Just thought I'd follow up: before you accuse everyone else of being a politically-motivated shill, maybe you should take the log out of your own eye? This is one of the only nuke stories I've ever commented in personally, but your history shows that you've scarcely participated in anything else, at least recently. Seems to me like you make things more political than the people you're arguing with do.
Obviously it's a complicated issue, and to understand it in detail is beyond the scope of this discussion. I don't think it matters, though, because only two things really are pertinent: 1.How much radiation is the submitter likely to encounter? and 2. Could that radiation come anywhere close to causing harm to his family? We don't have to understand every part of a system to make useful decisions involving it - often just looking at the relationship between an input and an output gets us a pretty reasonable approximation. Consider as an analogue how well Newtonian mechanics works, which is a dramatic oversimplification of relativity and quantum.
In this case, we can make a good guess at the input, based on the numbers I provided. Sure, ingesting radioactive material isn't good, but do we have any reason whatsoever to expect that to happen? People are far more likely to ingest radioactive material from coal-based fly ash than they are from any overtly nuclear source. You can insert possible calamities all you want, but if we're not going to be realistic about the likely influences on the topic, then this isn't a rational or productive conversation. Assuming reasonable (and even worst case) numbers for the exposure makes it clear that there is little or no meaningful health risk.
In terms of Colorado, once again, I think the simplification is usefully enlightening. Twice or three times the radiation of other states, yet it consistently ranks among the highest in the US for health. If radiation is so dangerous (in small amounts like Tokyo and Colorado experience), we should be seeing a marked impact on cancer in those places. We don't have to think about uranium concentrations or decay times before we can say anything meaningful - we can just look at the fact that increased radiation at these low levels has such a small impact that it is more than overshadowed by the people that are living healthy.
I haven't ever said that you were being too rude to converse with - you must have me confused with another poster. Although, it seems to me that painting your opponent as a shill for some ambiguous pro-nuclear conspiracy is a technique that you're willing to pull when you can't produce numbers to support your argument.
At this point, I think my sources (as scant as they are) speak for themselves. I've shown that Tokyo-level radiation isn't generally harmful - either to civilians or to workers that are directly involved with nuclear every day. Show me otherwise with numerical studies and I'll revise my opinion, but I don't think you'll have much luck doing that because frankly the data doesn't exist.
I don't have anything to gain from people being more level-headed about radiation, except for the intangible benefits of living in a world slightly less governed by fear, and perhaps getting cheaper electricity and cleaner air. I'm just advocating for the idea that we should base our advice and opinions on data, and data shows that low levels of radiation are essentially harmless.
From what I can tell, this is spot on. Don't focus just on grades, the school, and having a double major under your belt - work on extracurricular stuff, a lot of universities have undergrad research programs that would really improve a resume.
University of Colorado at Boulder is the big aerospace school in my area, and they put motivated undergrads to work on various sounding rocket projects and even some orbital experiments. Getting involved with something like that will give you the contacts and experience to have a leg up vs everybody else graduating with you.
Read the article (I know, I must be new here) and one of the parents has a pretty good rebuttal to this kind of thinking: computers are dead easy to learn anymore. It isn't a benefit to anyone if a student can learn to use an iPad - an illiterate 3 year old can do that. I messed around with computers in elementary school, and the only things I remember are Apple LOGO, MS Paint, and a whole lot of Oregon Trail. None of which were useful to me. Learning Word, Excel, and the like is scarcely better - I didn't learn any of those well until I had to use them for college or a job. Most of our tech education, in its current form, is a waste of time.
There are a handful of areas that work well. Teaching programming, research skills, typing, and computer usage in a way that involves some actual challenge and rigor would make a huge difference. Trying to sex up normal lessons with computers, or acting like any time on a computer is giving kids "21st Century Skills" is shortsighted and likely to backfire.
On Tokyo radiation being a non-issue: http://xkcd.com/radiation/
Some excerpts - the extra dose of radiation to Tokyo following the Fukushima incident was only 40 microSieverts, which is about a tenth of the amount of radiation you absorb every year from the potassium naturally occurring in your own body. It is such a small dose that an increase in cancer risk isn't even detectable. Even if you were in Fukushima for 2 entire weeks surrounding the tsunami, you only would've absorbed 1 milliSievert, which is 1% of the dose that shows a perceptible increase in cancer risk.
