Fulfilling a childhood dream!

Physics in action! Here's an explanation for why the Northern Lights happen (http://en.wikipedia.org/wiki/Aurora_(astronomy)):

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

oxygen emissions

Green or brownish-red, depending on the amount of energy absorbed.

nitrogen emissions

Blue or red. Blue if the atom regains an electron after it has been ionized. Red if returning to ground state from an excited state.

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A site that I checked for forecasts http://www.gi.alaska.edu/AuroraForecast.

I didn't get to see blue, that's rare, but I was able to see red. Green was all around. It's too bad that red happened too quickly for me to capture digitally, so it's going to have to remain in my memory.

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