The level of magnetic activity and frequency of appearance of sunspots on the surface of the sun were associated with how much iron and some other heavy elements are contained in the corona, the upper layer of the atmosphere of the luminary.
“Previously, scientists believed that the chemical composition of the atmosphere of stars depended on those physical properties that never actually change, such as the speed of rotation or the force of gravity on the surface.” We found that the composition of the crown actually changes constantly, Depends on the level of magnetic activity and how the corona is heated, “says David Brooks of George Mason University in the United States.
The sun is a ball of red-hot plasma, the upper layers of which are constantly “mixed”, which in combination with the high electrical conductivity of the plasma creates a strong magnetic field. Lines of the magnetic field often go beyond the denser layers of the Sun, which leads to the appearance of spots and powerful coronal emissions, potentially capable of destroying civilization and all life on Earth.
The high temperature of the crown, the uppermost layer of the solar atmosphere, is still a mystery to astrophysicists. The underlying layers of the sun, the chromosphere and the photosphere, are heated to a temperature of about six thousand degrees Kelvin. In the boundary layer between the corona and the photosphere several kilometers thick, this temperature sharply increases by a factor of hundreds, which today is associated with not yet completely clear processes inside the sunspots and magnetic “tubes” on the surface of the luminary.
Brooks and his colleagues uncovered an unusual relationship between the appearance of these spots and the behavior of the Sun’s crown, trying to understand why the chemical composition of the atmosphere of the star differs sharply from how the upper layer of its interior is arranged.
Analyzing the data that the SDO probe collected during the first four years from its induction into orbit, the scientists noticed something unusual – the fractions of iron, magnesium and silicon ions strangely changed over time. This discovery was a surprise to Brooks and his colleagues, as they did not expect that they would see even small shifts in their concentrations.
Comparing these fluctuations with other cycles of solar activity, astronomers were surprised to find that the increase and decrease in the number of ions of astronomical “metals” were related to how often spots appeared on the Sun and how often flashes appeared on its surface. In other words, the higher the magnetic activity in the bowels of the Sun, the more iron, magnesium and other metals contained in the corona.
Why this happens, the scientists do not know yet, but the existence of such a connection suggests that processes in the deep layers of the Sun can play a very important role in the warming up of the crown and that they can be studied by observing changes in the concentration of “metals” on the surface Of the luminary.
More interesting, this discovery looks from the point of view that it allows us to study the activity cycles inherent in distant stars, which we can observe with the help of Hubble and other telescopes. Guided by this idea, Brooks and his colleagues analyzed the spectrum of several stars, which astronomers followed for several years, but they were expected to fail – they could not find such interconnections.
According to the researchers themselves, they obtained similar results because such observations were not carried out long enough, and that this dependence rather exists than is absent in the behavior of stars far from us. In the future, as they hope, longer cycles of observations will be conducted to help us understand whether the activity of other stars varies cyclically or only in the Sun.