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Auroral mechanism

  1. Jan 21, 2013 #1
    This video [http://www.youtube.com/watch?v=7Mz2laHjVoQ] explains the mechanism behind aurorae, but i need some clarifications:

    1) Is it true that aurorae can be produced only by some ejecting chunks of plasma and NOT by solar wind (flow of particles)? If not true, then how solar wind can contain magnetic field?

    2) Why particles at first reconnection move quickly towards the poles and not just hover around (at second reconnection, behind the earth, magnetic field lines are stretched, but at first, when chunk of plasma approach the earth, the lines seem to be "relaxed")?
  2. jcsd
  3. Jan 24, 2013 #2
    Solar wind is composed of charged particles. Magnetic fields are produced as a result of electric currents, which are the flow of charged particles. As long as the solar wind has charged particles, which it always does, it will produce a magnetic field.

    The Aurora is a result of the interaction of the solar wind particles on the atoms of gasses that make up the upper atmosphere.

    The particles are accelerated as they travel across the earth's magnetic field.


    A quote from Wikipedia:

    "Auroras result from emissions of photons in the Earth's upper atmosphere, above 80 km (50 mi), from ionized nitrogen atoms regaining an electron, and oxygen and nitrogen atoms returning from an excited state to ground state.[9] They are ionized or excited by the collision of solar wind and magnetospheric particles being funneled down and accelerated along the Earth's magnetic field lines; excitation energy is lost by the emission of a photon, or by collision with another atom or molecule"

    Last edited: Jan 24, 2013
  4. Mar 1, 2013 #3
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