How many infinite pieces must come together in exactly the right way for something to happen? Think about a child…an egg and a sperm met…but so much had to happen in just the right way for that particular egg to meet that particular sperm to make that particular child. Whether it is the conception of a child, the meeting of your future spouse, or, in my world, the dance of the Lady Aurora, we generally don’t think about all the things in play to make something happen, it just does. This tendency enables us to take things for granted…the flick of a switch brings us light, the turn of a key enables us to take a road trip, the tap of a card pays for that shiny new purchase. We seldom stop to think about how any of it works…until the moment it doesn’t. Then panic ensues and phone calls get made demanding satisfaction. Never do we stop to consider that it is more miraculous that something worked in the first place and infinitely less miraculous that it doesn’t.
I am often asked how I know when to head out with my camera. Some assume I simply stay up all night on the off chance and am inordinately lucky. Others assume I never sleep because Auroras only happen in the middle of the night (wrong). Even others proclaim I must live right under the Aurora because they live 25 kilometres away and have never seen them (insert face palm here). Others comment that I must have a really good camera, to which I reply, “I do, and I taught it everything it knows” (although there is still so much to be learned).
I have been interested in the night sky for as long as I can remember. Growing up in Nova Scotia (yes, I remember the total eclipse of Carly Simon fame), I later traded in the surf and salt air for the magnificent skies of Northern Alberta. I would catch the Aurora simply by chance and would marvel that such majesty existed. Several years ago I was gifted my camera gear by my hubby and my journey as an Aurora photographer began. I joined the Alberta Aurora Chaser Facebook group, a collective of amazing like-minded folk who willingly share their knowledge and expertise and who stand with me, virtually connected, in the field as I navigate the dark – never really alone. Through their expertise I learned to read space weather (in the most basic sense) which added an important tool to my arsenal.
The Aurora is caused by activity on the sun’s surface. A good, strong solar flare, particularly the type known as a coronal mass ejection (or CME), grabs the Aurora chaser’s attention. This can create a geomagnetic storm that results in powerful Northern Lights even at lower latitudes. The CMEs can reach a speed of up to eight million km/h and take about 20 hours to reach Earth. One might think at that point you clear your diary, give up any notion of sleep, charge your camera batteries, and prepare your excuses to your boss as to why you fell asleep in the meeting. Not quite. So many other things have to happen in just the right way.
As I write this I have just received an alert that the Aurora has reached KP6 (G2 storm) conditions. Normally this news would have me grabbing my go-bag and equipment and starting the car like the mad woman in the IKEA commercials. However, the sun is shining and I sit with my morning coffee wishing I could find the solar off button. Rule number one, it has to be dark. Auroras can dance by day, much to my chagrin.
Solar wind speed, density, and KP conditions all come into play in the road production of the Auroral dance. (KP is the measure of the degree of disturbance in Earth’s magnetic field). To put it simply, the stronger the wind, the higher the density, and the more negative the BZ’s(interplanetary magnetic field or IMF), the better the show! But wait…those pesky BZ’s can throw a monkey wrench into the whole night. Just when you think all your ducks are in a row, the BZ’s will start to trend north and Netflix begins to look like a viable option. The BZ’s may bounce back and forth between negative and positive – jittery, if you like – and then suddenly trend south. If it trends south long enough, the Aurora dances. It might be a short sweet glimmer or a quick bold dance and then – poof! – gone again as the BZ’s trend North. The patient chasers wait and watch, for it can just as easily turn around and become a fast moving, bold show of dancing lights that last through the entire night. I am fortunate to have my field of view right in my own backyard and it is but a 2 minute drive to catch a wide open country horizon. Sometimes I don’t get past my own front door. There I stand weighing the odds…do I grab the photo now – in town battling streetlights, or risk the 2 minute drive by which time the Lady may have lost her brilliance and slowed to a mere barely visible splotch in the sky or winked out entirely? I’ve been fooled before, she can be a wicked temptress! I feel for my fellow chasers, who, on the strength of a promise, travel for hours to await the great show that never was.
To summarize, for an Aurora show to occur, there must be an earth-facing solar event, it must be dark, there must be sustained negative BZ’s, a strong high density solar wind, and the higher the KP index, the lower the latitudes that it will come into view. Whew! Let’s say all these factors are nicely in play. Grab the camera? Wait for it….
The Aurora dance way above our earthly weather so clouds unfortunately play a major factor in what we are able to see. I swear the clouds are able to read the same space weather app and arrive just in time to crash the party. Partially cloudy nights are the worst…the possibility exists that they could clear at any moment and I wear a path to my window checking and performing test shots with my camera to see if a window of opportunity has opened up. So add clear skies to the list of pieces to this celestial puzzle. When I’m looking through my catalogue of Aurora events, I feel a deep sense of gratitude that all the right things came into play at the right moment to produce that which I see on my screen. I consider myself a fortunate witness to the occasion, in the right place at the right time, thinking of how many times the Lady Aurora has danced over my oblivious sleeping head. Because, even after having described (in the most rudimentary of ways), what must happen for Auroras to occur, there are always those times – the most magical of times – when you get up in the night and look out the window and there she is – with not a scrap of data to support her appearance, she dances.
I understand the science, but I still believe in magic.