Conclusion - worst case scenario, the submitter would have nothing to worry about. The doses he could possibly encounter are far below the kind of radiation that could produce any kind of perceptible effect on his or his family's health. Colorado experiences higher radiation than most places because of naturally occurring uranium in the soil and higher cosmic ray incidence (from altitude), yet it is the healthiest state in the US. Eating McDonald's on a semi-regular basis is a bigger health threat than living near a nuclear power plant.
Technology is one of those cases where everybody assumes more is better, without really thinking about where it makes sense and where it doesn't. Now, I don't know that this school's results are all that impressive, especially considering the selection bias that comes with being an expensive private school. But, I have seen lots of money spent on technology at schools, and seen that technology used in a pointless or counterproductive way.
As with most things, I suspect the answer isn't yes or no, but that in some situations it is appropriate and useful and in others it isn't. And, we need the discretion of skilled educators to make that call.
A chest X-ray is 20 microsieverts of radiation. 100 a year would be 2000 microsieverts, or 2 millisieverts. The limit for radiation workers is 50 millisieverts/year, and to actually produce a detectably increased risk of cancer is 100 millisieverts/year.
So, you are right - you could get 100 chest x-rays a year, and you would be at 4% of the allowed limit for a radiation worker, or 2% of the amount that has actually shown any kind of appreciable impact on cancer risk. You'd have a good chance of never experiencing any noticeable side effects because of it. Not saying you should, but you are right that you could.
I never said that the danger from radiation doesn't exist - just that it is overblown. Thanks for proving my point.
I believe the term you are looking for is "echo chamber." Yes, EVERYWHERE ELSE is fear-mongering. Slashdot . . . lead the way to eternal enlightenment
Of course, let us completely ignore the possibility of a nonprofit organization taking measurements for FREE, as it supports your argument. And yes, some guy called "werepants" saying everything is okay is superior than just measuring the area so that you know there is no risk, for sure. . . .
And yes, finally, you are patronizing people for being scared of "invisible" radiation but at the same time telling them they are wasting their time trying to measure it. If anything, shouldn't you support more people trying to measure radiation in their areas so that it is no longer "invisible" and scary? Your political bias is self defeating . ..
Forgive my hyperbole, but literally every mainstream news outlet I frequent (even relatively unbiased ones like BBC) sensationalizes the danger of nuclear radiation. I've only rarely encountered pro-nuclear sentiment, online or off.
I'm not depending on my own authority on this topic, because I'm certainly not a nuclear safety expert (although I've taken a course from one). Anything I've said is 100% provable by looking at the actual numbers. If you are interested, say the word, and I'll provide them. Science isn't about who we should listen to, it is about what the data says, and the data says that this guy has nothing to fear. There are a million more dangerous things that are more of a threat than radiation - a mouse infestation could carry hostavirus, which can infect people through the air and kill a person in a matter of days - there was a pregnant woman who swept her garage, inhaled particles of mouse droppings, and died days later. It isn't a threat that the submitter should lose sleep over, but in many ways it is a worse one than nuclear radiation because it probably shares a similar or higher likelihood and has worse consequences.
Fear is a terrible manipulative influence that our biological cognition is poorly equipped to defend against. We get scared of hugely unlikely things like radiation poisoning, but ignore real and present threats like car accidents. It is important to fight this, because it can cause us to make costly and inappropriate decisions. I don't see it as politics to share factual, verifiable information.
While unlike you I can not say confidently I know how radiation actually works. I am not sure I would even if I had a phd in Nuclear Physics however
I know enough to treat something I cannot touch,hear,taste or smell with a healthy dose of fear.
The problem is that we shouldn't fear something just because it is unknown. It is fair to treat it with caution or healthy respect, but this attitude of fear is really destructive. Humans in general are terrible at assessing risk because we are biologically inclined to be more averse to certain kinds of danger than others. Hostavirus, for instance, is an infection that can kill young, healthy people within days, even with treatment, but there isn't an easy answer for how to avoid it completely or any big industry to rally against. Looking at the numbers for nuclear radiation though, it quickly becomes clear that it isn't a significant danger to hardly anyone. However, since it is associated vaguely with atomic bombs and has a clear industry to rail against, it is easier for people to get on board the hate train.
Don't instinctively fear things that you don't understand. That's a terrible outlook on the world. Seek to learn first, and then make an assessment.
Cool demo, but I think it would be tough to use this as a detector - getting the right alcohol mixture isn't easy, and moving it around while keeping it cold enough would be a challenge. Plus, it isn't even going to give you any kind of quantitative value that you could use to figure out whether or not you have a problem.
yes you are right this "background" radiation does occur naturally and no your are wrong their is reason to fear as their is no known safe level of radiation.
