Rationale

Seismic study of pulsating stars in the era of the high-precision data is one of the most rapidly developing branches of astrophysics. Owing to measurements obtained by space missions such as Kepler, CoRoT, and MOST, and to high-resolution, high-signal-to-noise spectroscopy, the numbers of known oscillation frequencies of distant stars have increased by orders of magnitude, and new classes of pulsators have become available for seismic study.

The new high-quality data have strongly advanced the study of small-amplitude solar-like oscillators in the main sequence and giant stages. Important synergies with extrasolar planet studies have emerged because they face the same observational difficulties. Moreover, if an exoplanet's parent star oscillates then valuable information on stellar parameters and interior can be derived using seismic methods.

Regular frequency patterns observed in solar-like oscillators and pulsating white dwarf stars facilitate identification of stellar oscillation modes. This identification is more difficult for pulsators lacking regular patterns in their oscillation spectra, as already learnt from space missions, but also from multi-site campaigns (WET, DSN, STEPHI etc.) and massive surveys (OGLE, ASAS).

How can such rich, but irregular oscillation spectra be made best use of? How strongly do modes with high spherical degree complicate mode identification? What new methods can be applied to understand and model rich but irregular oscillation spectra? Can current model atmospheres reproduce the observed flux and radial velocity changes? Where are the limits of the application of asteroseismology and the physics that can be extracted? Finally, how will all these these data help to solve the problems and uncertainties in stellar physics? For example, most of the theoretically unstable modes are not detected in observations. Are we still missing something in the opacity data? The other vital problem is the efficiency of convection and its interaction with pulsation. Moreover, the role of rotation and element mixing in pulsation excitation and stellar evolution is still rather poorly known.

This conference intends to discuss what are the missing physics in stellar structure and evolution theory and how these may be retrieved from the analysis of stellar oscillations. Moreover, we would like to point out the synergies between helio- and asteroseismology and how the experience and methods of helioseismology can be used to advance asteroseismology efficiently.

At the time of the meeting, first results from two new asteroseismic projects will be available. The BRITE mission, a Canadian-Austrian-Polish project of six nanosatellites for asteroseismology, is under realization now. It will be the first to obtain multicolour space photometry of pulsating stars for mode identification, holding the promise of a breakthrough in the study of hot main sequence pulsators. On the other hand, the prototype telescope of the worldwide high-precision spectroscopy SONG network will have delivered first data, pushing the study of solar-like and classical pulsators to new limits. Spectroscopy and multicolour photometry work hand in hand to understand all kinds of stellar variability.

The symposium will be the 21st in a sequence of pulsation meetings held biennially since 1971. It will be also an opportunity to honour Wojtek Dziembowski, one of the world's leaders in the study of solar and stellar pulsation.