Finally … FINALLY … I am going to do a post just on the most magical of magical beauties of Alaskan nature: The Aurora. This is a post I have been wanting to do for months, but held off waiting for a day after a good Auroral Event to describe it better. While I saw it a few times last winter, I have yet to see it this winter. I’m tired of waiting, and maybe if I do post this it will actually come out for me.
The Aurora, also known as the Northern Aurora (the thing in the sky, not the drum corps), also known as the Northern Lights, also known in the Northern Hemisphere’s full title of Aurora Borealis (Aurora Australis in the Southern Hemisphere), is as much an identity to Alaska as anything else you can connect to Northern Latitudes. The aurora paints the winter night sky with greens, blues, reds, and yellows. They appear like ribbons or curtains of colors, and typically move sometimes subtly sometimes constantly. I can post pictures, but my pictures wouldn’t do it justice (good pics can be found if you Google Aurora). Many people have told me that seeing the Aurora is on their bucket list, and if it isn’t on yours then you don’t know what a bucket list is. I love the Aurora for a number of reasons, in no small reason for the great combination of both the analytically side of my brain and the artistic side. It is this magical, dancing painting jumping over the night sky created by a complex series of astronomical events that is still hard to understand and predict. It is predictable of when, where, and how often you will see it; but you still can miss it easier than not. Sure, it’s not strictly an Alaskan thing, but God sure does seem to want to give it to us more often than the rest of y’all.
One misconception about the Aurora is that it is connected to Snowy or Freezing Conditions — that would be like saying New Years Day lands where it does because of the Football Season, both happen they just happen to line up as well. The aurora is actually happening constantly, 24 hours a day, 7 days a week, 365 days a year. It stays in an Auroral Zone, typically 3° to 6° latitude and different distances from the poles, and normally north of the Canadian Boarder (or for you Europeans normally in Scandinavia; and for you Southerners, south of Tasmania). While auroras can be quite bright, never have they been known to be bright enough to be seen during daylight hours. Since the Auroral Zone typically sees 20 or more hours of daylight and evening-long twilight it’s nearly impossible to see the Aurora during the summer. Conversely, since it’s dark for so long during the winter, the casual observer is more likely to spot an aurora during the winter — that’s why it gets it’s frosty reputation. Auroras are actually strongest around the equinox (September & March) but for reasons that scientists haven’t figured out completely yet. It is predictable, and many of us not only have the aurora forecasting website sending us alerts, but even have the forecast app that shows us all the technical data that goes into the forecast.
We don’t do so well on Aurora watches here in Anchorage, seeing it about 5 to 10 times during a year. For one, we are just south of the natural auroral zone, where 20 miles as the crow flies does better; but we also have more cloudy conditions during the winter than Alaska’s interior. Fairbanks, AK does much better — between fewer clouds, the typical aurora band hanging over the city, and longer nights you are more likely to see it than not on any given night during the winter — so, their main source of winter tourism is Aurora seekers. Chena Hot Springs, a natural spa resort 50 miles north of Fairbanks, is known for being one of the best viewing locations as it is away from city lights and deep into the optimum viewing locations — it’s extremely popular with Asian tourists who have a belief that children conceived under an Aurora are more likely to become boys (which leaves us joking sometimes that you need good sanitizer when visiting Chena as you never know in which part of the spa “conceiving” is taking place).
Now for the difficult / fun part — explaining what the hell the aurora is! In short, it’s an interaction between charged particles ejected from the sun hitting the earth’s atmosphere. Photons arriving in the upper atmosphere (50mi or 80km above sea level) collide with nitrogen and oxygen forcing them to change their ionic structure, a process that emits energy at wavelengths visible to the naked eye. The photons are directed to polar regions due to their magnetosphere and solar wind carry-able properties until the reach a critical velocity to affect the oxygen and nitrogen. Since the earth’s geomagnetism is variable, changes in it, typically caused by significant atmosphere weather like large electrical storms, can increase or decrease the rate at which photons will interact with the the atmosphere. If you are still reading at this point, I dare you to leave a comment below that says ‘boo-yeah, I didn’t lose my brain in the analytically part’. The photons are a result of solar storms, such as solar flares, and take approximately 48 to 96 hours to arrive at Earth. This all means an auroral event is predictable based on a solar event, the solar wind velocity carrying the magnetosphere particles, and the current geomagnetic conditions of the planet.
So yeah, an aurora is a complex event.
But still, the beauty of an aurora event, from the most subtle to the most dynamic, is utterly mind blowing. Those lights up in the sky, they grow, they shrink. They turn green to yellow to red. They dance, the hold they wander. They appear, they disappear, they tease. In one of the greatest shows I ever witnessed, I saw one ride across the sky like a ribbon trailing a team of horses, until they grew and lifted to staggering breadth and depth. Then when a swoop of light, turned & circled directly above me like a vortex of emerald sheets swishing about. What makes it more stunning to me is how it does it so silently. For a person who has spent most of his life seeing the pageantry of combining music with visual, to watch a visual media dance and move with such grace to the silence of the world takes my breath away.
My first glimpses of it were as a kid when we it reached south enough to be seen over Southern Wisconsin, still trying to figure out what we were seeing out of a car on a cold dark night. When I was in college in Michigan’s Upper Peninsula, they were visible about as much as they are up here in Anchorage — which is to say 5-10 times a year. Typically (and this was back in the day of crappy cable TV) we would know it was a good Aurora night if the cable channels started going out. We would run to the window, and there they were in the sky. I saw the aurora on my first overseas flight, when we were over the Northern Atlantic on route to England. I can remember three or four times I caught it during my first winter up here – the grandest when the sky went full on emerald green the night before St Patrick’s Day leading me to say “Chicago may paint their rivers green, but Anchorage, God paints the sky green”.
I doubt tonight will be the night I see it this winter — for one we are getting heavy snow through the weekend, so forget about seeing any part of the sky; and the forecast call for only a “Moderate” (or 3 of 10) level of activity. But a big flare could happen today, the clouds could break tomorrow, and we could be dancing under the emerald skies by the end of the weekend.