This so called "natural" radiation is thought to be the causes of some cancers.
Not sure if troll or just an idiot.
Colorado, for instance, has a much higher level of radiation than most other states in the US, because it is at higher altitude (less protected by the atmosphere) and, more importantly, there is quite a bit of naturally occurring uranium in the ground here. Yet, the state has some of the healthiest citizens and longest lifespans in the country. The effect of background radiation on health is much less significant than the effect of exercise or a healthy diet or genetics.
So please, before you continue spewing this FUD, educate yourself about how radiation actually works.
That is why Slashdot in broken when it comes to anything nuclear related . ..
It isn't broken. Slashdot is one of the few places where you can get rational discussion about nuclear energy - everywhere else is full of misinformation and fear-mongering. The parent is correct - any potential danger from radiation is overblown. Anyone being honest would tell the submitter that spending money on a geiger counter is completely unnecessary from a safety standpoint.
This isn't politics - this is honesty. Nuclear is safer than virtually all other sources of energy, radiation is a limited and manageable threat, and it is cleaner and more cost effective than most alternatives. By any objective measure, we should be pursuing it, but people who don't understand the science get scared because radiation is invisible and scary.
The second problem is a ship going that fast will accrue mass as it gains speed. Even if we handwave away the issue of powering it, you still get to the point where you're flying a black hole. As you make your way through the cosmos you'll be causing all sorts of mayhem in the solar systems you pass.
I'm no pro at relativity (especially the general variety), but I don't think that you can end up with more mass from kinetic energy than the initial rest mass you started with. If you start off with some kind of badass drive that converts mass directly to kinetic energy, then great, you use e=mc^2 to increase your speed at remarkable efficiency. However, to figure out how much mass your kinetic energy is worth, you use the exact same formula, so it ends up the same. You are never going to weigh more than you did when you left, unless you have something dumping energy into your ship.
You do not understand math. One acre of trees consumes ~19000 lbs of carbon in 7 years. That works out to 2700 lbs of carbon, EVERY YEAR. 19000lbs/7yrs = 2700lbs/yr. Also, the Paulonia trees I used as a reference DO regrow every 7 years, and DON'T EVEN HAVE TO BE REPLANTED. They regrow from roots, to the full height figures I quoted.
So, there is a constant, sustainable carbon sequestration of 2700 lbs, per year, per acre. This is doable for several decades with a single planting. 5 minutes of googling would make this painfully clear to anyone, so please do me the favor of taking the time to understand the argument before you bring another objection.
The original paper does not go into detail about the procedures, because it beyond the scope of the paper. You are supposed to go look these things up for yourself, and the person who wrote this paper very clearly didn't.
Ok, to be fair I haven't read either paper. Apparently I overestimate the judgment of people who publish physics papers (on arXiv, anyway).
I think it's fair to assume that the researcher would read the original paper before publishing a reaction to it, and so we can assume that this is something they didn't already cover in their initial analysis.
Relativity is tricky business, though, so it wouldn't be hard to forget to take something into account. Mass distribution between the two sites, for instance, will cause tiny changes in spacetime, which is certainly not a trivial thing to compute. Hopefully this paper and more like it will help us figure out what is really going on, although we probably won't really be able to put the matter to rest until we get some info from the repeat experiment at Fermilab.
sorry, you have a big big big misconception there:
No, the misconception is yours. After you grow the trees, you cut them down and sell them. Wash, rinse, repeat. There are plenty of wood-based buildings that are over 150 years old, so there's no reason to think that the carbon is going to be released right back into the atmosphere. That might happen in a forest where the trees mature and die and decompose, but clearly you wouldn't let that happen.
Plus, if you drop them all in a deep coal mine somewhere and seal it off, I don't see any reason that the CO2 would be released at all. It is in there permanently until we go dig it out again.
Again, this ISN'T about planting forests. This is about systematically growing and harvesting trees, and then either putting them in permanent storage or doing something with them that is similarly long-lasting.
I worked IT in a school district that ran a few of them - 8 or so. Not terribly significant, but the ones there were nice, and XGrid was slick. I have a friend who's working on building a cluster with a bunch of used ones, and so far he's getting pretty good bang for his buck, but that is probably substantially influenced by all the businesses that are dumping them after Apple cancelled the line.
A redesigned Mac Pro that could work horizontally and fit on a drawer with attachable rack ears would be a start.
