Is it a bird? Is it a plane? No, it is the aurora borealis or better known as the Northern Lights. These lights are easiest seen in between the degrees of 66 and 69 north. Northern Alaska, Canada, Russia, Scandinavia, and parts of Greenland are the home to this Northern Lights theater. This does not leave the rest of us Southerners out though. Northern Lights have been witnessed as far south as Mexico and when atmospheric conditions are right. The aurora australis or Southern Lights would be the light show for the southern hemisphere.
The Northern Lights are also visible from space. Peak activity is close to the equinox months of September, October, March, and April. Green, yellow, pink, red, and blue are some colors that paint the skies. Some even say it looks as if the sun is rising but in the wrong direction when viewing these spectacular lights. Now for the scientific stuff. The shifting swirl of colors comes about when charged particles from the magnetosphere collide with atoms in the earth's upper atmosphere. Extra energy absorbed is expressed as light. The sun causes hydrogen and helium to fuse, and protons and electrons are shot into space. The solar wind then blows the stream of particles past earth. The earth's magnetism lines draw the particles toward the magnetic north and south poles. The particles collide with the gas atoms when they get to the ionosphere and they emit light.
The type of gas the particles collide with with control the color of light they emit. Emissions from atomic oxygen will have a greenish and dark red glow. Atomic nitrogen results in light blue. Purple comes from molecular nitrogen. When the kp index, a measure of electromagnetic activity in the atmosphere, is a reading of two or higher, then the Northern Lights might be good for viewing. Many times when the Northern Lights are viewable in far southern locations, news stations will give a heads up to viewers who wish to witness these lights.
As beautiful and mysterious as the lights are as they dance in the sky, past generations have feared them. They were often seen as a symbol of impending doom and were wrapped in superstition. They are entwined in folklore and myths. The Inuit people who live in the northern latitudes claim the lights are past ancestors. Other myths they have is the aurora borealis is the story teller of the past and it will tell of what the future holds. No matter what all the scientific or folklore has to say about the northern lights, this fact remains; They are a breathtaking event put on by nature. The popping and cracking noises they sometimes emit and the whirl of lights cast against the heavens above can pale many man made events. So the next time the lights are going to be on the marquee in your area, don't miss this show, even if it means staying up way past your bedtime.
References
Aurora Borealis. (n.d.). Retrieved January 24, 2015 from http://aurora-borealis.us/
Wong, H. (2013). Best places to see the Northern Lights. Retrieved January 24, 2015 from http://www.cnn.com/2013/11/20/travel/best-northern-lights/index.html
I like this video of northern lights. It is wonderful Northern lights trip
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