Tuesday, June 23, 2015

Chasing the Aurora Borealis in the Eastern Sierra, June 23, 2015

I read online yesterday that a particularly intense solar magnetic storm might enable the aurora borealis to be visible across much of the United States, as far south as San Francisco and Lake Tahoe. I could see from early results posted from the East Coast and Missouri that the event was progressing as expected.

The aurora borealis tends to be strongest in the location on the earth opposite the sun, and at 11 pm the aurora forecasting apps were showing the strongest magnetic field dipping down in the middle of the United States, so I had roughly one to two hours before that strongest part of the storm would reach us in the Western U.S..

The best visibility of the aurora would be to the north, but I live south of the light pollution from the Carson Valley and Minden/Gardnerville Nevada. There is also the Washignton Fire sending smoke in that direction, so I headed a few miles south then up into the Sierra Nevada to get further from lights and above the smoke.

Partway up the steep road I shot to the north, but the light pollution was too great, so I continued higher.  I tried shooting more to the east to cut out light pollution to the north, and there was a promising increase in green and red color in the sky, but common airglow can cause both of those colors, so I needed to try shooting a sequence of images and create a time-lapse video to see if the red-pink color on the horizon would dance like you see in aurora videos.

Sure enough, there was some aurora color on the horizon, and it gained in strength, shooting upwards into space and dancing across the sky:


I shot the time-lapse video from the high, dry, clear skies of the Sierra Nevada, near the Little Antelope Pack Station above the town of Walker, California: https://youtu.be/NaQiOQrQ_S8?list=PL6012D9822C1BA1E7

For comparison, I also shot the sky more to the south- southeast, to get a reading of the ambient green and red airglow colors in the sky.

It was cool to see the aurora borealis all the way down here along the California - Nevada border.  The forecast for tonight isn't quite as strong, but it's a rare opportunity that is hard to resist, so I may have to go back out and try again!

The rays of red light could be 65 miles high above the earth, and 600 miles north!