What the Sun’s eruptions are made of and the cause: the study

Discovery is useful for space weather forecasting. Magnetic tangles on the surface of the Sun produce the eruptions of particles and ionized gas.

The active regions from which violent eruptions of particles and ionized gas capable of affecting even the Earth can start are produced by the emergence of magnetic tangles on the surface of the Sun. To prove it are the data collected by the Solar Dynamic Observatory (Sdo) satellite of NASA. The study of an international group led by David MacTaggart of the University of Glasgow, in which participated among others Paolo Romano and Salvatore Guglielmino of the National Institute of Astrophysics (Inaf) in Catania, were published in Nature Communications.

What are the origins of solar flares

The most violent eruptions in the Solar System originate in the active regions of the Sun, areas where there are intense magnetic fields that can be very complex and tangled. Solar flares (flare) and coronal mass ejections (Cme) are phenomena that release large amounts of energy, particles, and ionized gas and can have important effects on Earth's environment as well. Knowing the properties of the twisted lines of the solar magnetic field is essential to understand the mechanism of triggering of solar flares. One question that remains open in science is whether the twist, called a twist, of magnetic fields emerges on the solar surface by rising with its active region or is instead created later in the solar atmosphere.

The International Solar Flares Group study

To answer the question, the researchers focused on the emergence of an active region, Noaa 11318, which they had already studied in 2014. Comparing observations with numerical simulations, they found that active regions arise from the emergence of already-twisted magnetic flux tubes. "For the first time, we obtained a direct measurement of the magnetic field topology of an active region observed during its emergence in the photosphere," Guglielmino explained. "The twist process is essential for the triggering of energy release phenomena in the solar atmosphere - he added - so having the ability to determine from the earliest stages of the emergence of an active region its topology, more or less twisted, will allow us to better understand its eruptive potential. This will increase our ability to make more accurate predictions also in the field of space weather".

In the meantime, another study has identified that the Sun is waking up after a period of quiet during its 11-year cycle.

Stefania Bernardini