The Northern Lights
What is the Aurora?
The temperature in the Sun’s core is huge. At this temperature, a nuclear fusion reaction of hydrogen occurs. As a result, electrically charged particles are thrown out from the Sun’s atmosphere and they escape into space. At some point, they reach Earth and they interact with Earth’s magnetic field (the magnetosphere), creating a so-called disturbance in the magnetosphere. These high energy solar wind charged particles begin then colliding with the gases that make up Earth’s atmosphere (mostly oxygen and nitrogen). These collisions determine the emission of visible light. It is this visible light what we call the Aurora Borealis or the Northern Lights.
The colours of the Aurora
The colours of the Northern Lights are due to the nature and the altitude of the atmosphere’s atoms which are being hit by the high energy particles from the Sun. Each chemical element, emits visible light of a certain colour. At the altitude where Auroras mostly occur, the atmosphere is mostly composed of oxygen, which emits green light in a few seconds. This is the reason why Auroras are mostly green.
You can see other colours in Auroral displays, and should you wish to understand why all these colors occur, why not enroll in my online course, where you will learn everything about the Northern Lights?
Forecasting the Aurora
Kp index
The collisions between the charged particles of the solar wind and the air molecules in the atmosphere are not equal, and they have different levels of strength, which determines how far south the Auroras could theoretically be seen. This strength is quantified by the Kp index, or “planetary index”. Kp ranges from 0 (minimum activity) to 9 (maximum activity). The bigger the Kp, the more south Auroras can be seen. In Varanger and Vadsø, as like on any place on the Auroral Oval at Kp = 0, the Kp needed for seeing the Northern Lights is 0. That makes Varanger and Vadsø one of the best places on Earth to see them, even if there’s a minimum activity (during a solar minimum year for example)!
The Solar Wind
This Kp index is not the only (or not even the most important) factor to take into account when trying to see the Northern Lights. It is just an indicator of Auroral activity. Theoretical Auroral activity that is.
Other factors are also important to consider when hunting the Northern Lights, EVEN on the Kp = 0 Auroral Oval. Among these, of importance are the solar wind speed, density and Bz component of the solar wind’s magnetic field (called interplanetary magnetic field, IMF). The latter, Bz, needs to have a negative value for the collisions to create more dramatic displays of the Aurora.
Hemispheric Power
Another factor to take into account for estimating the probability of visible Auroras is the hemispheric power, which quantifies a globally calculated total energy. It ranges between 5 – 150 GW. For a value of 20 GW or less, it’s possible to estimate that there will be no or very little visible Auroras, and this only in the Kp = 0 zone. A value more than 50 GW means that the activity is increased, and the chances of seeing the Northern Lights are very big on a wider area. Higher values correspond to geomagnetic storms, thus to very intense Auroras, visible at very southern latitudes.
During your stay in Vadsø with me, we will experience together a Northern Lights Hunt and the Aurora Workshop. As an experienced guide, I will share with you all the knowledge you need to become a Northern Lights hunter yourself! Or, from the comfort of your home at any time, you can enroll in my online course.
Weather and the Northern Lights
Clouds
Perhaps the most important thing to take into account when hunting the Northern Lights, is the weather. More exactly the cloud coverage. Because clouds occur at much lower altitudes than the Auroral displays, they will obstruct the view of the dancing Northern Lights. It is very important to take this factor into account. An experienced Northern Lights hunter can estimate where these elusive Lights could actually be seen through cloud clearings, during a cloudy night. I studied meteorology at Harvard, and I have deep knowledge of the region and of interpreting space weather. This allows me to significantly increase the chances of seeing the Northern Lights during a hunt – though, in the end, nothing can ever be guaranteed.
Temperature
Northern Lights do not depend on temperature. They even happen during the summertime when it’s warmer in Vadsø. It’s just not possible to see them because of the continuous light. (Although you can hear the Aurora!) However, it is true that colder temperatures in winter help the sky be clearer of clouds and the chances to have a clear sky are better.
What’s the best place on Earth to see the Northern Lights?
The Geographic Localisation of the Auroral Oval
The region where Auroras mostly occur are oval regions surrounding the magnetic poles (which are close, but not the same as the geographical North and South Poles). On these oval regions, a minimum solar activity is needed for Northern Lights to appear. This is what is known as the Kp = 0 Auroral Oval. On the Kp = 0 Auroral Oval, not only the chance to see the Northern Lights is at its maximum, but they are also seen overhead.
Vadsø and the whole region of Varanger is placed right in the middle of this Kp = 0 Auroral Oval, thus it is one of the best places on Earth to choose for seeing the Northern Lights.
The further North or South from the Auroral Oval you are, the lower on the horizon the aurora will be, till some point where the Northern Lights cannot be seen anymore. This place is scientifically known as the “Auroral view line”. So, going too far North is not the solution to see the magical Aurora.
Light pollution
Another very important point to take into account when choosing a Northern Lights destination, is the light pollution. Especially when the Lights are weaker, light pollution can diminish (or even cancel) the actual sighting of the Aurora. Thus, it is important to hunt the lights away from strong light sources (especially far away from big cities).
Needless to say that nighttime is the best time to see the lights display. Polar nights are especially of interest, as the rare and weak “daytime auroras” can also be seen. These are the Auroras that form on the “day-side” part of the Earth. These Auroras however, can only be seen in regions where it is dark during the day – thus, in regions where the Polar Night occurs.
Typically, whenever people speak about the Northern Lights or the Aurora, they are talking about the “nighttime auroras” – which are the Auroras that form on Earth’s “night-side” and which can be seen during the night.
Vadsø and Varanger are, yet again, ideal from this point of view as well, as there are no big cities here and no light and no air pollution.
How to photograph the Northern Lights?
It is not as easy as it may seem at first! But, by choosing the correct camera settings, things start to ease up!
As a general rule, try to use a long exposure time (at least 1-2 seconds during strong Aurorae or longer during weaker displays) and a countdown timer or remote shutter.
Pay also attention the ISO sensitivity (not too big, as your pictures become too grainy) and also, use a tripod. The tripod is of utmost importance if you would like a clear photo of the magnificent Lights!
The Hunt the Aurora activity at Aurora Labs already includes detailed explanations to every group member on how to photograph the Aurora, so that everyone in the group can learn to capture one of the most beautiful natural phenomena that exist in our World.
Hunting the Aurora
Last but not least, when trying to see the Aurora, it is important to not have extremely high expectations. The Northern Lights are not called elusive for nothing. Sometimes they just don’t show up and it is perfectly normal.
However, remember that here in Vadsø, you’re under the right sky to experience them. You can even maximize your chances of viewing them when you know where and when to look! And I am pretty experienced in choosing the best place and time! Not only your chances of sighting the Northern Lights are hugely increased by the mobile nature of the tour, but I choose the route in function of the weather and auroral signs (even during a cloudy sky!).
Most importantly, remember to have fun while hunting the Aurora! Hunting the Northern Lights, even if you don’t finally see them, is one of the most beautiful experiences that you can have in the Arctic!
…And if, in the end, the Aurora simply decides not to appear, why not take the opportunity to learn more about it during my Aurora Workshop spread on multiple days during your stay in Vadsø – or from the comfort of your own home, by enrolling in my online course entirely dedicated to the Northern Lights?