The light comes up over the northern ridges like smoke catching fire: green first, then teal, then a pale rose along its hem. Most nights that is all it does. It ripples, it fades, and the people below call it beautiful, or call it a warning, and go in to bed. On other nights the Veil goes wrong. The curtains stop swaying and set into straight edges, folds as clean as cut glass, angles stacked on angles across half the sky. A dog barks, and you hear it a breath before the dog lifts its head. A harp hanging on the wall begins to hum, and no hand is near it. You think a thought you have already thought, word for word, and then once more. Ask two watchers where the light stood, and they point to different stars. They call it a veil only because nobody has found a better word for a door that keeps moving.
What watchers see
The Aurora Veil is the unstable boundary, or phenomenon, bound up with the crossings of the Aethyr, with resonance, with the northern lights, and perhaps with death and the oldest powers of the world. "Veil" is a picture that scholars and singers find useful, not a settled truth. It can be watched in the sky, met at damaged gate sites, and measured only indirectly, through what it does to resonance. Maps draw it as a band of light along the north, never as a border, because its place shifts with the weather, with the watcher and with its own unrest. Aethra Above may lie beyond it, through it, or along some path the word "veil" cannot describe.
Every people reads its disturbances differently. The Aethyr have refined methods for studying them, but refined is not the same as complete.
What is told
The first great crossings through the Veil began the Age of Falling Light. In the War of the Burned Constellations, resonance weapons tore parts of it, worst of all above the Ember Crown. Since then its stability has been the reason given for every Aethyr policy at once: permanent control, careful restraint, or departure. Damage to the Veil is one of the few dangers all the Aethyr leaders agree on; what caused it and how to mend it, they do not. Some fear that reopening the Last Gate would bring the way home. Others fear it would bring the Last Storm.