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Discharging a capacitor - the Van Allen radiation belt

  1. Aug 17, 2011 #1
    I've seen inner and outer Van Allen belt drawings that have the inner belt consisting of protons and the outer belt consisting of electrons. I am guessing this is due to differences in the mass density or the charge density differences of the two.

    So we have charge separation in the Van Allen belt, a potential difference, and a build up of this charge is all we need to reach the critical voltage to cause a current to flow.

    What would it take for the Van Allen radiation belt to discharge: solar storm, cosmic dust, distant gamma ray bursts? Anyone have data on the volume, charge density and other physical properties of the Van Allen belt?

    Because I was wondering if a possible bolide impact or volcanic eruption could cause a discharge. These would have to be significantly large events so I am trying to find out just how big they would have to be.
  2. jcsd
  3. Aug 17, 2011 #2
    I am not a expert in the area, but I don't think there are huge discharges between the outer and inner belts for the following reasons:

    1) The particles in the belts are not just floating is space. They are trapped by the earth's magnetic field. That is why the belt's exist in the first place and the why the particles don't just float away or gravitate to earth's surface.

    2) The distance between the rough outer edge of the inner belt and the inner edge of the outer belt is about 10,000 km. This distance is so large that the electrostatic force between a single electron and a single proton this far apart is negligible.

    3) The particles in the belts are moving at high speed, so you can't treat the system as an electrostatic system like a capacitor.

    4) The belts discharge gradually (leak) by interacting with the atmosphere.
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