The Aurora Borealis In Alaska
The Aurora Borealis in Alaska is created by sun spots and solar winds colliding with our earth's atmophere. The result: glorious colors in the northern sky.
Old Scandinavian folk tales claim that the Aurora Borealis is made up of many reflections bouncing off the shields of warrior maidens, or Valkyries, as they bring the souls of deceased heroes through the gates of Valhalla. The Hudson Bay Inuit believe the northern lights are torches guiding the dead into the spirit world. In Europe the northern lights warned of plagues or impending illness, were harbingers of war, and were relied upon for weather forecasts. Even Aristotle made reference to this heavenly phenomena in his writings, claiming auroral lights were “liquid fire.”
And in Northern Canada, present day Aurora watching has become something of a minor tourist industry, attracting many interested viewers.
The name itself, Aurora Borealis, is derived from the locations where the phenomena occurs, usually above 60 degrees in the northern or southern latitudes. The Aurora Borealis is the lights seen in the northern skies while Aurora Australis are those seen in southern locations. Aurora Polaris, or polar lights, refers to both.
Auroras are created by sun flares. Highly charged atoms and electrons travelling on solar winds speeding toward Earth at 500 miles per second collide with the planet’s magnetic field. As they sweep past and react with the atmosphere, these particles turn into light that the human eye sees as the Northern Lights.
The rainbow-like colors are created by a combination of the following: a variety of atmospheric gases, their electrical state (ionized or neutral) at the time the solar flares strike, and the energy behind the particles when they hit. High altitude oxygen (200 miles up) colors the aurora borealis a brilliant red. Oxygen at 60 miles up gives off the more common yellowish-green glows. Ionized nitrogen produces blue light, neutral nitrogen red as well, though not as bright. These nitrogens are also responsible for the purple rings and rippling edges associated with the northern lights.
The length of the each display varies from 10-20 minutes to a few hours. Once an auroral sub-storm is produced, the first faint glimmers seen in the horizon soon transform into arcing pulses of light. These arcs are aligned with the magnetic field and begin to streak further into the sky until they seem to meet directly overhead, forming a domed curtain. Then the colors suddenly break apart into curls, shimmers, fingers, or fiery pulses of either diffuse multi-colored lights or patches of more neutral greens, yellows, and blues. The lights seem to change and turn on and off every 5-10 minutes.
Other Aurora Borealis facts:
1) The lights extend 600 miles above the planet.
2) People say they’ve heard sound coming from the aurora. Scientists say it’s impossible. Sounds generated in space take too long to reach Earth, and air inside auroral displays is much too thin to support sound in the first place.
3) Cold does not make the northern lights any brighter.
4) Sunspot activity reached a peak in 1991, creating large numbers of auroral displays that year.
5) It’s unclear if increased solar activity has added to global warming, but scientists agree that when there are fewer sunspots and no aurora, it’s always colder in northern regions.
Aurora Borealis has been visible for as long as mankind has been watching the skies. No matter the superstitions or dry scientific facts, these lights are wondrous spectacles of heavenly beauty, a phenomenon that is truly nature’s light show.