In this thesis, we focus on studying the properties of the large-amplitude prominence oscillations (LAOs) using the realistic prominence models and the triggering of such motions by external perturbations. LAOs involve motions with velocity amplitudes above 20 km/s, and large portions of the filament move in phase, indicating a strong connection

Up to now, WASP-12b is the only hot Jupiter confirmed to have a decaying orbit. The case of WASP-43b is still under debate. Recent studies preferred or ruled out the orbital decay scenario, but further precise transit timing observations are needed to definitively confirm or refute the period change of WASP-43b. This possibility is given by the

Context. Despite their importance, routine and direct measurements of electric currents, j, in the solar atmosphere have generally not been possible. Aims: We aim at demonstrating the capabilities of a newly developed method for determining electric currents in the solar photosphere. Methods: We employ three-dimensional radiative magneto

In this work we present the results of a direct imaging survey for brown dwarf companions around the nearest stars at the mid-infrared 10 micron range (λ c = 8.7 μm, Δλ = 1.1 μm) using the CanariCam instrument on the 10.4 m Gran Telescopio Canarias (GTC). We imaged the 25 nearest stellar systems within 5 pc of the Sun at declinations δ > -25° (at

Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a

The geometric characteristics of dust clouds provide important information on the physical processes that structure such clouds. One of such characteristics is the 2D fractal dimension D of a cloud projected on to the sky plane. In previous studies, which were mostly based on infrared (IR) data, the fractal dimension of individual clouds was found