urora - God's Night Lights
| The Aurora Borealis, or as we Alaskans call them, the "Northern Lights," is an amazing phenomenom. It is no wonder that the peoples of Northern climates have long had myths and legends about them. They occur in the upper atmosphere around the North Pole every day and night, but are only visible in the months which have dark night skies. They also occur around the South Pole; there called the Aurora Australis or "Southern Lights." In Fairbanks the aurora can be seen an average of 240 nights a year, if you know where in the sky and at what time to look for them.
The aurora is produced by charged electrons and protons striking gas particles in the earth's upper atmosphere. These electrons and protons are released through sunspot activity on the sun and emanate into space. A few drift the one-to-two day course to Earth, where they are pulled to the most northern and southern latitudes by the planet's magnetic forces. The color of the aurora varies, depending on how hard the gas particles are being struck and the types of particles hit. Auroras range in color from pale green (most common) to red, blue and purple. They occur in patterns, sometimes arcs like draperies blowing in a breeze, sometimes patchlike pulsing masses of light, and sometimes the sky is just filled with light. They concentrate in two bands roughly centered above the Arctic and Antarctic circles. These bands are about 2,500 miles in diameter. The displays seem close to the observer, sometimes seeming "close enough to touch." Actually, they can sometimes begin as low as 40 miles above the earth's surface, but generally begin about 68 miles above the surface and extend hundreds of miles into space! It is interesting to note that aurora activity above the north and south poles occurs at the same time and they are mirror images. The space shuttle has taken many photos of them in the past few years. |
These are pretty typical shots of the Aurora seen in Fairbanks. These aurora
photos by Jan Curtis are borrowed from his Aurora's Northern Nights web site.
Please visit his website to view more excellent Aurora Borealis photos.
| In northern latitudes the greatest occurrence of auroral display is in the spring and fall months, owing to the tilt of the planet in relationship to the sun's plane, but displays may occur on dark nights throughout the winter. If sunspot activity is particularly intense and the denser-than-usual solar winds head to Earth, the resulting auroras can be so great that they cover all but the tropical latitudes. However sunspot activity is such that it will be many years before the numerous, brilliant displays of the late 1950's are regularly seen again.
In March 1989 I was traveling the Parks Highway driving home to Fairbanks from Anchorage. Passing through the Alaska Mountain Range, all at once the entire sky glowed red. We stopped the car to watch, and saw an intense red aurora display that filled the sky for a very long time. My father told me that once, when he was growing up near Portland, Oregon, they had seen some aurora activity in the northern sky. Unfortunately, I don't have the camera equipment needed to film the aurora, but I found several interesting links online with photos and more information. |
urora Pictures from Earth Orbit
Southern Lights (Aurora Australis) displays seen from the Space Shuttles orbiting Earth.
Sinuous Loop, May 1991 
