How the Aurora Borealis Works

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‘The aurora borealis, also called the Northern Lights, is a multi-colored brilliant light show in the Earth's atmosphere that is caused by the collision of gas particles in the Earth's atmosphere with charged electrons from the sun's atmosphere. The aurora borealis is most often viewed at high latitudes close to the magnetic north pole but during times of maximum activity, they can be viewed very far south of the Arctic Circle. Maximum auroral activity is rare however and the aurora borealis is normally only seen in or near the Arctic Circle in places like Alaska, Canada, and Norway. 

In addition to the aurora borealis in the northern hemisphere there is also the aurora australis, sometimes called the Southern Lights, in the southern hemisphere. The aurora australis is created the same way as the aurora borealis and it has the same appearance of dancing, colored lights in the sky. The best time to view the aurora australis is from March to September because the Antarctic Circle experiences the most darkness during this period. The aurora australis is not seen as often as the aurora borealis because they are more concentrated around Antarctica and the southern Indian Ocean. 

Predicting the Aurora Borealis - Today modern technology allows scientists to predict the strength of the aurora borealis because they can monitor the strength of the solar wind. If the solar wind is strong auroral activity will be high because more charged particles from the sun's atmosphere will move into the Earth's atmosphere and react with the nitrogen and oxygen atoms. Higher auroral activity means that the aurora borealis can be seen over larger areas of the Earth's surface.

Predictions for the aurora borealis are shown as daily forecasts similar to weather. An interesting forecasting center is provided by the University of Alaska, Fairbanks' Geophysical Institute. These forecasts predict the most active locations for the aurora borealis for a specific time and give a range showing the strength of auroral activity. The range begins at 0 which is minimal auroral activity that is only viewed at latitudes above the Arctic Circle. This range ends at 9 which is maximum auroral activity and during these rare times, the aurora borealis can be seen at latitudes much lower than the Arctic Circle.

Importance of the Aurora Borealis - The aurora borealis has been written about and studied for as long as people have been living in and exploring the polar regions and as such, they have been important to people since ancient times and possibly earlier. For example, many ancient myths talk about the mysterious lights in the sky and some medieval civilizations feared them as they believed that lights were a sign of impending war and/or famine. Other civilizations believed the aurora borealis was the spirit of their people, great hunters and animals like salmon, deer, seals, and whales (Northern Lights Centre).

Today the aurora borealis is recognized as an important natural phenomenon and every winter people venture into northern latitudes to watch it and some scientists devote much of their time to studying it. The aurora borealis is also considered one of the Seven Natural Wonders of the World.’ (Source) 

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