In Norse mythology the Valkyries (immortal, war-like virgins) would come galloping across the night sky upon their horses equipped with helmets, spears and armor that would glow and shimmer in the darkness. These lights, colored red, blue, violet and green, would spread in curtains from horizon to horizon, amazing the mortals below. This is how the Vikings explained a phenomenon we now call the aurora borealis, or the Northern Lights.
Yesterday's Twitter: Valkyries
From yesterday's Twitter @NorseMythNews, here are the Valkyries over Sweden in a photo by Mia Stålnacke:
You can find out more about the "northern lights" and the Valkyrie here: The Northern Lights. Here is the opening paragraph: