Answer to Question #202917 in Astronomy | Astrophysics for Prachi

Question

Explain helioseismology. How does it help in understanding the internal structure of the Sun?

Answer 1

Helioseismology studies the oscillations of the Sun and helps to determine the properties of the structure and dynamics of the Sun. The oscillations considered by helioseismology are mostly caused by sound waves. The helioseismology utilizes essentially adiabatic oscillations, and it works with the parameters such as the pressure forces, the inertia density, the angular velocity (small value), the magnetic field, so studying the oscillations helps to reveal these parameters or their combinations. There also exists the global helioseismology and the local helioseismology (for sunspots or patches of solar surface).

Helioseismology allowed accurately measure the quadrupole moments of the Sun's gravitational potential. Also it revealed the existence of tachocline separating the a rigidly-rotating core and differentially-rotating envelope.