It was Halloween and the sky looked like a creature. Exactly which creature, the astrophotographer was unsure (but possibly you can suggest one ). Exactly what caused this eerie apparition in 2013 was sure: one of the best auroral displays that year. This spectacular aurora had an unusually high degree of detail . Pictured here , the vivid green and purple auroral colors are caused by high atmospheric oxygen and nitrogen reacting to a burst of incoming electrons . Birch trees in Tromsø , Norway formed an also eerie foreground . Frequently, new photogenic auroras accompany new geomagnetic storms .
Almost Hyperspace: Random APOD Generator
Media Credits & Attribution
Image Credit & Copyright: Ole C. Salomonsen ( Arctic Light Photo )