Forty years of asteroseismology

Forty years ago, to within a day of the start of the present workshop, Aarhus University opened Symposium 123 of the International Astronomical Union, `Advances in helio- and asteroseismology'. At that time, helioseismology was a well-established field although the major helioseismic projects were still in the future, and oscillations were studied in a range of stars, including white dwarfs, while asteroseismology of solar-like stars was an eagerly-pursued dream. However, none of us dreaming at the time could have imagined the richness of the present asteroseismic investigations, from the deepest interiors of red-giant stars to the characterization of the evolution of the Galaxy and the ages of exoplanets. This has been the result of a tremendous evolution of the observational capabilities on the ground and in space, and the development, although still lacking behind, of our physical understanding of stellar interiors and oscillations. I shall provide a brief reminder of the status of asteroseismology forty years ago and a very few highlights of the evolution leading to its present stage.