The IACOB project in context

The last 2 decades of the 20th century witnessed enormous advance in the field of massive stars thanks to increasing computer power and the development of sophisticated stellar atmosphere codes. However, until very recently our knowledge of the physical characteristics and evolution of this important astrophysical objects was limited to conclusions resulting from the analysis of single-epoch observations of very limited samples (e.g. even in our Galaxy, by the year 2010 still no more than ~20-30 O-stars had reliably determined stellar and wind parameters). This was probably introducing biases in our conclusions and was certainly leaving important puzzling questions still unresolved. To step forward in this field, it became crucial to increase the number of analysed objects the Milky Way and other metallicity environments, also considering the information provided by multiepoch photometric, spectroscopic (multi-wavelength) and spectropolarimetric observations. Only such a complete observational dataset allows the investigation of the impact that third order parameters (such as binarity/multiplicity, magnetic fields, and stellar oscillations) have on the physical and wind properties of massive stars, as well as the evolution of this important astrophysical objects.

Several groups started with the new (21st) century to gather (in parallel) the ground based observational material needed for the new era of investigation of massive stars. Particularly remarkable are

This observational dataset will be perfectly complemented with the asteroseismic observations provided by the CoRoT, Kepler and MOST space missions, and other observations provided by available/planned space satellites such as HST, GAIA, WSO ... The scientific exploitation of this invaluable observational material, coupled with new theoretical advances dealing with stellar evolution and the processes which effect that evolution: mass-loss, rotation, convection, magnetic fields, multiplicity and environment will be certainly at the core of the investigation of massive stars in the next 5-10 years.