You mean like the Xserve? They were really slick servers IMO, but apparently Apple didn't think they were worth the time, because they canceled the entire line a year or two ago. The Mac Pro is nice, but I think they really put the nail in the coffin of their enterprise relationships when they killed their servers.
Yeah, but as I said, you miss the point. You can suck perhaps one years CO2 production out of the air with that (over a 7 years growth period) AND you have to make sure that the wood farmed by this is never decomposing.
So, what is with the rest of the CO2 produced the previous 150 years?
No, the figures I included are annual - so, with that amount of trees, our net CO2 contribution every year would be 0.
Like I said, this isn't a complete solution, but it could certainly be part of one. Look at it this way - if we cut our CO2 production dramatically, these trees would be removing CO2 from the atmosphere faster than we put it in, so it would start to decrease. Also, it took 150 years to put that amount of CO2 into the atmosphere, so I don't think it is reasonable to expect a solution that is going to fix it in a year. Finally, if we have that amount of CO2 sequestration going on, decomposition is something that can be dealt with - bury part of the trees to turn into more fossil fuel down the road, etc.
All that said, I'm not convinced that we even need to start removing CO2, but if we do, we need to be pragmatic about how we get it done. Pie in the sky nanotech systems and massive sequestration plants don't really make sense until we've started doing the cheap, foolproof systems first.
It's all good and well to criticize other people's proposals, but let's see a better alternative, or your own numbers. I highly doubt that any other sequestration scheme can compete, especially in terms of cost.
Now the scientist's jobs will be done by machines as well.
In reality, I'm sure that there is only a very small subset of problems that this system will work for, but, there is no reason that we shouldn't put it to work on those posthaste. It will be interesting to see what it can do with an unsolved problem.
I advice you think a bit deeper, and start applying math.
I bet the whole planet (deserts included) is by far not enough to suck out even a quarter of that amount of CO2.
Math, you say?
Fast-growth Paulonia trees mature in 7 years. In this time, they produce 122 board feet of lumber. 110 trees grow per acre. Their density is 17lbs/cubic ft. I found these figures on the internet, and I'll leave the various unit conversions as an exercise to the reader - I get 19,000 lbs/acre/7 years, or 2700lbs/acre/year. Human activity produces about 5.94*10^13 lbs of CO2 annually. So, we'd need to utilize about 3.44*10^7 square miles to soak up that amount of CO2, which works out to ~60% of the Earth's land surface.
This is a very rough order of magnitude estimate, of course, but I think it illustrates the point well enough - planting an acre of fast growing trees will suck out a literal ton of CO2, every year. And, it will be profitable for whoever is doing it, and produce a useful product.
This isn't a be-all, end-all solution, because clearly we can't devote 60% of our land mass to just growing trees. However, if we combined this strategy with aggressive CO2 reduction measures, it could certainly have an impact. What's your alternative? And how are we going to pay for alternatives, like expensive carbon sequestration technology that isn't self supporting?
p.s - I apologize for using inelegant standard measurements, but that is what my sources provided, and so I just stuck with it. The conclusions should be the same either way.
"Fast growth" lumber is what I stipulated. There are trees out there that go from planted to harvestable in 7 years. Trees are largely made out of carbon, so they are literally taking CO2 and turning it into a solid form. Which can then be buried, used to build a house, or whatever you want. We're spending all sorts of money on technology that can take CO2 out of the air when we have a perfectly good solution staring us right in the face.
If you want a rough estimate of how effective it is, figure out about how much a tree weighs, and that is approximately how much carbon you remove from the air every 7 years, per tree. I'd wager it ends up being a lot cheaper and more effective than just about anything else people have come up with, at least in terms of carbon sequestration. Plus, it creates a useful byproduct that can be sold for profit.
Fast growth lumber has nothing to do with biodiversity - it implies that we are planting massive tree farms and harvesting full grown trees every few years. In that scenario, the only trees getting cut down are ones that we have planted ourselves, so there is no net loss of habitat or anything for the environment.
Actually, one of the best things we could do to get rid of a lot of carbon fast would be to start using wood for building everything, and use as much as possible. Fast growth lumber really sucks the CO2 out of the air, so if we ramped up the amount of wood used in our buildings, etc, we would literally start sequestering CO2 in every new home we build.
Of course, "save the trees" greenies that don't understand science don't like that idea, because of course cutting down trees is BAD...
Slashdot Mirror
Just thought I'd follow up: before you accuse everyone else of being a politically-motivated shill, maybe you should take the log out of your own eye? This is one of the only nuke stories I've ever commented in personally, but your history shows that you've scarcely participated in anything else, at least recently. Seems to me like you make things more political than the people you're arguing with do.
