Transcript: The Sun oscillates or vibrates at many frequencies like a bell. Solar oscillations can be used to study the interior of the Sun just as geologists use seismic waves to study the Earth’s interior. In fact, apart from neutrinos this is the only way to reliably map out conditions inside the Sun. The best known solar oscillation has a five minute period and corresponds to cells near the surface moving up and down by distances of about ten kilometers. This represents the kind of boiling of the solar surface. It can also be measured by the Doppler Effect in the gas motions and the light emitted by cells near the surface. The Sun has highly complex behavior, and solar seismology is a rich field. Hundreds of modes of oscillation have been observed in the Sun, and recently the principles of seismology have begun to be applied to other stars as well.