Sarah Freiberg
As we enter the New Year, the brisk cold air of January has opened up to us with warm shivering arms. And with it comes the supposedly colder winter nights, in which some say are more welcoming for the Northern Lights. The Northern Lights, for some, gives them a piece of light during the dark nights, reassurance and beauty. All over the world, throughout history many people have come up with different explanations to this colourful phenomenon, but how many people really understand these curious lights?
Before we begin however, allow me to further explain what the northern lights are. Aurora Borealis is a naturally occurring phenomenon which takes place in the northern and southern hemispheres of the globe. They manifest themselves as streams of light that can be observed in the night sky. They are observed in the northern hemisphere, at higher altitudes, for instance ; Canada, Norway, Iceland, Alaska, Finland, Sweden, and Russia.
They become visible starting from late August all the way to the spring. This is due to weather conditions being more stable during these times, but also due to the fact that this phenomenon is much more present during the equinoxes. Essentially, as the earth rotates around the sun, the magnetic field of solar winds differ. During the equinox, there are these types of magnetic breaks or rips which let in these solar and electrically charged particles, these particles collide with the gases in our atmosphere. While they are visible during these times, they are however best visible from November to February as skies are darker, which offers a better viewing and sky-gazing experience.
The Aurora Borealis occurs when electrically charged particles interact with gas particles in the Earth’s atmosphere. These electrically charged particles are emitted from the sun, and make their way through solar winds. Once a very small fraction of these enter our atmosphere, they are pulled towards the Earth’s magnetic poles. When these charged particles and gas particles collide, energy is released in the form of light, essentially as a tiny ray of light. These colours of light can differ based on which gas the charged particle interacted with, but also at which altitude they collided at.
There is a variety of colours the Aurora Borealis emit, the most common one being green. This phenomenon is due to the solar winds hitting millions of oxygen particles consecutively. Although, from time to time, the Northern Lights express themselves in a red light. We don’t experience these as much since we are not as sensitive to the red lights emitted. However, this red colour manifests itself when solar winds collide with oxygen particles that are higher up in the atmosphere. Not to mention, their colour beams aren’t quite as bright nor powerful as those of the green rays. Lastly, purple is a very rare shade that can be observed in the night sky. Purple is essentially obtained when solar winds hit nitrogen atoms with lots of power, although this rarely occurs since the amount of power needed to hit the nitrogen atoms with is massive.
For years we have gazed at the marvel that is the Northern Lights, but since when did we put a name to this phenomenon? Who discovered the Northern Lights? The famous Galileo Galilei was the one who named the Northern Lights, a few centuries back, in 1619. He named them the Northern Lights while taking into account the Roman Goddess Aurora who was known as the goddess of dawn, whereas the word Borealis came from a Greek god Boreas who was claimed to be the god of winter. Therefore, Aurora Borealis, derived from “Dawn Winter” or “Winter’s Dawn”.
For some, the winter can be a difficult time, the cold engulfing and the dark nights sombering, and for others the cold welcoming and giving a sense of home. But no matter, whether you look forwards to the longing warmth of the summer season, or if you are warmed in the shivering air, the Northern Lights remain a beauty and marvel to see.
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