Extremely faint galaxies (mu_V>27 mag/arcsec^2), have only been discovered in the Local Group. These galaxies are very low in mass (tens of 10^5 Msun) and compact (effective radius <1 kpc). These objects populate the least massive dark matter haloes capable of producing stars, providing us with valuable insights into the nature of star formation at

The deepest ground-based optical surveys (in terms of surface brightness mu~31 mag/arcsec^2) show that we are close to the dreaded source confusion limit. The typical distance between sources in these images is a few arcseconds, on the order of the natural seeing in these images. When this source confusion limit is reached, low surface brightness

Bars are ellipsoidal-like structures that appears in the inner regions of a large fraction of discs of galaxies. Bars universal features present at all galactic masses, morphological types and across the Hubble time. Stars forming bars follow elongated orbits aligned with the bar major-axis. These barred structures rotate as a coherent structure

The derivation of precise stellar ages is considered the current major challenge to reconstruct the chronological chain of events that shaped the Milky Way (MW). Despite much effort and hope have been deposited in upcoming asteroseismology works, we have shown that CMD-fitting already offers an alternative to age determinations via the derivation

Over the past decade, microlensing surveys in field stars and the Gaia-informed census of nearby star-forming regions have convincingly demonsrated the presence of a significant population of free-floating planetary-mass objects. The origin of these objects is still debated, with the main plausible scenarios being: the dynamical ejection from a

Dwarf irregular galaxies, due to their lower masses, relative isolation, and high-quality data availability, are ideal laboratories to test various models of dark matter. In particular, the existence, morphology and formation of central cores in dwarf galaxies has been a contentious issue in the literature in light of apparent tensions with the