I am a Dozent (University lecturer) at the Department of Astrophysics, University of Vienna. My research field is helio- and asteroseismology, which is the study of oscillations (vibrations) in the Sun and in distant stars. In the case of the Sun these oscillations are manifestations of sound waves which travel throughout the star. At certain frequencies these sound waves interfere constructively to form standing waves, also called acoustic modes, in a similar way what is happening in a musical instrument. From measuring the properties of these acoustic modes one can study many details of the physical processes that prevail in the deeper stellar layers, thereby allowing us to ''look'', for the first time, inside a star or, in other words, to make the star acoustically transparent. Other topics of my research include stellar convection modelling and the determination of stellar chemical abundances and ages.