The solar wind affects space weather.
The solar wind is radiation that is continuously emitted by the Sun. Made up mostly of protons , it also contains electrons and other components and propagates in all directions.
The release of these charged particles occurs in the solar corona , which is the outer layer of the star. In fact, the solar wind is considered to be the outermost area of this corona, which ends up being expelled into space by different energy processes that occur in other areas of the Sun.
It is important to note that the speed, temperature and density of the solar wind are not constant, but change over time. It should be noted that much of the solar wind is deflected by the magnetosphere (also called magnetosphere , with an accent on the second E), which is the magnetic field that develops around planet Earth .
Origin of the solar wind
The solar wind originates from the movement of the solar corona . It arises as a flow of particles with both a negative charge (electrons) and a positive charge (ions) that are expelled from this external layer of the star.
Due to its characteristics, the solar wind is considered a plasma . This means that it is an ionized gas that has a very high temperature.
Once it leaves the influence of the Sun's gravity, the solar wind moves through the solar system. In this way, it interacts with the magnetic fields of the different planets , as we already mentioned regarding the Earth and the magnetosphere.
The American Eugene Parker was the one who deduced the existence of the solar wind. This astrophysicist considered in the late 1950s that, due to its extremely high temperature, the solar corona must expand. Analyzing the tails of comets, Parker noticed that whether moving away from the sun or approaching it, they always point in the opposite direction. That is why he came to the conclusion of the existence of this solar plasma.
His contributions, in any case, were questioned. Only when space exploration advanced was it possible to confirm that the solar wind existed, although its characteristics are still being investigated. The Solar Orbiter mission, for example, managed to identify in 2024 small jets of plasma emerging from a coronal hole (an ozone of the solar atmosphere with an open magnetic field); According to specialists, these jets could contribute plasma to the solar wind.
Earth's magnetic shield deflects much of the solar wind.
Classification according to type
Scientists now know that not all solar wind travels at the same speed. The range can go from 300 to 700 kilometers per second , approximately.
The slow solar wind is one whose speed does not exceed 400 kilometers per second. Transcending that mark, we speak of fast solar wind .
Because each type of solar wind has its own characteristics, it is estimated that they have different origins. In fact, it is believed that the properties of the currents are related to the area of the solar corona from which they originate .
In open areas, the temperature is lower and magnetic field lines emerge that attach to the Sun at one end and extend into space at the other, favoring the release of the fast solar wind. On the other hand, in the closed sectors there are higher temperatures and the lines are anchored to the surface of the Sun at both ends, promoting the release of the slow solar wind.
The solar wind can threaten the operation of an artificial satellite.
Solar wind effects
As we already indicated, the magnetic field that surrounds the Earth works as a kind of shield since it manages to deflect a good part of the solar wind . However, there is a solar influence on the magnetosphere because the wind generates different effects on the environment surrounding our planet.
When the solar wind reaches the Earth's magnetic field, the particles in question are trapped and thus the so-called Van Allen belts arise. These particles, in this way, come together forming two stripes, each of them being a Van Allen belt.
Another consequence of the solar wind is the formation of the northern lights and the aurora australis . These phenomena appear with the impact of particles on the outermost atmospheric layers, in areas close to the geographic poles.
The solar wind is also responsible for every geomagnetic storm or solar storm . Its generation is linked to solar wind explosions caused by atmospheric phenomena such as coronal mass ejection (CME) . These geomagnetic storms can cause problems in radio communications, electrical networks and the operation of artificial satellites, for example.
Its ending
The path of the solar wind throughout the solar system gives rise to the heliosphere , a region that surrounds both the Sun and the planets.
Reaching the end of this area, a collision occurs between the solar wind and the opposing winds of the interstellar medium. Then a slowdown occurs abruptly and reaches the heliopause , which is the limit of the solar system and where the solar wind finally fades away. From that point interstellar space begins.