Obviously it's a complicated issue, and to understand it in detail is beyond the scope of this discussion. I don't think it matters, though, because only two things really are pertinent: 1.How much radiation is the submitter likely to encounter? and 2. Could that radiation come anywhere close to causing harm to his family? We don't have to understand every part of a system to make useful decisions involving it - often just looking at the relationship between an input and an output gets us a pretty reasonable approximation. Consider as an analogue how well Newtonian mechanics works, which is a dramatic oversimplification of relativity and quantum.
In this case, we can make a good guess at the input, based on the numbers I provided. Sure, ingesting radioactive material isn't good, but do we have any reason whatsoever to expect that to happen? People are far more likely to ingest radioactive material from coal-based fly ash than they are from any overtly nuclear source. You can insert possible calamities all you want, but if we're not going to be realistic about the likely influences on the topic, then this isn't a rational or productive conversation. Assuming reasonable (and even worst case) numbers for the exposure makes it clear that there is little or no meaningful health risk.
In terms of Colorado, once again, I think the simplification is usefully enlightening. Twice or three times the radiation of other states, yet it consistently ranks among the highest in the US for health. If radiation is so dangerous (in small amounts like Tokyo and Colorado experience), we should be seeing a marked impact on cancer in those places. We don't have to think about uranium concentrations or decay times before we can say anything meaningful - we can just look at the fact that increased radiation at these low levels has such a small impact that it is more than overshadowed by the people that are living healthy.
I haven't ever said that you were being too rude to converse with - you must have me confused with another poster. Although, it seems to me that painting your opponent as a shill for some ambiguous pro-nuclear conspiracy is a technique that you're willing to pull when you can't produce numbers to support your argument.
At this point, I think my sources (as scant as they are) speak for themselves. I've shown that Tokyo-level radiation isn't generally harmful - either to civilians or to workers that are directly involved with nuclear every day. Show me otherwise with numerical studies and I'll revise my opinion, but I don't think you'll have much luck doing that because frankly the data doesn't exist.
I don't have anything to gain from people being more level-headed about radiation, except for the intangible benefits of living in a world slightly less governed by fear, and perhaps getting cheaper electricity and cleaner air. I'm just advocating for the idea that we should base our advice and opinions on data, and data shows that low levels of radiation are essentially harmless.
From what I can tell, this is spot on. Don't focus just on grades, the school, and having a double major under your belt - work on extracurricular stuff, a lot of universities have undergrad research programs that would really improve a resume.
University of Colorado at Boulder is the big aerospace school in my area, and they put motivated undergrads to work on various sounding rocket projects and even some orbital experiments. Getting involved with something like that will give you the contacts and experience to have a leg up vs everybody else graduating with you.
Read the article (I know, I must be new here) and one of the parents has a pretty good rebuttal to this kind of thinking: computers are dead easy to learn anymore. It isn't a benefit to anyone if a student can learn to use an iPad - an illiterate 3 year old can do that. I messed around with computers in elementary school, and the only things I remember are Apple LOGO, MS Paint, and a whole lot of Oregon Trail. None of which were useful to me. Learning Word, Excel, and the like is scarcely better - I didn't learn any of those well until I had to use them for college or a job. Most of our tech education, in its current form, is a waste of time.
There are a handful of areas that work well. Teaching programming, research skills, typing, and computer usage in a way that involves some actual challenge and rigor would make a huge difference. Trying to sex up normal lessons with computers, or acting like any time on a computer is giving kids "21st Century Skills" is shortsighted and likely to backfire.
On nuclear being a safer energy source: .04 deaths per TW/h produced - dramatically lower than even hydroelectric, which is the next closest.
http://nextbigfuture.com/2011/03/deaths-per-twh-by-energy-source.html
Summary - nuclear causes
On Tokyo radiation being a non-issue:
http://xkcd.com/radiation/
Some excerpts - the extra dose of radiation to Tokyo following the Fukushima incident was only 40 microSieverts, which is about a tenth of the amount of radiation you absorb every year from the potassium naturally occurring in your own body. It is such a small dose that an increase in cancer risk isn't even detectable. Even if you were in Fukushima for 2 entire weeks surrounding the tsunami, you only would've absorbed 1 milliSievert, which is 1% of the dose that shows a perceptible increase in cancer risk.
