THE Northern Lights is an optical phenomenon that occurs in the extreme north of the Earth, forming, together with the Austral Aurora (which occurs in the southern hemisphere), the two types of polar auroras that happen on the planet. Its occurrence is directly associated with solar winds and Earth's magnetic field.
The aurora borealis occurs whenever a large amount of electrons from the solar winds interacts with elements of the Earth's atmosphere at great speed. This interaction causes a strong shock between the molecules, causing a luminous photon to be produced, whose color depends on the wavelength generated by the particles involved in this process.
Furthermore, polar auroras only occur in areas of high latitude due to the strength of the Earth's magnetic field. What happens is that the electron-laden solar winds move at about 1.6 million km/h and when they reach the our planet, end up being easily guided by the magnetic force generated by the Earth's core, going to the areas polar. At that moment, part of the solar wind is captured by the ionosphere – the upper layer of the atmosphere –, being conducted and accelerated in a kind of “tunnel magnetic" that is formed, which causes the generation of light effects when there is an interaction of this electrically charged solar wind with the gases atmospheric.
There are aurora borealis of different colors, which depend on the type of gas or molecule that participated in this interaction with electrons from the solar winds. Oxygen, depending on the altitude at which the phenomenon occurs, can generate green or red aurora borealis; nitrogen, also depending on the altitude, can generate blue, purple or violet auroras.
The aurora borealis phenomenon is usually a major tourist attraction, being a natural event sought after by thousands of people every year. The place in the world where its occurrence is most frequent is the city of Lapland, Finland, which usually receives a large number of tourists in September and October and also in February and March, periods of the year when this true spectacle is most likely Natural.
By Me. Rodolfo Alves Pena
Source: Brazil School - https://brasilescola.uol.com.br/geografia/aurora-boreal.htm