Planets orbiting close to hot stars experience intense extreme-ultraviolet radiation, potentially leading to atmosphere evaporation and to thermal dissociation of molecules. However, this extreme regime remains mainly unexplored due to observational challenges. Only a single known ultra-hot giant planet, KELT-9b, receives enough ultraviolet

We divide this talk into two parts. In the first part, we will introduce the numerical codes we use, mainly in solar physics, to infer information about the solar atmosphere from spectro-polarimetric observations. In particular, we will present a new version that was recently developed (see Ruiz Cobo et al., 2022). In the second part of the talk

Durante los últimos 45 años, el grupo de Sismología Solar (y Estelar y Búsqueda de Exoplanetas) del Instituto de Astrofísica de Canarias, ha estado observando ininterrumpidamente los patrones espaciales y temporales de vibración del Sol. He estado involucrado en esta increíble aventura durante los últimos 30 años, intentando relacionar las