Conclusion - worst case scenario, the submitter would have nothing to worry about. The doses he could possibly encounter are far below the kind of radiation that could produce any kind of perceptible effect on his or his family's health. Colorado experiences higher radiation than most places because of naturally occurring uranium in the soil and higher cosmic ray incidence (from altitude), yet it is the healthiest state in the US. Eating McDonald's on a semi-regular basis is a bigger health threat than living near a nuclear power plant.
Technology is one of those cases where everybody assumes more is better, without really thinking about where it makes sense and where it doesn't. Now, I don't know that this school's results are all that impressive, especially considering the selection bias that comes with being an expensive private school. But, I have seen lots of money spent on technology at schools, and seen that technology used in a pointless or counterproductive way.
As with most things, I suspect the answer isn't yes or no, but that in some situations it is appropriate and useful and in others it isn't. And, we need the discretion of skilled educators to make that call.
Everybody could stand 100 chest x-rays a year.
http://xkcd.com/radiation/
A chest X-ray is 20 microsieverts of radiation. 100 a year would be 2000 microsieverts, or 2 millisieverts. The limit for radiation workers is 50 millisieverts/year, and to actually produce a detectably increased risk of cancer is 100 millisieverts/year.
So, you are right - you could get 100 chest x-rays a year, and you would be at 4% of the allowed limit for a radiation worker, or 2% of the amount that has actually shown any kind of appreciable impact on cancer risk. You'd have a good chance of never experiencing any noticeable side effects because of it. Not saying you should, but you are right that you could.
I never said that the danger from radiation doesn't exist - just that it is overblown. Thanks for proving my point.
I believe the term you are looking for is "echo chamber." Yes, EVERYWHERE ELSE is fear-mongering. Slashdot . . . lead the way to eternal enlightenment
.
Of course, let us completely ignore the possibility of a nonprofit organization taking measurements for FREE, as it supports your argument. And yes, some guy called "werepants" saying everything is okay is superior than just measuring the area so that you know there is no risk, for sure. . . .
And yes, finally, you are patronizing people for being scared of "invisible" radiation but at the same time telling them they are wasting their time trying to measure it. If anything, shouldn't you support more people trying to measure radiation in their areas so that it is no longer "invisible" and scary? Your political bias is self defeating . .
Forgive my hyperbole, but literally every mainstream news outlet I frequent (even relatively unbiased ones like BBC) sensationalizes the danger of nuclear radiation. I've only rarely encountered pro-nuclear sentiment, online or off.
I'm not depending on my own authority on this topic, because I'm certainly not a nuclear safety expert (although I've taken a course from one). Anything I've said is 100% provable by looking at the actual numbers. If you are interested, say the word, and I'll provide them. Science isn't about who we should listen to, it is about what the data says, and the data says that this guy has nothing to fear. There are a million more dangerous things that are more of a threat than radiation - a mouse infestation could carry hostavirus, which can infect people through the air and kill a person in a matter of days - there was a pregnant woman who swept her garage, inhaled particles of mouse droppings, and died days later. It isn't a threat that the submitter should lose sleep over, but in many ways it is a worse one than nuclear radiation because it probably shares a similar or higher likelihood and has worse consequences.
Fear is a terrible manipulative influence that our biological cognition is poorly equipped to defend against. We get scared of hugely unlikely things like radiation poisoning, but ignore real and present threats like car accidents. It is important to fight this, because it can cause us to make costly and inappropriate decisions. I don't see it as politics to share factual, verifiable information.
While unlike you I can not say confidently I know how radiation actually works. I am not sure I would even if I had a phd in Nuclear Physics however I know enough to treat something I cannot touch,hear,taste or smell with a healthy dose of fear.
The problem is that we shouldn't fear something just because it is unknown. It is fair to treat it with caution or healthy respect, but this attitude of fear is really destructive. Humans in general are terrible at assessing risk because we are biologically inclined to be more averse to certain kinds of danger than others. Hostavirus, for instance, is an infection that can kill young, healthy people within days, even with treatment, but there isn't an easy answer for how to avoid it completely or any big industry to rally against. Looking at the numbers for nuclear radiation though, it quickly becomes clear that it isn't a significant danger to hardly anyone. However, since it is associated vaguely with atomic bombs and has a clear industry to rail against, it is easier for people to get on board the hate train.
Don't instinctively fear things that you don't understand. That's a terrible outlook on the world. Seek to learn first, and then make an assessment.
