Curious , why not send spent nuclear rods to the sun ?

Discussion in 'General Science & Technology' started by river, Jan 10, 2014.

  1. andy1033 Truth Seeker Valued Senior Member

    Messages:
    1,060
    Thats the answer there.

    How do you know what may happen? Op is making a big assumption about how things work.
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Stryder Keeper of "good" ideas. Valued Senior Member

    Messages:
    13,105
    Considering the cost to send anything into space it's not necessarily the danger that stops such an idea taking place.

    One thing to consider though is our planet is a near Closed system which means any materials you expel out would slowly decrease the materials left here. It would make more sense to look at attempt to reuse the materials or even inject it into our planets core (Although it would have to be looked at very carefully)
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Fraggle Rocker Staff Member

    Messages:
    24,690
    We'll probably have to do this eventually. If we continue to use nuclear powerplants to generate our energy, the waste will pile up.

    Eventually some sensible people will start to worry about our descendants. Suppose there's a catastrophe (meteor, climate, even war might still be possible thousands of years from now) that sets civilization back to the Bronze Age or even the Neolithic Era? They won't be able to read the signs around our dumps, "Danger, radioactivity," and in any case they'll have no idea what the word means. A large earthquake or asteroid might even crack the surface and let radiation leak out.

    Hopefully the time will come when humanity agrees that nuclear power is not something we can keep doing forever. Perhaps by then some technology we haven't even imagined will be available--something based on a science we haven't discovered yet. But if not, the best and safest way to power civilization is by collecting solar energy.

    Build giant solar collection satellites in very high orbit, convert it to microwave frequency and send it down in focused beams to receivers on the surface. This is quite feasible; the math and physics were worked out 40 years ago. You can graze cattle on the land surrounding the receivers, although you probably wouldn't let your children play there.

    The only problem with this scenario is that it would be the largest project ever undertaken by man. It would require the financial support and the manpower of the entire human race, and it would take much longer than a single lifetime to complete it. If world politics is anything like it is today, there's not a chance that we could actually pull it off.

    But perhaps we can build individual satellites one at a time, slowly weaning ourselves off of nuclear power, and eventually they'll all be online.

    I can just see the lobbyists for the nuclear power industry lobbying Congress day and night! Our species is not very future-focused. The fate of people who might be living here 20,000 years from now doesn't concern us.

    If it did, we would not be poisoning the oceans!
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. billvon Valued Senior Member

    Messages:
    21,646
    Don't think that's a very big deal. We recently accidentally dug through the core of a huge nuclear reactor that was billions of years old. No catastrophes. The worst thing that happened was "better avoid that site for a while."

    Let's look at the worst accident in nuclear history - Chernobyl. There is a huge unpopulated area around the former reactor now - and it's the healthiest ecosystem in the country. Not due to the radioactivity, but due to the fact that there are no people there. So if there is an accident that sets us back to the Neolithic Era, and people go back to hunting, we won't care much that 100 years ago there was a nuclear accident there. Mutation rates will be slightly higher, but compared to the #1 source of nuclear radiation that kills people and animals (the sun) it won't even be a blip.


    If we were concerned about our kid's lives, we'd be going nuclear in a big way - and thus avoiding the worst of climate change.

    Agreed there. But the power source that is poisoning the oceans right now is coal, not nuclear.
     
  8. billvon Valued Senior Member

    Messages:
    21,646
    Because it would take more energy to send a kg of nuclear waste into the sun than you get out of a kg of nuclear fuel.
     
