Context. Our knowledge of the dynamics of stars has undergone a revolution through the simultaneous large amount of high-quality photometric observations collected by space-based asteroseismology and ground-based high-precision spectropolarimetry. They allowed us to probe the internal rotation of stars and their surface magnetism in the whole

We report on an ongoing search for biomarkers in the potentially habitable atmospheres of a sample of a dozen Y dwarfs with Teff estimated at around or below 400 K. This work is being carried out using public data from large area optical surveys such as DES and PANStarrs. We focus on a search for g-band emission as an analogue to terrestrial

The sizable linear polarization signals produced by the scattering of anisotropic radiation in the core of the Ca I 4227 Å line constitute an important observable for probing the inhomogeneous and dynamic plasma of the lower solar chromosphere. Here we show the results of a three-dimensional (3D) radiative transfer complete frequency redistribution