The "Northern Lights", at their most dazzling from December to March when nights are longest and the sky darkest, can usually be seen even as far south as Juneau.
Undulating ribbons of light may shimmer in the sky for hours, like glowing, dancing curtains of green, yellow and orange or dark red, or magnificent veils with a full spectrum of colors, and with the altitude of its lower edge 60 to 70 miles above the earth.
Or the aurora may last 10-15 minutes, twisting and turning in patterns called "rayed bands", then whirling into a giant green corona in which rays appear to flare in all directions from a central point, and finally fade away.
The rarest aurora is the red aurora, like the one of February 11, 1958, which is still talked about today.
An Eskimo tale records that the northern lights are spirits playing ball in the sky with a walrus skull. Another legend, calls them the flaming torches carried by departed souls guiding travelers to the afterlife.
The scientific explanation is that the aurora is a physics phenomenon taking place 50 to 200 miles above the Earth. Solar winds flow across the Earth's upper atmosphere, hitting molecules of gas lighting them up much like a neon sign.
To study the phenomenon, researchers at the University of Alaska Fairbanks shoot rockets loaded with special instruments into the aurora from a launch pad at the Poker Flat Research Range, 30 miles northeast of town.
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