What Really are the Northern Lights?

Two nights ago at 11pm I found myself a kilometre down from Bow Falls in Banff, lying on the rivers edge in complete darkness, starring up at my first proper performance of the Aurora Borealis. I had seen the slightest glimpse of the Aurora the night before, but it was only fleeting & just between the valley of two mountains. It seemed more of a dress rehearsal that first night. But this night, I was getting the full show. Original cast and all. Waves of white light with a slight green hue danced for me across the sky. A top performance no doubt, but I still feel like the cast had more to give… I’ll find out in the coming months. I was sitting there marvelling not only at the Aurora itself, but the satellites, shooting stars, lining of the milky way and sparkling stars projecting at me light from a time gone by. All from different times depending on how far away they were. I wondered what stages of the Earth those stars would have been receiving if they could have zoomed up on earth’s little blurry light. Maybe the closest would have been looking at the moon landing mission, the further away, seeing the death of Julius Caesar. The invention of fire… My imaginary reader gets the point. This night also gave me the strongest urge to go camping. Not much beats being away from civilisation with your friends/ family, just soaking in the sap from the trees, morning dew & the spray from the river or sound of the ocean in the morning… mmm. Delicious.

It also made me think… “Daf*k is an Aurora Borealis??” I also really felt like eating a Kit Kat.

So what is it? I’m glad you asked again, imaginary reader! Wow, you really aren’t shy of a question. An insatiable appetite for learning you have!

Luckily again, I have the answer… Or… I know a guy. Called Larry. Larry Page, and he has the answer. All you have to do is type your question into his magical website and people with both bigger and smaller brains than mine have likely weighed in on this exact topic. All with the supreme confidence that their answer is beyond a shadow of the doubt, the correct one.

The Aurora Borealis occurs when charged particles (electrons and protons) collide with gases in Earth’s upper atmosphere. The Aurora Borealis (Northern Lights) can only be seen towards the north pole, where the Earth’s Magnetic sphere is the weakest. There is also the Aurora Australis, which is seen near the south pole. Derived from ‘auster’, meaning ‘from the south’, think ‘Australia’. And of course ‘Borealis’ with a similar etymology – meaning “northern,” late 15c., from Late Latin borealis, from Latin Boreas “north wind,” from Greek Boreas, name of the god of the north wind.

The Northern Lights start with the sun. Solar storms on the surface of our big beautiful sun shoot out huge clouds of electrically charged particles. These particles charge in all directions, some towards our little planet at a dizzying rate of knots. This stream of charged particles (namely protons, electrons and alpha particles), is created by the outward expansion of plasma, from the sun’s outermost atmosphere, called the corona. This stream of charged particles is known as the Solar Wind.

From here, most of this Solar Wind is deflected away by the Earth’s mighty Magnetosphere, which is coincidentally, the coolest word ever. But some of these charged particles are captured in the Earth’s magnetic field and are accelerated into the north or south poles.

And that is where the magic happens. These particles then slam into atoms and molecules in the Earth’s atmosphere, essentially heating them up in the process, in a process called excitation. Think, ‘excite’. It is very much like heating a gas, and making it glow. So what I was looking at by the river, were charged particles from the sun, colliding with atoms and molecules in our atmosphere to create the most gorgeous glow. The wavy patterns or ‘curtains’ of the Aurora are caused from the lines of force from Earth’s magnetic field itself. That’s right. Say it with me. Magnetosphere. Mmmmm.

How about the different colours? Well they all come from the different gasses as they are heating. The two main gasses in the Earth’s atmosphere are oxygen and nitrogen. When heated, these give the Aurora her (or his… As we found out Borea was a Greek god) Different colours.

Oxygen – Green
Nitrogen – Purple, Pink, Blue.

Occasionally, a red will come out, from high altitude oxygen combining with these solar particles. This will only happen when the Aurora is feeling particularly energetic.

So there you have it! That is what I was looking at, and certainly plan to again. Life in all its splendour. Abundant and rich. A cosmic show, performed for goobers like us. You could even say we are very much part of that play. What do you think of that, imaginary reader? Oh.. You’ve dozed off. Not a worry.

I also did finish the night with a Kit Kat from a vending machine.

Wonderful night. Pics below.