Solskælv – en kilde til viden om Solens indre

Abstract

The article gives an introduction to the study of the solar interior through observations of oscillations on the solar surface, here called 'sun quakes'. In analogy with seismic analyses of earthquakes this field of research is known as helioseismology. As described in the article the observed oscillations are caused by standing sound waves that propagate through the sun and which can be given a precise mathematical description that connects the observations to the properties of the solar interior. The observed oscillations have extremely small amplitudes, but as described techniques have developed allowing very precise studies of them. The article was published at a time where ESA and NASA collaborated on the development of the space mission SOHO for solar observations, and it describes new instruments included on SOHO for helioseismic observations. SOHO was launched in December 1995 and has since then given invaluable data for helioseismic studies of the solar interior.