Are the days getting shorter? And what is the magic of polar winter? Let go out at night and look up to the sky to see the Northern Lights – one of the most beautiful natural spectacles. . This fantastical display lights up the Arctic, sub-Arctic regions and even memories.
The Northern Lights light up the night skies in some of the northern regions of the world. Their silent beauty almost makes us forget their origins and causes. What is an aurora borealis and how is it formed? Where are the best places in the world to see them, and when is the best time of year? In winter, let’s not let our dreams of travelling fall asleep, and let’s go under the stars.
What is an aurora borealis?
The beliefs of the Far North (Eskimo, Celtic, Amerindian…), stemming from myths and legends, have attributed these strange celestial phenomena to the souls of departed ancestors. Some associated them with bad omens, others attributed supernatural powers to these apparitions. Modern day myths exist too – the Japanese believe that babies conceived under the northern lights will become intellectuals.
But science has since contradicted all these beliefs 🙂
An aurora borealis is a natural light phenomenon resulting from a solar flare, which spreads across the sky. The surface of the sun emits particles (protons, electrons and ions) at supersonic speed; this emission or solar flare is called the solar wind. At the same time, the Earth’s magnetic field creates a natural shield that protects the Earth from the incoming solar particles.
At the poles, the magnetic field that protects our planet is weakened, and the charged solar particles are guided towards these poles, which then exert a powerful magnet effect. This is why the aurora borealis occurs there, and why the term ‘aurora borealis’ is used generically: aurora borealis in the northern hemisphere, aurora australis in the southern hemisphere.
In the upper atmosphere (upper atmosphere or ionosphere), energetically charged solar particles collide with atoms or gases in the Earth’s upper atmosphere (mainly oxygen, hydrogen and nitrogen). During this collision, the solar particles ignite, generating luminous flashes that leave coloured glows, trails or clouds in the clear sky. Some of them appear simultaneously. And as they move, these nebulous veils seem to dance across the sky.
What are the conditions to observe an aurora borealis?
A whole series of meteorological and atmospheric conditions must be met for the aurora borealis to form; the aurora borealis is therefore the result of a kind of alignment of the stars. The aurora borealis occurs in winter, in the northern hemisphere. Of course, you have to wait until nightfall.
The spectacle is observed in the so-called “auroral” zone, located between 60 and 75°C latitude. The night must be dark, preferably long, and the sky must be free of light pollution, which means that you must stay away from cities. Also, a moon that is too bright can interfere with the visibility of an aurora borealis, so the lunar calendar should be watched, avoiding full moon nights.
In order to be seen with the naked eye, the aurora borealis must reach a minimum intensity. This means that a certain particle density is required. In Iceland, for example, the northern lights occur all year round, but are only really visible from a certain intensity, between September and April.
If the most active aurora zone is near the North Pole, in a geomagnetic storm, the possible observation area is larger and their visibility better. They are then visible from lower latitudes, especially from the Baltic countries (Estonia, Latvia and Lithuania).
Why do the aurora change colour?
The colour of the aurora depends on two factors: the nature of the colliding elements (atoms and molecules, and ions), and the altitude at which the collision occurs. As for the altitude, most auroras occur between 90 and 1 000 km above sea level.
While the aurora borealis is most often a fluorescent green colour, it can also be purple or shades of blue, yellow, orange or reddish. Green, red and blue are the three colours that the human eye perceives best. But in the end, all the colours of the colour wheel are observable. In some clouds, gradations from one shade to another can be detected.
Summarise: Green, the most common colour, indicates that particles have collided with oxygen molecules between 100 and 300 km altitude; pink and dark red indicate the presence of nitrogen molecules, and a collision at about 100 km height; Red indicates the existence of oxygen atoms and a collision beyond 250 km, generally between 300 and 400 km altitude; blue and purple indicate the presence of nitrogen, hydrogen and helium molecules, below 100 km (blue) and beyond 100 km altitude (purple). The latter two colours, blue and purple, are of course more difficult to see with the naked eye against a night sky.
When is the best time to observe the Northern Lights?
The best time to see the Northern Lights is between late August or September and March-April. However, the best time to see them is during the winter months, between 21 September and 21 March. The advantage of this winter period is that the nights are very long.
The end of winter, from February to April, is another good time for other reasons: the nights are still long, and the skies in the far north are often clearer than in the middle of winter. In Finnish Lapland, conditions are even best in April. The optimum time is between 6-8pm and midnight-1am, and at the peak of auroral activity, from 6pm to 3am.
Where are the best places to see the Northern Lights?
The northern lights can be seen in the far north. With this in mind, it is important to choose your destination carefully, but the possibilities are vast. Visit Scandinavia, a favourite destination for aurora hunters, from Norway to Finland via Sweden, as well as northern Russia. The more intense the auroral activity, the lower the latitude of the aurora visibility zone.
In Norway, we station ourselves from the Lofoten Islands to the North Cape, via Tromsø and the Svalbard archipelago. In Tromsø, the Prestvannet lake is a popular observation spot, as well as the surrounding islands of Kvaløya and Sommarøy. Finnmark in Norwegian Lapland is another popular spot.
In Sweden, the forests of Swedish Lapland are the focus. The Aurora Sky Station, at the tip of Abisko National Park, is said to be the best observation spot in Sweden. Other places of interest include the mining town of Kiruna and Jukkasjärvi.
In Finland, the hunt for the Northern Lights takes place in Lapland. There, they appear above fir forests and lakes frozen in the ice, in the Ivalo region and in the Urho Kekkonen National Park.
The Northern Lights can also be seen under the Celtic skies of Scotland, in the Highlands and far north, the Shetland and Orkney Islands, and as far north as the Isles of Lewis and Harris, the Isle of Skye and the Cairngorms.
Further north, they can be seen from the Faroe Islands, where the best time to see them is in the depths of winter, between November and February.
Iceland is also a great place to see the Northern Lights. From October to March, they can be seen in the Reykjavík area, Landmannalaugar hot springs, over volcanoes and glaciers and over Lake Mývatn….
At these same latitudes, aurora hunters can change their longitude and cross the Atlantic to North America. Head for Canada, more precisely the Canadian Great North: Alberta (Wood Buffalo National Park), Saskatchewan, the Yukon (Whitehorse region), the Northwest Territories (Yellowknife region) and Nunavut, and to a lesser extent, northern Quebec. The United States territory also benefits from this magical spectacle from the boreal forests of Alaska (Fairbanks, Anchorage, Denali National Park and Preserve).
Those who are not so keen on travelling to the northernmost reaches of the earth, to Greenland. They will set up their tripod in the regions of the capital Nuuk, Kangerlussuaq, Ilulissat (west coast) and Tasiilaq (east coast).
Tips for viewing the Northern Lights
Destinations offer a variety of viewing options: excursions, safaris, or all-inclusive packages with viewing tours, accommodation (in cabins, glass igloos, ice hotels or trapper’s huts), and other winter activities (dog sledding, snowshoeing, cross-country skiing, saunas, etc.).
Several forecasting sites and applications monitor auroral activity in real time and provide predictions. These tools announce, identify and locate the aurora borealis, and evaluate the probability of seeing them depending on the area, a few hours or even a few days in advance.
However, there is no question of planning your trip, or even your itinerary, according to these forecasts, because you must bear in mind that the appearance of the northern phenomenon is never a guarantee. It remains a privilege and a miracle. Seeing the Northern Lights is not an end in itself, but rather the crowning glory of the trip.
The northern lights the only absolute, must-see bucket list travel item that exists in the sky. And the best advice for all northern lights hunters, from all longitudes: be patient!