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User: MartinSchou

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  1. Re:manned space exploration = fail on Europe's Space Agency Wants To Do What NASA Can't · · Score: 1

    He said he could see the point in a manned mission to Mars. Rather difficult to get to Mars without getting into LEO or higher.

    Since he said nothing about not going to LEO I once again fail to see your point

    He said:

    a manned trip to mars would be the only goal i could think of that would truely be worth the price tag for an achievement just to say

    Now, I'm not a rocket scientist, but you seem to be much more knowledgeable than I in this area. How do you manage to get anything from the surface of Earth to Mars without going faster than the speed needed to attain low earth orbit?

    According to Wikipedia, Earth's escape velocity is 11.186 km/s. I'm pretty sure that's faster than the 7.814 km/s needed to get into low earth orbit. Faster speeds requires more energy, thus making it impossible to get to Mars through space travel without getting into or past low earth orbit. But your ideas intrigue me, and I am very curious to hear in what way I'm making insane assumptions by using LEO energy requirement as a starting block. For one thing it was a simpler thing to look up than the speed you'd need to be at to go for Mars.

  2. Re:manned space exploration = fail on Europe's Space Agency Wants To Do What NASA Can't · · Score: 4, Insightful

    He said nothing, I might note, about manned flights into LEO

    He said he could see the point in a manned mission to Mars. Rather difficult to get to Mars without getting into LEO or higher.

    So what do those manned mission to the moon gain, please do explain.

    What is the point in going to Mars? Or having bases in the Antarctic? Going to the moon is a decent proving ground for a mission to Mars. It's close by - four days travel vs a couple of months at the moment, radio contact has a few seconds delay vs several minutes.

    Just setting foot on Mars and going "well, let's head back" would be stupid. Mostly because you can't really do straight return missions with our current technology. And if all we're sending are unmanned probes, time isn't exactly of the essense, meaning there's no point in trying to develop fasters ways of getting there.

    Setting up a base on Mars isn't going to be easy. We'd need to more or less bombard the planet with supplies before we set foot there ourselves. A lot simpler and faster to test perfecting landing and aiming against the Moon. Same with building a base on the planet. We've tried building various selfsufficient habitats (like Biosphere 2, and they've been mixed successes. Those only tackle some of the issues we'd be facing on Mars, and unless we're 100% certain we can replicate the successfull experiments we will conduct on this here on earth, it'd be silly not to use the Moon as testing grounds. Much cheaper, faster and easier to ship replacement parts to the Moon, when we find that something doesn't work like we thought

    It's also a good place to test how to build a base, that will stop us from dying of cancer. No magnetic field means really nasty things with regards to radiation, and neither Mars nor the Moon has a suitable magnetic field. Probably better to learn somewhere close by rather than months away.

    How about figuring out how to set up production centers from scratch? If we can produce our own raw materials, fabricated materials etc. all the way to custom made production utilities, we can save a ton of money in supplies. We'd still need food, water and fuel, but if we can kick start industrial production planet/lunar side, we're pretty much golden. Hell, if we can manage to build a nuclear reactor, we don't even need that much fuel.

    Now, as for using the Moon as a 'stopping off station' for trips to Mars, I rather doubt there's a point to that. The Moon is about 380,000 km away, Mars is between 55,000,000 and 401,000,000 km. That's between 0.7% and 0.09% of the distance. Essentially the argument seems to be that if we're flying to the other side of the Earth on vaccation, we should really book some hotel time between 18 and 140 km away from our house. I expect it gets even worse if you do the energy equations rather than just distances.

    Now, using the Moon as proving ground for the technology we need to survive on Mars is just common sense. Unless we develop some way of getting to Mars and back that can be done in a few weeks round trip, but I don't think that's something we're going to see any time soon. But then again, my crystal ball IS broken, plus I'm an Aries - we don't believe in that kind of stuff.

    But even if we ignore a possible mission to Mars - what could we get from the Moon? How about the largest and best isolated radio telescope? The best optical telescopes possible - no atmosphere to worry about, much lower gravity which I suspect would allow you to build much much larger mirror arrays. No annoying neighbours who complain that your telescope is blocking their view.

    Imagine building an optical telescope that covers the entire bottom of the Cabeus crater. It isn't subjected to sunlight, it's about 100K making IR astronomy even easier. I'm pretty sure the entire astronomy field can see a point in going to

  3. Re:manned space exploration = fail on Europe's Space Agency Wants To Do What NASA Can't · · Score: 2, Insightful

    how about we solve the cost issue of just getting into orbit

    This is a fairly straight forward problem with no solution apart from possibly mass production. It inevitably takes so much energy to get to orbit - nothing apart from discovering new laws of physics will change that. That doesn't mean there aren't ideas on the drawing board, that will lower the cost by something like a factor of ten - but none of those are suitable for anything you want to stay alive.

