The formation of collimated outflows or jets in planetary nebulae (PNe) is not well understood. There is no evidence for active accretion discs in PNe, making it difficult to decide which of the several proposed jet formation scenarios may be correct. A handful of wide binary central stars of PNe are known to have accreted carbon and slow neutron

The horizontal branch (HB) morphology of globular clusters (GCs) is mainly described by metallicity. The fact that some clusters with almost the same metallicity exhibit different HB demonstrates that other parameters are at work. We present results from the analysis of the CMD of 72 GCs obtained with the Advanced Camera for Survey (ACS) of the

The detailed study of the different structural components of nearby galaxies can supply vital information about the secular, or internal, evolution of these galaxies which they may have undergone since their formation. We highlight a series of new studies on the thick and thin disk components of galaxies, based on the analysis of mid-infrared

We present the first results of the SUMO project, aimed at studying multiple populations in globular clusters. For this purpose we obtained wide-field photometry in a large sample of clusters using both archival and proprietary U, B, V, and I data from ground-based telescopes. We have defined a new photometric index c_U,B,I=(U-B)-(B-I), that we

We derive the bar fraction in three different environments ranging from the field to Virgo and Coma clusters, covering an unprecedentedly large range of galaxy luminosities (or, equivalently, stellar masses). We confirm that the fraction of barred galaxies strongly depends on galaxy luminosity. We also show that the difference between the bar

Taking advantage of ultra-deep imaging of SDSS Stripe82 and the Hubble Ultra Deep Field by HST, we explore the properties of stellar halos at two relevant epochs of cosmic history. At z˜0 we find that the radial surface brightness profiles of disks have a smooth continuation into the stellar halo that starts to affect the surface brightness