Solar storm 2022: what consequences of an eruption of the sun?

SOLAR STORM. On the night of Monday July 18 to Tuesday July 19, a solar storm hit our planet Earth, disrupting telecommunications networks. Learn all about this rash like no other.

[Mise à jour le 19 juillet à 19h20] This night from July 18 to 19, 2022, “a massive solar flare that had escaped from the Sun on July 14” affected our planet Earth, according to NASA. Formed by too much energy on the surface of the Sun, a solar storm shoots high-speed particles out into space, between 300 and 1,000 kilometers per second, which can strike the upper atmosphere of our planet Earth and interfere with its magnetic field.

Space weather physicist Dr Tamitha Skov described the phenomenon of this solar plasma hurled into space on Twitter: “The long snake-like filament streaked away from the Sun in a breathtaking ballet. The magnetic orientation of this storm solar directed towards Earth is going to be difficult to predict”. The doctor, however, gave forecasts on the intensity of the solar event, which she classified as “moderate”: “Level G2 (possibly G3) conditions can occur if the magnetic field of this storm is oriented towards South !”

A solar flare causes the aurora borealis but, when strong enough and directed towards the Earth, can also distort the ionosphere of our planet, that is “the zone of the upper atmosphere characterized by the presence of charged particles (electrons and ions ), formed by photo-ionization under the effect of solar radiation”.

This deformation often causes disruption of communication systems (radio waves and GPS) and high altitude electrical distribution networks. The equatorial and polar regions are the most affected by its consequences. It should be noted that solar storms are relatively frequent phenomena, and that they rarely cause extreme consequences. However, a peak in solar flares is expected in the summer of 2025.

Rest assured, solar flares are quite common and only last from a few minutes to several hours. But in the case of a super eruption, the consequences would be quite different. It could then grill the circuits of the satellites and destroy the ozone layer which filters ultraviolet rays, deadly to all human life…

What is the Sun?

Formed 4.6 billion years ago, the Sun is the star of the solar system. Located 150 million kilometers from Earth, it is the closest star to our planet. Eight other planets orbit around it within the solar system.

The Sun is a gaseous sphere, made up of 6 successive layers. The core, the radiative zone and the convection zone are the inner layers. The photosphere is the layer on the surface of the Sun that emits light radiation. Above it is the Sun’s atmosphere, formed by two other layers, the chromosphere and the corona, the latter being the outermost layer.

The Sun is made up mainly of hydrogen and helium, two gases involved in thermonuclear reactions. It is these reactions that produce the light that the Sun emits.

What is the temperature of the Sun?

The temperature of the Sun is not the same in all the layers of its structure. Thus, at the level of the core of the Sun, the hottest part, the temperature reaches more than 15 million degrees. On its surface, it is 5,570°C, then increases in the Sun’s atmosphere, reaching more than 5 million degrees. This extreme temperature is maintained by nuclear fusion reactions that occur between hydrogen atoms.

The temperature of the Sun is therefore maximum in its core, decreases at the level of its surface and again increases considerably in the outermost part of its atmosphere. Usually, as you move away from a heat source, the temperature drops. This increase in heat at the level of the star’s atmosphere is therefore one of the great mysteries of contemporary physics.

What is the composition of the Sun?

The Sun is made up of 91% hydrogen, 8.9% helium and 0.1% heavier elements such as carbon and nitrogen. Hydrogen and helium are therefore the main constituents of the Sun. These gases are present in the plasma state, the state obtained by heating a gas to a very high temperature.

Hydrogen is the fuel of the Sun, causing the nuclear fusion reactions that maintain the temperature of our star. Indeed, under the effect of the pressure and the temperature which reign in the heart of the Sun, the hydrogen atoms fuse, forming helium atoms and producing in the process a large quantity of energy in the form of heat and light.

What is the origin of the sun?

The Sun was formed 4.6 billion years ago from a cloud of gas and dust along with the entire solar system. The gases and dust accreted, making the whole thing more and more dense. Little by little, a nucleus was formed. The heavier the latter became, the more dust and gas it attracted under a snowball effect. This process thus created a star mainly composed of hydrogen: the Sun.

This star is very dense. The gases are therefore very compressed, which increases the temperature. Under this extreme pressure and heat, the hydrogen atoms fuse together, forming helium atoms. This reaction has the effect of releasing energy, which crosses the different layers of the Sun and radiates in the form of light.

The Sun will not shine forever. Indeed, within a billion years, it will have consumed a large part of the hydrogen which it uses as fuel to carry out its thermonuclear reactions. At that time, its core will consist of helium, the product of these reactions. Having become very dense, the core will collapse on itself, generating heat, which will cause the expansion of the Sun. The latter will thus transform into a red giant which could encompass MercuryVenus and even the Earth.

Gradually, the helium and hydrogen that make up the Sun will be consumed by its thermonuclear reactions and the star will eventually retract under the effect of its own mass. It will then turn into a white dwarf. At this point, the Sun will still shine because of the heat it will continue to emit, but its luminosity will be very low. Slowly it will cool down and eventually become a black dwarf, too cold to generate light.