IZw18 is one of the lowest-metallicity star-forming galaxies known at z ∼ 0, considered a unique local analogue of the first galaxies. The origin of its hard ionizing continuum, expected to be a common feature in the early Universe and traced by He II emission lines, remains intensely debated and challenging to explain. Here we combine optical Gran

To investigate the impact of winds and jets with a low to moderate power on the cold molecular gas reservoirs of active galactic nuclei (AGN), we present observations with a high angular resolution with ALMA CO(2–1) and CO(3–2) of a sample of six type 2 quasars (QSO2s) at z ∼ 0.1 from the quasar feedback (QSOFEED) sample. We used spatially resolved

Aims. The light curves of the microlensing events MOA-2022-BLG-091 and KMT-2024-BLG-1209 exhibit anomalies with very similar features. These anomalies appear near the peaks of the light curves, where the magnifications are moderately high, and are distinguished by weak caustic-crossing features with minimal distortion while the source remains

Context. Forced magnetic reconnection is triggered by external perturbations, which are ubiquitous in the solar corona. This process plays a crucial role in the energy release during solar transient events, which are often associated with electric current sheets (CSs). The CSs can often disintegrate through the development of the tearing

Context. Investigating whether and how galaxy mergers affect black hole growth can be a determinant for black hole-galaxy coevolution models and, in particular, for understanding how early Universe seed black holes grew to become supermassive. However, while mergers have been observed to enhance the active galactic nucleus (AGN) activity and thus

Cosmic birefringence (CB) is the rotation of the photons' linear polarisation plane during propagation. Such an effect is a tracer of parity-violating extensions of standard electromagnetism and would probe the existence of a new cosmological field acting as dark matter or dark energy. It has become customary to employ cosmic microwave background