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A dumb neutrino question?

  1. Nov 20, 2009 #1
    I just watched the movie 2012. Now I know it's just a movie and a bit of fantasy.

    What I want to know is, is there any type of radiation from the Sun that can penetrate a few miles into the Earth's crust and have some sort of effect on the rock down there. For example, can the amount of radiation in a rock be slowly increased over time only from radiation coming from the Sun? Do neutrinos become trapped in rock a few miles under ground and become detectable?

    Thanks for any answers.
  2. jcsd
  3. Nov 20, 2009 #2


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    neutrinos go through the earth easily
    only a very small percentage of them are stopped by the rock

    they aren't trapped as such - they are absorbed by an atom and have an effect, changing the atom
  4. Nov 20, 2009 #3
    Thanks mgb_phys. I read somewhere that the amount of solar neutrinos hitting the side of the Earth facing the Sun are about the same as those being detected on the far side of the Earth. Thanks heaps for the non-technical answer.

    Does the change in the atom change its radioactivity?
  5. Nov 20, 2009 #4
    Depends on the atom and the energy of the neutrino (they have a wide spectrum).

    Generally speaking, even if every single solar neutrino that hit the Earth were to be absorbed, it would take many billions of years to have any appreciable effect on Earth's composition.
  6. Nov 20, 2009 #5
    Thanks hamster143. I think I can consider my questions answered. Thanks to both of you.
  7. Nov 20, 2009 #6


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    correct, there about 50-100,000,000,000 neutrinos per cm^2 per second going through the earth.
    The biggest detector is equivalent to 50,000 tons of rock and only detects 100 per year !!!11

    they interact with only a very few types of unstable atoms to change them - they don't have much effect on normal atoms.
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