No parts of our universe are harder to explore than the interior of stars. With the support of the EU, asteroseismologists made use of oscillations observed on the surface of pulsating stars to study their internal structure.
The basic principles of asteroseismology are similar to those developed by Earth seismologists. Different oscillation modes – driven by turbulence or gravity – penetrate to different depths inside a star. The observed frequency spectrum, when carefully analysed, can reveal the stellar interior.
Further details: Peak bagging for asteroseismologists