the only source for unbiased news, I was listening to it with him one day while we worked and I started pointing out all the bias. We got to argueing, and in the background I hear this, art(?) on the same station, after NPR was over, which was just a bunch of Bush quotes re-arranged to make him sound like hitler or something, we dropped the argument on that note.

  18. Conservative bias has a face on Microsoft Spinning Against OpenDocument Via Fox News · · Score: 1

    The conservatives on Fox News are openly opinionated, while the liberal bias I see coming from the New York Times and Dan Rather and these types try to mask it behind a neutral face, or no face at all. I 'll read the Washington Post opinion pieces, which I typically don't agree with, but I wouldn't go to an openly liberal publication for my news because they have a track record of deception.

  19. Re: SpaceX on 20,000 Show up for X-Prize Expo · · Score: 1

    www.spacex.com - not to be confused with the x-prize competition.

  20. It's called the browser on Google & Sun Planning Web Office · · Score: 1

    Browser OS 1.0, a rebuild of firefox that includes a boot loader. Javascript will run all the applications, server storage and all that.

  21. Re:Talking to myself on U.S. Insists On Keeping Control Of Internet · · Score: 1
    This is what you call insightful? What are you a bunch of children?

    I suppose we should stop peddling prescription drugs to the rest of the world also.

  22. Re:Talking to myself on U.S. Insists On Keeping Control Of Internet · · Score: 1
    You obviously don't understand the economic facts. It's expected that housing would be comparable to wages, otherwise nobody would be able to afford a house. Exchange rate is exchange rate, if you moved to those countries your money would still get you just as far when purchasing US goods.

    And as far as pension goes, they are pretty good here in the US, too good if you ask some people.

  23. Re:Talking to myself on U.S. Insists On Keeping Control Of Internet · · Score: 1
    This poster catagorizes himself with Saddam Hussein. Both are parts of the international community, and both hate the United States, thus they have everything in common with each other!

    No seriously, the only possible benefactor is Al Gore and his new radio station, after all he invented the internet.

  24. My response to any air force "kicking our ass" on U.S. Insists On Keeping Control Of Internet · · Score: 1
    Anybody who thinks that any other airforce in the world could kick our ass, I have to laugh at. In fact, I think if the world someday decided they were going to "kick our ass", they would have a hell of a time doing it! The only countries that have kept their command and control up to date with real world practice, taking over other countries and what not, is the United States. Chinese generals had better think twice before they invade Taiwan, they haven't invaded a country in what, 60, 70 years? We would most certainly kick their ass, our navy is bigger and more powerful than the rest of the world combined, and god it's nice that that Europe and Asia are finally building their own GPS system. It's just laughable that anybody thinks they could kick the United States ass at anything, even the eurofighter would prove useless against the combined power of the United States. And nobody takes into account all the money we spend on classified defense projects. I wouldn't be surprised if, in a real air superiority battle weapons in outer space start taking out fighter jets. Seriously, we spend hundreds of billions every year on classified projects.

    To sum up my point, these little joint training exercises are a bunch of paltry nations against the United States with a blindfold, hands tied behind back, and a poisoned daggar in the side (in reference to the final scene in the movie Gladiator).

  25. Re:Programmer efficiency on Tech Geezers vs. Young Bloods · · Score: 1
    The old timers who think they know how everything works without keeping themselves up-to-date on the technology are in for a reality check. The technology they used to know isn't what it used to be. You may still have your same old logic gates, but if they were to go about writing low level code like they used to, it would be painfully obvious how far behind they are.

    I think the main issue though is that there is less need for program efficiency and more need for programmer efficiency. You tell a low-level programmer to write you an email client, a month later you get an amazingly fast client that does amazingly little. Tell your average microsoft .NET programmer to write an email client, he probably plops a little "Email Reader" activex control into his form and gives it a name, done in 5 minutes. Those old time programmers had better be writing device drivers or something where their talents are useful, otherwise that would be an awful waste of resources.