There are two main types of photoionized gaseous nebulae that exist in the universe: H II regions and Planetary Nebulae (PNe). They mark the endpoints of stellar evolution and understanding their composition will lead to a better understanding of stellar evolution processes and galactic chemical nucleosynthesis. Elemental abundances are estimated

Forthcoming large-scale spectroscopic surveys will soon provide data on thousands of galaxy clusters. It is important that the systematics of the various mass estimation techniques is well understood and calibrated. We compare three different dynamical mass estimators using the C-EAGLE galaxy clusters, a set of high-resolution simulations with

Context. The physical processes driving the evolution of star formation (SF) in galaxies over cosmic time still present many open questions. Recent galaxy surveys allow now to study these processes in great detail at intermediate redshift (0 ≤ z ≤ 0.5). Aims: We build a complete sample of star-forming galaxies and analyze their properties, reaching

Context. Solar active regions show a wide variety of oscillatory phenomena. The presence of the magnetic field leads to the appearance of several wave modes whose behavior is determined by the sunspot thermal and magnetic structure. Aims: We aim to study the relation between the umbral and penumbral waves observed at the high photosphere and the

Las estrellas O representan una fase fundamental en el zoológico de las estrellas masivas. Ionizan el material a su alrededor e inundan su entorno con material procesado a través de fuertes vientos estelares y explosiones de supernova. Además de la pérdida de masa, factores como la rotación y la multiplicidad (así como la interacción entre ellos)

The physical processes related to the formation, evolution and disappearance of solar active regions are not completely clear. High-resolution solar spectro-polarimetric data are needed to investigate these processes with unprecedented details. Here we present the analysis of the short-lived NOAA 12549 active region using high-resolution spectro