  9. Captain Kremmen All aboard, me Hearties! Valued Senior Member

    Messages:
    12,738
    Last edited: Jan 10, 2014
  10. Janus58 Valued Senior Member

    Messages:
    2,397
    For one, temperature doe not equate to energy. The corona has a high temp, but is very very thin, which means that it has very little energy. The entire corona only puts out 1/1,000,000 the energy of the surface of the Sun. For another, do you know what you get when you vaporize a radioactive element? A radioactive vapor. It is very likely that the fuel rods could vaporize by passing this close to the Sun (Just from the intense solar radiation), but this does not change its radioactivity. Again, if it does not hit the Sun, it will return back out to space and stay it orbit around the Sun.
    If the package hits the Sun it doesn't really matter where it does. But, unless you want to waste even more energy, no it won't. While the minimum energy orbit is aimed at the far side of the Sun. It takes almost a third of a year for the package to get there, in that time the Earth travels 1/3 of the way around the Sun, so the impact, from the Earth perspective at that time takes place ~60 degrees from the spot directly pointing at the Earth on the visible side of the Sun.
    It's still too dangerous and it is wasteful of resources.

    Even at the reduced energy cost of kicking it out of the Solar system, you are talking about a fuel to payload ratio of better than 100 to one on the conservative side. ( and a good portion of that payload isn't even the nuclear fuel, it the rocket needed to boost the fuel up to the required speed.
     
  11. Janus58 Valued Senior Member

    Messages:
    2,397
    It's many times worse than that. The cost quoted was for just getting it into orbit around the Earth. You need ~40% more speed to escape the Earth's pull and then multiply that total by some 2.7 times to drop it into the Sun.
     
  12. Russ_Watters Not a Trump supporter... Valued Senior Member

    Messages:
    5,051
    Because it would be expensive and a waste of a valuable resource.
    Clearly, you don't know what the term "vaporize" means.

    Please Register or Log in to view the hidden image!

     
  13. Russ_Watters Not a Trump supporter... Valued Senior Member

    Messages:
    5,051
    [deleted]
     
    Last edited: Jan 10, 2014
  14. Russ_Watters Not a Trump supporter... Valued Senior Member

    Messages:
    5,051
    If we get hit by a meteor hard enough to knock our descendants back to the Neolithic Era, the radioactive waste we left them will be way, way down on their list of worries. That's the primary fallacy behind the Yucca mountain project: considering that today we no consolidated storage system at all, a 100 year storage facility would be a huge upgrade and a 1,000,000 year storage facility is just pointless.
     
  15. Janus58 Valued Senior Member

    Messages:
    2,397
    Because then it could detonate, sending the Moon, along with moonbase Alpha flying out into space!

    Please Register or Log in to view the hidden image!

     
  16. Asguard Kiss my dark side Valued Senior Member

    Messages:
    23,049
    Actually thats been thought of, that is why the signs on long term radiation storage are different from normal HazChem radiation signs

    They use this instead

    Please Register or Log in to view the hidden image!



    This is an interesting artical on the sign
    http://globalnews.ca/news/748374/how-to-communicate-danger-to-future-generations/
     
  17. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    Janus58 told that sending to a distant star would be 6 times cheaper than to the sun. I'll add that slow trip to a star is safer too. If there are physicist there they will know how that mix of then harmless isotopes was made - that they are not alone. But back in late 2005 I told a safer way that would cost at least 100,000 times less:
    phlogistician said: “BAD idea! Saltwater is corrosive, and there is incredible pressure down there. Making a vessel to withstand these conditions would be incredibly difficult, and the results of a breach catastrohpic!...”and I replied in post 21:

    " Wrong. The deepest diving vessels are glass spheres, not steel ones, as glass in compression is stronger than steel, which is more ductile and flows under lesser pressure. Note I am suggesting small SOLID glass disks, not a much larger glass bubble sphere with man inside!

    The disk I described in earlier post will not break etc. at the bottom of the deepest known trench, or even in one ten times deeper, if it existed. In some sense, many rocks 50 miles deep are glass! When the disks are 10 or more miles deep, they probably will have, like rocks at that depth, had some "plastic flow" but still be well defined "inclusions" in newly forming rocks.

    You speak of "vessel." - Perhaps you have not read my original post? (Glass disks I suggest are about an inch or two thick and approximately a foot in diameter with a thin outer layer of isotope-free pure glass that stops the alpha particles. (This only for ease of handling as the range in water of alpha particles is about a millimeter or less.)

