- Grades: 3–5, 6–8
Theme: The Arctic Atmosphere
The IAP team is traveling in 24 hours of light these days, but the aurora borealis, a magical part of the Arctic winter nights cannot be overlooked! Named for the Roman goddess of the dawn, Aurora, the aurora borealis is a sea of light seen in the night sky of the Arctic. (The aurora australis is the aurora of the Southern Hemisphere.) It is a magnificent natural phenomena and leaves the viewer with a sense of awe and wonder. Legends for centuries have evolved around the aurora borealis.
It has only been relatively recently that the cause of the aurora borealis has been understood. The surface of the sun is in a state of constant explosion. The largest explosions, known as prominences, send charged particles called electrons millions of miles into space. Sometimes these explosions are so great that the electrons reach the upper atmosphere of earth and are trapped in the strong magnetic fields that surround earth. When these fast moving, warm electrons come into contact with the colder gases in the upper atmosphere, the aurora borealis takes place.
The aurora actually is located high in the atmosphere of the earth in the ionosphere. Its lower end is about 65 miles above the earth and it can stretch to as high as 300 miles above the earth. It has a curtain or ribbon-like form which hangs vertically. It sways and folds and appears to be dancing in the night sky. A very active aurora has an increased number of folds and develops a variety of colors. The aurora is huge and, while it appears to be a local phenomena, it actually can cover a huge part of the polar region.
But, where, O Nature, is thy law?
From the midnight lands come up the dawn!
Is it not the sun setting his throne?
Is it not the icy seas that are flashing fire?
Lo, a cold flame has covered us!
Lo, in the night-time day has come upon the earth.
What makes a clear ray tremble in the night?
What strikes a slender flame into the firmament?
Like lightning without storm clouds,
Climbs to the heights from earth?
How can it be that frozen steam
Should midst winter bring forth fire?—M.V. Lomonosov, Aurora and Airglow, ed by B.M. McCormac, translated by K. Chapman, New York: Reinhold, 1967, p. 20.
Alaska Geographic has published a wonderful book on the aurora borealis. It was first published in 1979 by the Alaska Geographic Society and is called Aurora Borealis: The Amazing Northern Lights, Volume 6, Number 2.