In a paper published in prestigious scientific journal “Astronomy and Astrophysics”, an international team with the leadership of the scientists from Ilia State University discovered short cycles on a solar-type star. Using the short cycles, the magnetic field strength in the stellar interior was estimated for the first time. This discovery will help the scientist to study the past and future of our Sun.
The Sun is our nearest star, which has a significant impact on the living conditions of our planet. Therefore, it is crucial to know how the evolution of the Sun and its magnetic field will proceed in the future. This can be ascertained by observing early and late solar-type stars.
The existence of cycles with periods of 150-180 days in solar activity has been known for almost 30 years and are characterized by many enigmatic features. The most plausible explanation for these cycles is the magnetic Rossby waves in the solar interior. Similar processes may exist in the Sun-like stars. “Using the observations from NASA space mission Kepler, we have discovered short-term cycles similar to the Sun on one of the stars. Using these cycles and the properties of magnetic Rossby waves, we estimated the magnetic field in the stellar interior for the first time. Interestingly, the stellar magnetic field turned out to be 3 times stronger than the solar field, while the stellar rotation is three times faster than the solar rotation. This shows that the stellar magnetic field is inversely proportional to the rotation period, “said Eka Gurgenashvili, leading author of the study, a doctoral student at Ilia and Gottingen (Germany) universities, and a researcher at the Abastumani Astrophysical Observatory. “Currently, research is ongoing, and we are studying the light curves of other stars to detect similar cycles, which will allow us to estimate the magnetic field of other stars. “Our goal is to predict the future magnetic activity of the Sun.”
Future research will also concern a detailed study the data of NASA’s new mission TESS data.
The research was conducted within the framework of the Lehman-Haupt International Doctoral Program.
Paper:
E. Gurgenashvili, T. V. Zaqarashvili, V. Kukhianidze, A. Reiners, A. F. Lanza and T. Reinhold, Rieger-type cycles on solar-like star KIC 2852336, Astronomy & Astrophysics, 10.1051/0004-6361/202142696
Contact:
Eka Gurgenashvili
PhD Student at Ilia State and Goettingen Universities.
Researcher at Abastumani Astrophysical Observatory.
eka.gurgenashvili.1@iliauni.edu.ge
