User:Asrin.n

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Appearance and relation to magnetism

What does it look like? Most often, you see greenish white ribbons stretching across the sky, roughly from east to west, usually with waves in them. In Fairbanks they could be overhead, in northern Norway or Sweden too, sometimes even in Winnipeg. Further south those ribbons tend to be near the northern horizon. And if you look closely at them, you will note that they contain many parallel rays, running across their width (see picture below).

Two things about those rays. One, the bright ones fade while dim ones brighten instead--a bit like flames in a fireplace, and just as mesmerizing. Some auroras are deep red, and these may be just a shapeless glow--or they may have rays, too. And second, the direction of those rays is related to the magnetism of the Earth.