We present an overview of the life-cycle of the observing proposals to the GTC and the software tools designed to help the astronomers to create and submit these proposals for evaluation and execution.

The warm star sample (7000 Teff 10,000 K) in SDSS is comprised of field horizontal branch (FHB) stars and a large number of blue straggler (BS) stars. Because these stars have a higher intrinsic luminosity than their cooler, turnoff and main-sequence counterparts, they are an ideal sample for probing both the global properties of the thick disk

We present a long-term project to study the characteristics and evolution of current star-forming galaxies at different redshifts. Our results support the idea that the higher Star Formation Density measured at redshift z=0.24 is due to an increase of the density of bursting galaxies and not to an intrinsic change on overall galaxy properties.

We present results of an optical and near-infrared (IR) 1.8 deg2 survey in the Pleiades open cluster to search for substellar objects. From optical I-band images from the CFHT and J-band images from the 3.5 m CAHA Telescope, we identify 18 faint and very red L brown dwarf candidates, with I> 20.9 and I-J> 3.2. The follow-up observations of nine

The origin and sources of rejuvenated volcanism in Hawaii has been long debated with the depleted isotopic features commonly attributed to assimilation of the 110 Ma-old Pacific oceanic lithosphere underlying Hawaii. Alternatively, it has been recently suggested that this depleted component is a long-lived feature intrinsic to the Hawaiian plume [1

We report recent observational results of some ULXs collected with the 8.2m Subaru and with the ESO VLT telescopes. These observations have provided important information on the (inter-) stellar environments and have allowed to detect the optical counterparts of several ULXs. In two cases spectroscopic observations show stellar HeIIλ4686 optical