Recent observational studies suggest that feedback from active galactic nuclei (AGNs) may play an important role in the formation and evolution of low-mass dwarf galaxies, an issue that has received little attention from a theoretical perspective. We investigate this using two sets of 12 cosmological magneto-hydrodynamical simulations of the

Ultra-diffuse galaxies (UDGs) are attractive candidates to probe cosmological models and test theories of galaxy formation at low masses; however, they are difficult to detect because of their low surface brightness. In the Local Group a handful of UDGs have been found to date, most of which are satellites of the Milky Way and M31, and only two are

The dynamical study of nearby dwarf spheroidal galaxies has played a fundamental role in challenging the cold dark matter model. These studies, based on the analysis of resolved stellar populations, are limited by the fact that we can only probe a small population of the nearest nearby galaxies. In the coming years, ultra-deep surveys will increase

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