Aurora elders from watching or interpreting the messages of ancestors they believed were transmitted through an aurora. "[[Bulfinch's Mythology]]" relates that in [[Norse mythology]], the armour of the [[Valkyrie|Valkyrior]] "sheds a strange flickering light, which flashes up over the northern skies, making what Men call the 'aurora borealis', or 'Northern Lights' ". There appears to be no evidence in [[Old Norse literature]] to substantiate this assertion. The first Old Norse account of "norðrljós" is found in the Norwegian chronicle "[[Konungs Skuggsjá]]" from AD 1230. The chronicler has heard about this phenomenon from compatriots returning from [[Greenland]], and he gives three possible
Aurora explanations: that the ocean was surrounded by vast fires; that the sun flares could reach around the world to its night side; or that [[glacier]]s could store energy so that they eventually became [[Fluorescence|fluorescent]]. In the 1740s [Benjamin Franklin] theorized in his paper "Aurora Borealis, Suppositions and Conjectures towards forming an Hypothesis for its Explanation" that an aurora was caused by a concentration of electrical charge in the polar regions intensified by the snow and moisture in the air: Observations of the rhythmic movement of compass needles due to the influence of an aurora were confirmed in the Swedish city