Aims: The non-uniform surface temperature distribution of rotating active stars is routinely mapped with the Doppler imaging technique. Inhomogeneities in the surface produce features in high-resolution spectroscopic observations that shift in wavelength because of the Doppler effect, depending on their position on the visible hemisphere. The

The two sources AGC 226178 and NGVS 3543, an extremely faint, clumpy, blue stellar system and a low surface brightness dwarf spheroidal, are adjacent systems in the direction of the Virgo cluster. Both have been studied in detail previously, with it being suggested that they are unrelated normal dwarf galaxies or that NGVS 3543 recently lost its

Context. Clusters of galaxies evolve and accrete mass, mostly from small galaxy systems. Aims: Our aim is to study the velocity field of the galaxy cluster Abell 780, which is known for the powerful radio source Hydra A at its center and where a spectacular X-ray tail associated with the galaxy LEDA 87445 has been discovered. Methods: Our analysis

Using bona-fide black hole (BH) mass estimates from reverberation mapping and the line ratio [Si VI] 1.963$\rm{\mu m}$/Brγ broad as tracer of the AGN ionizing continuum, a novel BH-mass scaling relation of the form log(M BH) = (6.40 ± 0.17) - (1.99 ± 0.37) × log ([Si VI]/Brγ broad), dispersion 0.47 dex, over the BH mass interval, 10 6-10 8 M ⊙ is

Context. The number of super-Earth and Earth-mass planet discoveries has increased significantly in the last two decades thanks to the Doppler radial velocity and planetary transit observing techniques. Either technique can detect planet candidates on its own, but the power of a combined photometric and spectroscopic analysis is unique for an

Context. Proxima Centauri is the closest star to the Sun. This small, low-mass, mid M dwarf is known to host an Earth-mass exoplanet with an orbital period of 11.2 days within the habitable zone, as well as a long-period planet candidate with an orbital period of close to 5 yr. Aims: We report on the analysis of a large set of observations taken