Polar Aurora: the beauty of nature

It is caused by the interaction of charged particles of protons and electrons coming from the solar wind with the earth's ionosphere

by Lorenzo Ciotti
Polar Aurora: the beauty of nature

Polar Aurora is an optical phenomenon of the Earth's atmosphere, characterized mainly by light bands of a wide range of shapes and colors rapidly changing over time and space, typically red-green-blue, called auroral arcs, caused by the interaction of charged particles of protons and electrons coming from the solar wind with the earth's ionosphere.

These particles excite the atoms of the atmosphere which, when de-energized, emit light of various wavelengths. It is called the Northern or Southern Lights depending on whether it occurs in the Northern or Southern Hemisphere respectively.

Due to the geometry of the Earth's magnetic field, the auroras are visible in two narrow bands around the magnetic poles of the Earth, which are very close to each other, but give the Auroras around them the name of Auroral Ovals.

The auroras visible to the naked eye are produced by electrons, while those of protons can only be observed with the aid of special instruments, both from the ground and from space, however you must be in the Norwegian ray if you want to observe it from this position.

Often the polar aurora is also visible in areas less close to the poles, such as Scotland, or many areas of the Scandinavian peninsula, but this does not mean that you can see it, in its entirety, you have to go to the source of it, to observe its colorful colors, which change depending on how far away you are.

More intense and frequent auroras occur only during periods of intense and lava solar activity, which happens in periods in which interplanetary magnetic fields can present considerable variations in intensity and direction.

In scientific centers around the world, the instrumentation underwent strong and inexplicable variations and spurious currents formed in the telegraph lines in 1859, specifically on August 28th. The following day, the English astronomer Richard Christopher Carrington noticed a group of sunspots of unusually large size, from which a flash of whitish light emanated, which after a few hours produced a second wave of auroras of great intensity.

With the Great Aurora of 1859, the models of explanation of the phenomena of solar activity evolved rapidly and the ancient hypotheses of flashes at high altitudes, or of light reflected from icebergs were replaced by those more related to solar events and perturbation.

Storms of this intensity are estimated to occur every 500 years. The last event of half the intensity of 1859 occurred in 1960 causing radio outages across the planet. Experts believe that the costs of a possible super storm could be comparable to those of a major earthquake, should the appropriate countermeasures be lacking, such as postponing some delicate activities carried out by satellites, moving air routes, identifying vulnerable elements in advance.

networks. The solar magnetic activity, and therefore also the formation of sunspots, varies cyclically every eleven years. The new cycle began in January 2008, so it is reasonable to expect an increase in activity over the next few years.

Over the past eleven years, scientists have detected about 21,000 flares and 13,000 clouds of plasma escaping from the solar surface.