Aims: We seek to detect and quantify the effects of surface convection (granulation) on the line spectra of K-dwarfs as a first step towards a rigorous testing of hydrodynamic models for their atmospheres. Methods: Very high-resolution (R≃160 000-210 000), high signal-to-noise ratio (S/N⪆300) spectra of nine bright K-dwarfs were obtained with the

First light of the Gran Telescopio Canarias (GTC) is reviewed by Francisco Sánchez Martínez, encourager of such an endeavour which is today a reality.

We present photometry for globular and open cluster stars observed with the Sloan Digital Sky Survey (SDSS). In order to exploit the over 100 million stellar objects with r

Studying the earliest stages in the birth of stars is crucial for understanding how they form. Brown dwarfs with masses between that of stars and planets are not massive enough to maintain stable hydrogen-burning fusion reactions during most of their lifetime. Their origins are subject to much debate in recent literature because their masses are

About one year after the end of the first observational run and six months after the first CoRoT data delivery, we comment the data exploitation progress for different types of stars. We consider first results to illustrate how these data of unprecedented quality shed a new light on the field of stellar seismology.

The starburst galaxy M82 shows a system of Hα-emitting filaments that extend to each side of the galactic disk. We model these filaments as the result of the interaction between the winds from a distribution of super stellar clusters (SSCs). We first derive the condition necessary for producing a radiative interaction between the cluster winds (a