Cool demo, but I think it would be tough to use this as a detector - getting the right alcohol mixture isn't easy, and moving it around while keeping it cold enough would be a challenge. Plus, it isn't even going to give you any kind of quantitative value that you could use to figure out whether or not you have a problem.
yes you are right this "background" radiation does occur naturally and no your are wrong their is reason to fear as their is no known safe level of radiation.
This so called "natural" radiation is thought to be the causes of some cancers.
Not sure if troll or just an idiot.
Colorado, for instance, has a much higher level of radiation than most other states in the US, because it is at higher altitude (less protected by the atmosphere) and, more importantly, there is quite a bit of naturally occurring uranium in the ground here. Yet, the state has some of the healthiest citizens and longest lifespans in the country. The effect of background radiation on health is much less significant than the effect of exercise or a healthy diet or genetics.
So please, before you continue spewing this FUD, educate yourself about how radiation actually works.
That is why Slashdot in broken when it comes to anything nuclear related . . .
It isn't broken. Slashdot is one of the few places where you can get rational discussion about nuclear energy - everywhere else is full of misinformation and fear-mongering. The parent is correct - any potential danger from radiation is overblown. Anyone being honest would tell the submitter that spending money on a geiger counter is completely unnecessary from a safety standpoint.
This isn't politics - this is honesty. Nuclear is safer than virtually all other sources of energy, radiation is a limited and manageable threat, and it is cleaner and more cost effective than most alternatives. By any objective measure, we should be pursuing it, but people who don't understand the science get scared because radiation is invisible and scary.
The second problem is a ship going that fast will accrue mass as it gains speed. Even if we handwave away the issue of powering it, you still get to the point where you're flying a black hole. As you make your way through the cosmos you'll be causing all sorts of mayhem in the solar systems you pass.
I'm no pro at relativity (especially the general variety), but I don't think that you can end up with more mass from kinetic energy than the initial rest mass you started with. If you start off with some kind of badass drive that converts mass directly to kinetic energy, then great, you use e=mc^2 to increase your speed at remarkable efficiency. However, to figure out how much mass your kinetic energy is worth, you use the exact same formula, so it ends up the same. You are never going to weigh more than you did when you left, unless you have something dumping energy into your ship.
You do not understand math. One acre of trees consumes ~19000 lbs of carbon in 7 years. That works out to 2700 lbs of carbon, EVERY YEAR. 19000lbs/7yrs = 2700lbs/yr. Also, the Paulonia trees I used as a reference DO regrow every 7 years, and DON'T EVEN HAVE TO BE REPLANTED. They regrow from roots, to the full height figures I quoted.
So, there is a constant, sustainable carbon sequestration of 2700 lbs, per year, per acre. This is doable for several decades with a single planting. 5 minutes of googling would make this painfully clear to anyone, so please do me the favor of taking the time to understand the argument before you bring another objection.
The original paper does not go into detail about the procedures, because it beyond the scope of the paper. You are supposed to go look these things up for yourself, and the person who wrote this paper very clearly didn't.
Ok, to be fair I haven't read either paper. Apparently I overestimate the judgment of people who publish physics papers (on arXiv, anyway).
I think it's fair to assume that the researcher would read the original paper before publishing a reaction to it, and so we can assume that this is something they didn't already cover in their initial analysis.
Relativity is tricky business, though, so it wouldn't be hard to forget to take something into account. Mass distribution between the two sites, for instance, will cause tiny changes in spacetime, which is certainly not a trivial thing to compute. Hopefully this paper and more like it will help us figure out what is really going on, although we probably won't really be able to put the matter to rest until we get some info from the repeat experiment at Fermilab.
sorry, you have a big big big misconception there:
No, the misconception is yours. After you grow the trees, you cut them down and sell them. Wash, rinse, repeat. There are plenty of wood-based buildings that are over 150 years old, so there's no reason to think that the carbon is going to be released right back into the atmosphere. That might happen in a forest where the trees mature and die and decompose, but clearly you wouldn't let that happen.
Plus, if you drop them all in a deep coal mine somewhere and seal it off, I don't see any reason that the CO2 would be released at all. It is in there permanently until we go dig it out again.
Again, this ISN'T about planting forests. This is about systematically growing and harvesting trees, and then either putting them in permanent storage or doing something with them that is similarly long-lasting.
I worked IT in a school district that ran a few of them - 8 or so. Not terribly significant, but the ones there were nice, and XGrid was slick. I have a friend who's working on building a cluster with a bunch of used ones, and so far he's getting pretty good bang for his buck, but that is probably substantially influenced by all the businesses that are dumping them after Apple cancelled the line.
