El estudio de las abundancias solares se remonta al análisis de Russell de 1929 y, desde entonces, se ha vuelto un tema muy relevante para la astrofísica en general. Esto es debido a que conocer la composición química del Sol es fundamental para construir modelos precisos de la atmósfera y el interior del Sol y de otras estrellas. Además, la

A lo largo de las últimas decadas, importantes evidencias observacionales han revelado que los Cúmulos Globulares (CG) en la Vía Láctea albergan distintas poblaciones estelares. Representando clásicamente los mejores ejemplos en la naturaleza de Poblaciones Estelares Simples, estos nuevos hallazgos han puesto a los CG en el centro de atención. En

Over 2,000 stars were observed for one month with a high enough cadence in order to look for acoustic modes during the survey phase of the Kepler mission. Solar-like oscillations have been detected in about 540 stars. The question of why no oscillations were detected in the remaining stars is still open. Previous works explained the non-detection

We report Spitzer Space Telescope observations during predicted transits of the exoplanet Proxima Centauri b. As the nearest terrestrial habitable-zone planet we will ever discover, any potential transit of Proxima b would place strong constraints on its radius, bulk density, and atmosphere. Subsequent transmission spectroscopy and secondary

Recent observations of the solar photosphere revealed the presence of elongated filamentary bright structures inside sunspot umbrae, called umbral filaments (UFs). These features differ in morphology, magnetic configuration, and evolution from light bridges (LBs) that are usually observed to intrude in sunspots. To characterize a UF observed in the

The aim of this work is to provide a methodology to model the dielectric properties of human tissues based on phantoms prepared with an aqueous solution, in a semi-solid form, by using off-the-shelf components. Polyvinyl alcohol cryogel (PVA-C) has been employed as a novel gelling agent in the fabrication of phantoms for microwave applications in a