As part of a systematic effort to characterize the properties and progenitors of the most luminous planetary nebulae (PNe), we obtained a sample among the brightest PNe in two stellar systems of different metallicities: LMC (Z/Z⊙~0.5) and M31 (Z/Z⊙~1) by means of a combined effort with the VLT and the 10mGTC. Modelling of these data will allow us

We analyse the poorly studied open cluster King 1 in the second Galactic quadrant. From wide-field photometry, we have studied the spatial distribution of this cluster. We determined that the centre of King 1 is located at α2000 = 00h22m and δ2000 = +64°23΄. By parameterizing the stellar density with a King profile, we have obtained a central

At the interface of H ii regions and molecular gas, peculiar structures appear, some of them with pillar-like shapes. Understanding their origin is important for characterizing triggered star formation and the impact of massive stars on the interstellar medium. In order to study the molecular environment and influence of radiation on two pillar

Context. The O6 Vn star HD 64315 is believed to belong to the star-forming region known as NGC 2467, but previous distance estimates do not support this association. Moreover, it has been identified as a spectroscopic binary, but existing data support contradictory values for its orbital period. Aims: We explore the multiple nature of this star

In Planetary Nebulae (PNe) and HII regions ionic abundances can be derived by using collisionally excited lines (CELs) or recombination lines (ORLs). Such abundances do not coincide for the same ion and usually abundances from ORLs are larger than those from CELs by factors of 2 or larger. The origin of the discrepancy, known as the Abundance

We introduce the Hydrangea simulations, a suite of 24 cosmological hydrodynamic zoom-in simulations of massive galaxy clusters (M200c = 1014-1015.4 M⊙) with baryon particle masses of ˜106 M⊙. Designed to study the impact of the cluster environment on galaxy formation, they are a key part of the `Cluster-EAGLE' project. They use a galaxy formation