    Low earth orbit requires a speed of a minimum of 7,814 m/s. Now my math is a bit rusty, so I might be off by quite a bit. To get to 7,814 m/s you need 30.5 Mjoule/kg. That's ignoring everything else, including drag. And like I said, that number is probably wrong, but let's go with it for a moment.

    Usually we use hydrogen in our rockets, and with an energy density of 10.1 MJ/liter, we'd need 3.02 liters. At 0.07 kg/liter that's 211 grams. At 1 g/mol that's 211 mol of hydrogen, so we need 105.5 mol of oxygen (2H2 + O2 => H2O). At 8 g/mol we need 844 grams of oxygen as well. So, just to get the energy required to get 1 kg of mass up to the speed required for low orbit, we now have to handle 1.055 kg of fuel.

    We also need some way to contain that fuel - more weight.
    We need some way to control the rate at which the fuel is spent - more weight.
    We need some kind of survival system for the human - more weight.
    We need some way to get him back down safely - more weight.
    We need something that keeps him alive while in orbit - more weight.

    So suddenly we don't need to accelerate just 1 kg of mass to 7,814 m/s, we might need to accelerate 4 kg to that speed. This isn't something we can just magic away.

    work on alternative propolsion systems to get places faster

    And how exactly do you propose we do this, without putting stuff into orbit to test if they actually work in real life as well?

    before blowing our cookies over manned trips to the moon, which add NOTHING of scientific value and solve no problems.

    So ... if you're taking your homebuilt duct-tape sail boat out for a test, you'd rather aim for crossing the ocean than checking if you can get somewhere close by? The moon is pretty far away. Apollo 17 took 4 days and 14 hours from launch to lunar landing. But apparently you don't see any value in learning how to get there faster than we can already manage? Oh, wait - you were just complaining about that. My bad.

    As it happens, they ARE working on various solutions to these and many other issues. And while your idea of "scientific value" apparently doesn't stretch to cover such things as developing new types of engines, material science to lower the weight you lift into orbit, developing better and lighter life support systems etc. While you may think those are just engineering challenges, they aren't until you actually have the science behind it nailed down. And even if it's just trial and error, that's still a scientific approach. And strangely enough, much of what we learn in space technology may "only" be engineering and production prowess, but that comes in pretty handy as well, and it can pay pretty good dividends.

    But you're right of course. Much better if all we do is not aim for pie in the sky, but aim for banana cream cake on Mars.

  4. Re:uname on XKCD Deploys Command Line Interface · · Score: 1

    guest@xkcd:/$ whoami
    You are Richard Stallman.

    guest@xkcd:/$ cat
    You're a kitty!

    guest@xkcd:/$ bash
    You bash your head against the wall. It's not very effective.

  5. Re:6x 22"? What about one large TV? on Radeon HD 5870 Eyefinity 6 — Gaming On Six Panels · · Score: 1

    A 1080p monitor is 1920x1080 pixels. That is a 16x9 format (16x120 = 1920 and 9x120 = 1080). It's still 50% too slim to match the 24x9 perspective.

    If it was a 3x3 configuration, it'd be the same format. But it's 'only' 3x2, so you're cutting a third off of the height. If you want to get an idea of the perspective, try setting a game to a resolution of 1920x720.

  6. Re:The real summary on MIT Finds 'Grand Unified Theory of AI' · · Score: 1

    Interesting idea. But that doesn't quite suit the concept of flight.

    Flight is the process by which an object moves either through the air, or movement beyond earth's atmosphere (as in the case of spaceflight), by generating lift, propulsive thrust or aerostatically using buoyancy, or by simple ballistic movement. I know, I know - don't believe Wikipedia. But go on - look it up in your offline dictionary. I'll wait.

    Even if you look up helicopters, you find such interesting things as "first flight", "flight controls" etc. But you're right - it's just moving through the air by generating lift, but it's not flying.

    I am curious - what human contraptions DO fly according to your definition? And by all means - elaborate on how they manage to fly and how that prevents helicopters from doing the same thing. And when you're thinking about that, take into consideration that things like a V-22 Osprey can work exactly like a helicopter.

  7. Re:6x 22"? What about one large TV? on Radeon HD 5870 Eyefinity 6 — Gaming On Six Panels · · Score: 1

    One thing to point out with those videos and the review is that the FOV is like a typical monitor.

