The orbiting solar probe reveals the secrets of the solar wind

Wind is a current of air. It is formed when air expands under the influence of heat and then rises into the airAtmosphereAtmosphere The Earth thus exerts pressure on the air surrounding it. But what scientists call the solar wind corresponds to a completely different phenomenon. A type of stream of electrically charged particles emitted by the Sun. the flow, Astronomy scientistsAstronomy scientists Know it, a variable like ours windswinds. Its speed, density, or composition – in ElectronsElectrons And in ProtonsProtons Above all – it can change over time and depends on the sun zone it comes from.

What astronomers know less is where exactly this is Solar windSolar wind. More precisely, where does the so-called slow solar wind come from? Because researchers distinguish two types. The so-called rapid consists of particles moving at a speed of more than 500 kilometers per second. It originates from coronal holes, which are areas where there are lines magnetic fieldmagnetic field It is only connected to the sun at one end. The slow solar wind does not exceed a speed of 500 kilometers per second. Astronomers assume that it is linked to the active areas in our bodies a stara star. These are the areas that SunspotsSunspots Where magnetic fields are twisted and concentrated. Also disconnect and reconnect sometimes. But the details of the process are still far from known.

The importance of understanding the mechanism behind the solar wind

However, it is important to better understand where the solar wind forms. Because he is on his trip in our country Solar systemSolar systemIt interacts with celestial bodies – such as Earth – and with spacecraft. The solar wind is thus as much a cause of the magnificent northern lights that can light up our skies as it is the cause of the damage it can do to our electrical systems, sensors, or satellites.

the mission Solar orbitSolar orbit, which launched in 2020, has exactly that goal. Confirmation of the origin of the solar wind. And in the magazine Nature astronomyData collected during the Sun's first very close pass, at the beginning of March 2022, have just delivered their verdict, researchers report. The Solar Orbiter mission was then only about 75 million kilometers from the star (half the distance between Earth and the Sun).

Solar Orbiter, tools for tracking the solar wind

Solar Orbiter's main advantage in carrying out its mission is its ability to measure the solar wind and the surrounding magnetic field and record images of our Sun and other data from a distance. By combining these two sets of data together, astronomers can position the mission so that it picks up solar wind coming from specific regions of the sun. These are the coronal hole and the active zone.

Thus, researchers were able to observe how the speed of the solar wind changes – from fast to slow or vice versa – as well as its composition, temperature and density when recorded over an “other” region or region. Suffice it to confirm that coronal holes, as expected, expel streams of particles that shoot through space at an insane speed of more than 1.8 million kilometers per hour. Sunspot clusters emit a slower type of solar wind. As if the solar wind carries a sign “Fingerprints” It is transmitted through different areas of its source.