The star counting technique by the PAndAS survey reveals that M33 is undergoing a tidal interaction with its massive neighbor, M31. Due to this interaction, the stellar halo of M33 shows faint tidal features. These features are only visible at extremely low surface brightness levels (i.e. >30 mag/arcsec^2). For this reason, M33 is a perfect test

A number of scenarios have been proposed to explain the low velocity dispersion (and hence possible absence of dark matter) of the low surface brightness galaxies NGC1052-DF2 and NGC1052-DF4. Most of the proposed mechanisms are based on the removal of dark matter via the interaction of these galaxies with other objects. A common feature of these

Recently, the exploitation of spectropolarimetric data has allowed to improve our knowledge of the dynamical and magnetic response of the photospheric and chromospheric layers to the rapid release of energy occurring during solar flares. In this framework, we have used high-resolution observations acquired on 22nd October 2014 during an X1.6

How large-scale structures formed in the early universe is a key cosmological question with few answers from empirical evidence. Unveiling galaxy clusters and their high-z progenitors (i.e., protoclusters) is essential to picture galaxy evolution drawn by the hierarchical formation scenario. However, unveiling these early structures at high

The evolution of galaxies appears linked to the growth of supermassive black holes (SMBH), as evidenced by empirical scale relations between hosts' large-scale properties and the mass of their central black holes. This co-evolutionary scenario suggests that all galaxies experience nuclear activity — active phases during which the black hole

Interstellar gas offers advantages when quantifying the structure of the resonances in disc galaxies. The gas is concentrated close to the disc mid-plane, making it easier to determine its in-plane velocity components, and it offers sharp emission lines for good velocity resolution. These properties are shared by atomic, molecular, and ionized gas