We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing two small transiting planets. The inner planet, HD 15906 b, was detected with an unambiguous period but the outer

HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R ⊕ (HIP 9618 b) and 3.343 ± 0.039 R ⊕ (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a

The heart of this thesis is the multiwavelength (MWL) study of a special subclass of active galactic nuclei (AGN) called blazars. These objects host a supermassive black hole as their central engine. They present a relativistically boosted jet that points towards the Earth, acting as a natural particle accelerator, emitting over the entire

A lo largo de la historia de la humanidad, las distintas culturas incorporaron cuerpos y fenómenos celestes a su folclore, dando cuenta de su interés y fascinación por el firmamento. En la actualidad, incluso cuando la observación de los movimientos de los astros no es necesaria en nuestro día a día para la ubicación en el tiempo y en el espacio

According to the standard cosmological model, structure formation occurs in a bottom up fashion, where small galaxies are formed first while bigger systems grow by continuous aggregation of smaller ones. Both observations and theoretical predictions of the galaxy mass function agree on the fact that dwarfs are the most numerous galaxies in the

El trabajo realizado en esta Tesis Doctoral se enmarca en el contexto de dos aspectos fundamentales del mundo de la Ciencia: la investigación y la divulgación. Así, la primera parte se desarrolla en la sinergia entre la Astrosismología en estrellas de tipo solar y la caracterización de exoplanetas, a partir de observaciones fotométricas de alta