The aurora borealis, or the northern lights, are a striking light show. These lights have been dancing in the heavens above the northern regions for a long portion of Earth’s history. They have fascinated human beings for as long as we’ve been around to see them. The lights are a tourist destination, a source of myth, and a generally striking sight. Let’s break down the truly fascinating, Northern Lights!
The Mythology
The aurora borealis was named by Galileo in 1619 after Aurora, the Roman goddess of the dawn, and Boreas, the Greek name for the north wind, but the phenomenon has had a number of other names throughout human history. The Cree, a Native American group that lives mostly in Canada, called it the Dance of the Spirits. Other tribes like the Inuit and northern Algonquin held that the spirits of the dead could be seen in the aurora.
History
Unlike many phenomena eventually explained by science, the aurora is so nebulous that the scientific community went through a large number of eventually disproven theories before hitting on a proper explanation. Benjamin Franklin thought it was caused by snow and moisture concentrating electrical charges at the poles. In the twentieth century alone, the auroras borealis and australis were theorized to be caused by beams emitted from the sun, by solar wind alone, and, in the memorably named “leaky bucket theory,” by overflow of the Earth’s Van Allen radiation belt.
How it Works
Solar winds are involved in the fantastic-looking result that is the aurora borealis. Solar winds come directly from the Sun containing highly charged electrons, reaching Earth after a trip of a bit less than two days at around a million miles per hour to follow the lines of magnetic force generated by the Earth and flow through the magnetosphere. These particles ionize photons in Earth’s upper atmosphere, collisions causing the visual effect of the aurora. Nitrogen particles cause blue, violet and red, oxygen red and green, each depending on altitude and energy absorbed.
Related articles: The Northern Lights of Denmark also What Causes the Northern Lights
Featured Image from Lightscape/Unsplash
