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AURORA
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Tromsø, Norway.
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Photography: Tor Even Mathisen
43 | Music: Per Wollen
44 | Vocal: Silje Beate Nilssen
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tittentem.no
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Auroras are associated with the solar wind, a flow of ions continuously flowing outward from the Sun.
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The Earth's magnetic field traps these particles, many of which travel toward the poles where they are accelerated toward Earth.
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Collisions between these ions and atmospheric atoms and molecules cause energy releases in the form of auroras appearing in large circles around the poles.
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Auroras are more frequent and brighter during the intense phase of the solar cycle when coronal mass ejections increase the intensity of the solar wind.
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oxygen emissions
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Green or brownish-red, depending on the amount of energy absorbed.
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nitrogen emissions
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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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The stars are putting on their glittering belts.
69 | They throw around their shoulders cloaks that flash
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The Valkyrior are warlike virgins, mounted upon horses and armed with helmets and spears. When they ride forth on their errand, their armour sheds a strange flickering light, which flashes up over the northern skies
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