Sub-Neptune-sized exoplanets are the most common class discovered by transit surveys, yet their detailed exploration has just begun. Their demographics have inspired models of planetary formation and evolution, though the sample is naturally biased toward the predominance of M-dwarf systems, which provide more favourable observing conditions. We

Context. The interplay between star formation and supermassive-black-hole growth is central to galaxy evolution. While X-ray-selected active glactic nuclei AGNs preferentially reside in star-forming galaxies, the role of host-galaxy morphology in regulating both star-formation enhancement and AGN triggering across the star-forming main sequence

Context. In recent years, a growing amount of evidence has revealed the crucial role of binarity in massive star evolution. This additional complexity compounds the uncertainties that still affect single-star evolution models and demands a refinement of the available observational constraints. A first crucial step toward this goal involves

Context. The presence of massive O-type stars with surfaces enriched by CNO-cycle products has been known since the early 1980s. For many years, internal rotational mixing was assumed to be the dominant mechanism responsible for this chemical contamination. However, accumulating evidence suggests that binary interaction may play an equally

Despite decades of research on hot Jupiters, there are still several theories for their formation. Perhaps hot Jupiters form in several ways. Atmospheric and dynamical studies have the capability to constrain the formation scenarios. However, potential targets have to be well characterized before these observations can further constrain the

Context. Accurate determinations of chemical abundances in H II regions and star-forming galaxies rely critically on robust measurements of the electron temperature (T e) across different ionic species. However, when using a two- or three-zone scheme to approximate the ionisation structure, it is usually possible to measure only a single