    Mmm ... no, it's not the same. Regular wide screen TV: 16x9. Regular wide screen monitor: 16x9 or16x10

    A six monitor (3x2) wide screen setup will be: 48x18 (16x3 and 9x2) or 48x20 (16x3 and 10x2). This is 24x9 or 24x10 which is 50% wider than 16x6 and 16x10 respectively. But thank you for playing.

  8. Re:Interesting tactic, won't work. on Warner Brothers Hiring Undercover Anti-Pirates · · Score: 1

    Region locking?

    When Obama visited the UK, his present to Gordon Brown (Prime Minister) was 25 DVDs with classic American movies.

    Anyone willing to bet that those DVDs are region locked to region 1?

  9. Re:War on Open Source, Open Standards Under Attack In Europe · · Score: 4, Insightful

    I'm sure Alabama feels the same way? They're having dictated social, educational, health, economic etc politics from DC.

    While it is rather difficult to leave the EU, it's not impossible, whereas secession is apparently against the constitution of the US.

  10. Long live the ability to read ... on How Do You Land a Nuke-Powered Mini-Cooper On Mars? · · Score: 1

    It's always fun when you misread titles like this and end up with:

    "How Do Yo Nuke a Land-powered Mini-Cooper On Mars?"

    Not that I have any idea just how a land-powered vehicle would work, but the imagery was intriguing.

  11. Re:To quote the great Bob Saget on Fatty Foods May Cause Cocaine-Like Addiction · · Score: 1

    obody sucks dick for weed, and nobody overdosed on the stuff *ever*...

    Be that as it may, I'm pretty sure we can find some examples of people dying where the immediate cause can be said to be hemp.

  12. Re:Dunno on Battlefield Earth Screenwriter Accepts Razzie · · Score: 1

    "Battlefield Earth" is to a Scientologist like "The Ten Commandments" is to a Christian Fundamentalist

    So fundamentalist in fact, that they've reverted to Judaism. I've never quite understood why so many "Christian fundamentalists" find all their arguments in the Old testament. That's not your book. You have a new - it's called The NEW Testament.

  13. Re:Consenting adults on Could Colorblindness Cure Be Morally Wrong? · · Score: 1

    If I want to put a drug into my body, it's my right.

    I'm sure that'll make an interesting argument if you are arrested for having heroin, cocaine, LSD, ecstasy, magic mushrooms and various other illegal drugs on you. Even if they are only for your own consumption.

    I agree that it should be up to me to decide, what I put into my body, to the extent that it is possible, but legally that just isn't the case.

  14. Re:WTF? Just ask the patient. on Could Colorblindness Cure Be Morally Wrong? · · Score: 1

    Short-sightedness can also be viewed as unique perspective on reality.

    And there are stories of people in Africa who, upon being given their first pair of glasses, were astonished to find out that there were mountains nearby. That's a fairly unique perspective on reality.

  15. Re:Nonsensical ... on It's Time To Split Up NSA Between Spooks and Geeks · · Score: 1

    who can say this new agency won't have spooks in there from the NSA?

    The same reason that you don't have spooks in the FBI and DMV?

  16. Re:The more I see of Obama... on Will ACTA Be Found Unconstitutional? · · Score: 1

    The more I see of Obama, the more I want him impeached.

    Let me guess - you also want him charged with treason?

    Do you have any idea what exactly are required to impeach someone? Or are you just throwing that word around because it has a nice ring to it?

    Also, why only Obama? The ACTA has been in the works since 2006, and I'm pretty sure Obama hasn't had anything to do with it before he took office.

    And why is Obama the only who who needs to speak up on why he wants the ACTA? How about every single federal politician - they do have the power to stop it if they so wish, but I rather doubt they do.

    But I suppose you're right. It's much simpler to just scream at the top of our lungs that we want to see the blood of the scape goat and just ignore all the people who are also backing this ridiculous thing.

  17. Re:Fermi needs a refresh or v2 on Nvidia's GF100 Turns Into GeForce GTX 480 and 470 · · Score: 4, Informative

    In the AnandTech review the GTX400 is 2x-10x faster than the GTX 285 or Radeon 5870.

    That's overstating it WAY too much.

    In certain benchmarks the GTX480 is quite a bit faster than the 5870, but what you're saying is that it is across the board, which is just not true. From the conclusion of the AnandTech review:

    To wrap things up, let's start with the obvious: NVIDIA has reclaimed their crown - they have the fastest single-GPU card. The GTX 480 is between 10 and 15% faster than the Radeon 5870 depending on the resolution, giving it a comfortable lead over AMD's best single-GPU card.

    There is a massive difference between "10 to 15%" and "2x-10x faster".

