The aurora borealis is an amazing phenomenon to behold. The physics that causes it to happen (simply put, electrons from solar wind colliding with oxygen and nitrogen atoms in the atmosphere causing them to emit light) does not enter into the mind as you watch the shifting patterns of light dance across the sky. On a clear night, the contrast between the ribbons of color and the dark starry sky is striking. As you watch you appreciate the Inuit’s belief that the lights are their ancestors playing. If you whistle, you can get them to come closer, but do not whistle too loud or long because they may come down and take you up to join them. Though the eye does not always catch the subtle colors (our night vision is not overly color sensitive), the camera can capture a greater range of colors: green, reds, and blues. This allows us to share beautiful images.
On a cold cloudy day, ice crystals in the clouds cause refraction of the aurora causing the entire sky to appear green. The snow on the ground reflects the color causing it to take on a greenish tinge. Standing in the boreal forest immersed in this eerie green glow, you feel like you have been transported into a horror movie. Though, even on cloudy days, bright bands of aurora create interesting contrasting patterns against the green background sky.
Pictured: images showing the “green snow”, the red upper aurora bands, and moon rise
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