Stand beneath the shimmering curtains of the northern lights — the aurora borealis — and you will never forget the experience. They are, without question, the most hauntingly beautiful and unearthly of all natural phenomena.
A typical auroral display begins in the northeastern sky as a diffuse glow, followed by an arc that gradually brightens. As the arc drifts southward (for viewers in the Earth's Northern Hemisphere), new ones may form in its place. Within the arcs may appear intricate ripples and curls that dance along the arc, giving the impression of curtains blowing gently in the breeze. And their colors can be stunning, ranging from brilliant yellow-green to crimson, purple and sometimes even blue.
Such displays have mystified and inspired sky watchers for ages. Some tribes of North American Indians believed the aurora to be the light of lanterns carried by spirits seeking the souls of dead hunters. In Europe of the Middle Ages, the lights were believed to be the breath of brave soldiers who gave their lives as they battled forever in the skies for king and country. And the Aborigines of Australia believed the aurora australis (the southern lights) to be the dance of gods across their southern sky.
See them just once and you'll understand completely.
Today, of course, we strive for a more scientific appreciation. We now know that these mystical lights owe their origin to the sun. Our star violently belches into space electrically charged particles; some are captured by our planet's magnetic field and slam into the polar regions of our upper atmosphere, causing atoms of oxygen and nitrogen to glow a variety of undulating colors.
Sky watchers in arctic regions are treated to these magical lights quite frequently, but those in more southerly locations aren't excluded completely.
In fact, during the most recent solar maximum in 2012-2013, the lights appeared several times as far south as Florida, Texas, Arizona and Southern California. From there they appear to the eye as a slowly undulating glow of gray, but can sometimes take on a deep crimson color.
If you want to the lights in all their glory, however, you must travel far to the north, to places such as Alaska, Iceland and Norway.
Wherever you live — or wherever you travel this year — keep your eyes to the sky, for the northern lights are, indeed, nature's greatest light show and are coming soon to a sky near you!