  18. Re:Be sure to vote with your wallet on Nvidia Drops Support For Its Open Source Driver · · Score: 1

    especially - because you can't change cards in a laptop

    Actually you can, it "just" requires that the laptop uses MXM modules. Granted, MXM modules aren't exactly easy to find, and there aren't that many notebook models using them, but you can in fact swap graphics adapters in laptops.

  19. Re:Microsoft's tax cut and a sales tax on 10% Tax On Custom Software, $100M Tax Cut For Microsoft · · Score: 1

    sales taxes are not just not-progressive - they're regressive.

    I bet Glenn Beck loves sales tax then, because he really hates anything remotely connected to progressive.

  20. Re:Andrew would be upset, again. on 10% Tax On Custom Software, $100M Tax Cut For Microsoft · · Score: 1

    While your ideas are interesting, you seem to forget to think about the long term consequences. Example:

    Fire and Police are local, and should be paid for by local taxes like property taxes, since they are used to protect property.

    Low income municipality, 50,000 inhabitants, 30% unemployment, people living in worn down apartment buildings.

    High income municipality, 10,000 inhabitants, 5% (chosen) unemployment, people living in expensive self-owned houses.

    It is entirely possible that the high income municipality has a tax base that is twice or three times as big as the low income municipality. That means that under your idea, they could have three times as many cops and firemen as the low income area. Fair enough - but do they really need 15 times as many cops and fire fighters per inhabitant as the low income one? Which one is more likely to have violent crime? Which one is more likely to have fires? Which one is more likely to have fires that affect multiple families?

    Same with the proposed road taxes. Let's only use fuel and vehicle (ownership) tax to build and maintain roads. And if the low income workers happen to live far away from their jobs, they now have to pay a lot more to get minimum wage. The local stores will have to pay more for their goods. And then you still end up with badly maintained roads in the low income areas, which in turn leads to increased costs of working and living, as transport to and from those areas become more and more expensive, as the roads get in worse and worse shape.

    If you build society in such a way, that you do not in one way or another distribute wealth around to those who need it, your society will end up suffering. Maybe not in a way that you yourself get to see up front, but think about this - what will happen to the US economy, if the long commutes you already have become infeasible? It's not impossible to imagine a situation, where you'd have to pay 50% of your post tax income just to get to and from work. Moving is expensive.

  21. Re:Tools on Perelman Urged To Accept $1m Prize · · Score: 1

    And just how do you manage to maintain an average speed of 168 km/h (104 mph) in the middle of Boston

  22. Re:Oblig. Good Will Hunting quote on Perelman Urged To Accept $1m Prize · · Score: 1

    Doesn't apply. The lottery ticket Chuckie is talking about isn't cash. It's the ability to get himself out of the boring ass jobs he's stuck in, and that his friends would love to get out of but don't have the ability to leave.

    This guy is in the opposite situation. He used to do what he loved - math. And then the math community fucked him over, repeatedly. And now the same community is asking him to come back. Pretty please. They'll even pay him quite a lot of money. Pretty please with sugar on top.

    Might as well ask Fritzl's if she'd like to make a shit load of money by moving back into that dungeon for a reality tv show.

  23. Re:It's a lose lose on Dell To Leave China For India · · Score: 2, Insightful

    those of the lower castes in India would disagree with you, where many are beaten, murdered, systematically denied legal representation, denied justice by government, given jobs in inhumane working conditions, denied educational opportunity.....

    Give it time. India has been a democracy for 60 (or 63) years.

    63 years into the life of the US (1839) the US also had a lower caste - slaves. Not in all of the US, but the 13th amendment wasn't adopted until 1865 - 89 years into its life. And I'm pretty sure we can find similar bad stories about every western democracy. Just look at women's suffrage. Or have a look at how we treat homeless people or ex convicts.

    But for some reason we in the west seem to believe, that we can just copy the social 'equality' that we have grown into over a long period of time, onto countries that are not only very inexperienced in democracy, but also have a completely different cultural history. That's just not going to work.

  24. Re:HFC on High Fructose Corn Syrup Causes Bigger Weight Gain In Rats · · Score: 1

    Supposed effects on sperm are unnoticed in any human populations or tests.

    I misread that as taste

  25. And how many kids fall victim to this? on Tracking Pedophiles By Their Typing Habits · · Score: 1

    Seriously - how many kids fall victim to this kind of thing?

    And how many kids are molested by their family, family friends and other trusted people they meet in real life.

    How about we just simply abduct all kids from their families at birth and have them be raised by robots until they're 18? It'd definitely save more kids from being molested.