    These disk will soon be buried in sea floor sediment and in 10,000 years or so be deeper by tectonic plate movements. It is true that salt water is corrosive. Probably in 100,000 years most of the outer pure-glass layer will have dissolved. So what?

    Even if 10,000 glass disks ENTIRELY dissolved in the first week, that would make an almost undetectable increase in ocean water radiation from natural isotopes already dissolved in sea water!

    Note also that most of the mineral water sold in bottles has more radioactivity per liter than this would add to the ocean. In Brazil the radioactive content of mineral water must be disclosed on the label. The one I drank a few minutes ago had 5.7 “maches” in each liter, but I have no idea how “maches” relates to the units I do know. If you drink “mineral water“, you too drink radioactive water. "

    BTW, pre-WWII the radio activity in water was considered a benefit - a health index. In many places there are caves with natural radioactivity, the rich could afford to sit in while reading a book or hearing music. Some in Hungary were famous health resorts other Europeans came to for health vacations. Hungary has one of the largest lake in western Europe -The largest in central Europe (I've swum in it with some German topless tourist girls* - it is still a resort.)- Nothing better than a swim in it alternating with an hour in the nearby, cool, health-cave out of the sunlight.
    *Working on their suntans in warmer Hungry near one of these cities. First year Hungry was part of EuroRail. Back then my German was not bad, but not fluent.

    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!

    Lake Balaton
     
    Last edited by a moderator: Jan 11, 2014
  18. exchemist Valued Senior Member

    Messages:
    12,545
    You ought to listen to the astronomer, since he will actually know what he is talking about.

    He's saying the cost of decelerating the rocket so that it could hit the sun would be prohibitive. No amount of "positive" or "negative" thinking will alter that. And the safety risk cannot be eliminated, that should be obvious. Rockets (and even manned space vehicles) continue to fail quite frequently, compared to other modes of transport.

    But, knowing what you are like, I don't suppose you will take a blind bit of notice of these reasons. You seem just to want to prolong arguments for the hell of it.
     
  19. river

    Messages:
    17,307
    Why would you decelerate the rocket ?
     
  20. billvon Valued Senior Member

    Messages:
    21,646
    Because otherwise it won't hit the Sun.
     
  21. river

    Messages:
    17,307
    So your saying that a trajectory of a rocket could not be made that the gravity of the sun , on the side of the sun away from us , would not draw this rocket in ?

    I find that hard to believe
     
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    Then you must not understand how momentum (angular momentum especially in this case) is changed. Just sitting in front of your TV you have huge angular momentum about the sun. To nearly zero it* requires large torque acting thru very large distance. That is huge work is required. 6 times more than to lift you up away from the sun's gravitational pull all the way to Pluto and probably more than to just take you out to Mars' distance from the sun and slow you down to Mars' orbital speed, but I'm too lazy to check that guess.

    The safer way to get rid of nuclear waste is described in post 34, a partial repeat on my 8+ year old post. Not only much safer than putting the waste on a rocket, but safer than what is currently being done with it.

    BTW, did I mention the method I suggested long ago is at least 100,000 times cheaper than the "sent it into space solution" and less expensive that the current cost? **

    * So the sun's gravity could, as you suggest, just "draw the rocket in." But BTW, that is not the least energy way to send it to the sun. Giving it a highly elliptical orbit with perigee inside the solar corona is so there is "atmospheric drag" to let sun capture it is the least energy way.

    ** By a factor of at least 5 in life-cycle cost. Perhaps by factor of a 100, if you don't want to have higher cancer rates for any future population.
     
  23. river

    Messages:
    17,307
    So are you saying that we could not compensate for the torque ?

    We can send satellites , space craft , the shuttle , etc. But could not send a rocket to the sun , on the opposite side of the sun which we don't see !!

    Again I find this hard to believe
     

Share This Page