We explain what the northern lights are, how they are produced and where they can be seen. Also, the northern lights of Iceland, Canada and Norway.
What is the northern lights?
The polar lights (aurora polaris) It is an atmospheric phenomenon that occurs in certain regions of the planet, in the night sky of certain annual periods. It is characterized by the appearance of colored lights in elongated shapes over the firmament.
They occur near the poles and are called northern lights if they occur in the northern hemisphere. Those that occur in the southern hemisphere are called aurora australis. This phenomenon has intrigued humanity since time immemorial, and It was associated with snakes or dragons that crossed the sky or to particular gods.
Its scientific study began in the 17th and 18th centuries, until it was discovered that these are particles ejected by the Sun in its periodic combustions and that crash into the magnetosphere of our planet. In 1896, the Norwegian physicist Kristian Birkeland managed to reproduce them in the laboratory, greatly facilitating their understanding.
The polar auroras can be seen best between September and March (northern hemisphere) or between March and September (southern hemisphere). Its shape, colors and duration can vary enormously, oscillating between silhouettes close to the horizon and beams of light that cover the entire sky, tending to disappear as dawn approaches.
How are the northern lights produced?
Polar auroras occur when the magnetic layer surrounding our planet, known as magnetosphere, comes into contact with a diverse series of charged solar particles coming from some ejection of the star into space. These ejections are known as solar wind.
These particles travel at approximate speeds of 490 to 1000 kmps, covering the distance between our planet and the center of the Solar System in just two days. However, when they approach our atmosphere, the Earth's magnetic field repels them, and they flow around the planet like river water does in front of a stone, following the pattern of the magnetosphere.
A few particles are trapped in the magnetosphere charging the atoms of the upper layers of our atmosphere, which release excess energy in the form of visible light. It is a process similar to that which occurs inside neon tubes.
Where can you see the northern lights?
As we have said, polar auroras are usually seen in the vicinity of each Earth's pole, although it is possible to observe them for brief periods in other regions. This depends on the intensity of solar activity. The most common areas for observing auroras are:
- Northern hemisphere The coasts of Iceland are a frequent observation point from late August to April, as well as in Alaska, United States, specifically in the vicinity of Denali National Park. The same in the Canadian Northwest Territories, near the town of Yellowknife, or in the largest urban region in northern Norway, very close to the Arctic Circle, in Tromsǿ.
- Southern hemisphere The aurora australis in southern Tasmania, Australia and New Zealand are famously beautiful and can be seen all year round. However, the best location for this is Antarctica itself, the frozen continent, at least on its habitable coasts that face the southern American cone. In that sense, the last cities and regions of Argentina and Chile can also be points of eventual observation, such as the island of Ushuaia.
Northern Lights in Iceland
Iceland has regions close to the Arctic Circle that are ideal for observing auroras, especially between September and March, between 6:00 p.m. and 4:00 a.m., on the north coast of the Island. It should be taken into account that it is a sparsely populated region compared to the warmer south coast, where the capital is located. Reykjavik.
Northern Lights in Canada
The northern lights In Canada they can be best seen between October and March in the period of greatest darkness, although they are present throughout the year. The ideal territories to do so are in the northwest region and in the Yukon, especially in Whitehorse, Yellowknife, Tuktoyaktuk, Nunavut, Manitoba, Kuujjuaq or British Columbia and Alberta.
Northern Lights in Norway
In principle, You can see the auroras from all over the country although obviously the best regions are around the border with the Arctic Circle and the best time is between September and March. The Lofoten Islands and the coast to Cape Verde are good viewing points, as is Tromsǿ.
southern aurora
The aurora australis are just as beautiful as the northern lights, and do not have any type of distinction except that they are in the southern hemisphere. However, they are less famous because there are no populations near the South Pole, but the population of Antarctica is limited to the inhabitants of scientific and military bases.
References
- “Polar Aurora” on Wikipedia.
- “5 magical places to see the best northern and southern lights” in Infobae.
- “What is an aurora borealis?” in AstroAfición.
- “The polar aurora” at NASA.
- “Aurora (Atmospheric phenomenon)” in The Encyclopaedia Britannica.