A redesigned Mac Pro that could work horizontally and fit on a drawer with attachable rack ears would be a start.
You mean like the Xserve? They were really slick servers IMO, but apparently Apple didn't think they were worth the time, because they canceled the entire line a year or two ago. The Mac Pro is nice, but I think they really put the nail in the coffin of their enterprise relationships when they killed their servers.
Yeah, but as I said, you miss the point. You can suck perhaps one years CO2 production out of the air with that (over a 7 years growth period) AND you have to make sure that the wood farmed by this is never decomposing.
So, what is with the rest of the CO2 produced the previous 150 years?
No, the figures I included are annual - so, with that amount of trees, our net CO2 contribution every year would be 0.
Like I said, this isn't a complete solution, but it could certainly be part of one. Look at it this way - if we cut our CO2 production dramatically, these trees would be removing CO2 from the atmosphere faster than we put it in, so it would start to decrease. Also, it took 150 years to put that amount of CO2 into the atmosphere, so I don't think it is reasonable to expect a solution that is going to fix it in a year. Finally, if we have that amount of CO2 sequestration going on, decomposition is something that can be dealt with - bury part of the trees to turn into more fossil fuel down the road, etc.
All that said, I'm not convinced that we even need to start removing CO2, but if we do, we need to be pragmatic about how we get it done. Pie in the sky nanotech systems and massive sequestration plants don't really make sense until we've started doing the cheap, foolproof systems first.
It's all good and well to criticize other people's proposals, but let's see a better alternative, or your own numbers. I highly doubt that any other sequestration scheme can compete, especially in terms of cost.
Now the scientist's jobs will be done by machines as well.
In reality, I'm sure that there is only a very small subset of problems that this system will work for, but, there is no reason that we shouldn't put it to work on those posthaste. It will be interesting to see what it can do with an unsolved problem.
I advice you think a bit deeper, and start applying math.
I bet the whole planet (deserts included) is by far not enough to suck out even a quarter of that amount of CO2.
Math, you say?
Fast-growth Paulonia trees mature in 7 years. In this time, they produce 122 board feet of lumber. 110 trees grow per acre. Their density is 17lbs/cubic ft. I found these figures on the internet, and I'll leave the various unit conversions as an exercise to the reader - I get 19,000 lbs/acre/7 years, or 2700lbs/acre/year. Human activity produces about 5.94*10^13 lbs of CO2 annually. So, we'd need to utilize about 3.44*10^7 square miles to soak up that amount of CO2, which works out to ~60% of the Earth's land surface.
This is a very rough order of magnitude estimate, of course, but I think it illustrates the point well enough - planting an acre of fast growing trees will suck out a literal ton of CO2, every year. And, it will be profitable for whoever is doing it, and produce a useful product.
This isn't a be-all, end-all solution, because clearly we can't devote 60% of our land mass to just growing trees. However, if we combined this strategy with aggressive CO2 reduction measures, it could certainly have an impact. What's your alternative? And how are we going to pay for alternatives, like expensive carbon sequestration technology that isn't self supporting?
p.s - I apologize for using inelegant standard measurements, but that is what my sources provided, and so I just stuck with it. The conclusions should be the same either way.
"Fast growth" lumber is what I stipulated. There are trees out there that go from planted to harvestable in 7 years. Trees are largely made out of carbon, so they are literally taking CO2 and turning it into a solid form. Which can then be buried, used to build a house, or whatever you want. We're spending all sorts of money on technology that can take CO2 out of the air when we have a perfectly good solution staring us right in the face.
If you want a rough estimate of how effective it is, figure out about how much a tree weighs, and that is approximately how much carbon you remove from the air every 7 years, per tree. I'd wager it ends up being a lot cheaper and more effective than just about anything else people have come up with, at least in terms of carbon sequestration. Plus, it creates a useful byproduct that can be sold for profit.
Fast growth lumber has nothing to do with biodiversity - it implies that we are planting massive tree farms and harvesting full grown trees every few years. In that scenario, the only trees getting cut down are ones that we have planted ourselves, so there is no net loss of habitat or anything for the environment.
Actually, one of the best things we could do to get rid of a lot of carbon fast would be to start using wood for building everything, and use as much as possible. Fast growth lumber really sucks the CO2 out of the air, so if we ramped up the amount of wood used in our buildings, etc, we would literally start sequestering CO2 in every new home we build. Of course, "save the trees" greenies that don't understand science don't like that idea, because of course cutting down trees is BAD...