We present an overview of and first results from the OMEGA (OSIRIS Mapping of Emission-line Galaxies in the multicluster system A901/2) survey. The ultimate goal of this project is to study star formation and active galactic nucleus (AGN) activity across a broad range of environments at a single redshift. Using the tuneable-filter mode of the

The major mass fraction of the envelope of hot luminous stars is radiatively stable. However, the partial ionization of hydrogen, helium, and iron gives rise to extended sub-surface convection zones in all of them. In this work, we investigate the effect of the pressure induced by the turbulent motion in these zones based on the mixing-length

O and early B stars are at the apex of galactic ecology, but in the Milky Way, only a minority of them may yet have been identified. We present the results of a pilot study to select and parametrize OB star candidates in the Southern Galactic plane, down to a limiting magnitude of g = 20. A 2 deg2 field capturing the Carina Arm around the young

We present an analysis of the multiwavelength behaviour of the blazar OJ 248 at z = 0.939 in the period 2006-2013. We use low-energy data (optical, near-infrared, and radio) obtained by 21 observatories participating in the Gamma-Ray Large Area Space Telescope (GLAST)-AGILE Support Program of the Whole Earth Blazar Telescope, as well as data from

Recent studies have shown that the extended main-sequence turn-off (eMSTO) is a common feature of intermediate-age star clusters in the Magellanic Clouds (MCs). The most simple explanation is that these stellar systems harbour multiple generations of stars with an age difference of a few hundred million years. However, while an eMSTO has been

We study a sample of eight massive galaxies that are extreme outliers (3–5σ) in the {M}\bullet ‑ Mbulge local scaling relation. Two of these galaxies are confirmed to host extremely large super-massive black holes (SMBHs), whereas the virial mass estimates for the other six are also consistent with having abnormally large SMBHs. From the analysis