Between February 2010 and May 2011, our group has observed five stellar occultations by Trans-Neptunian Objects (TNOs), giving the size and shape for some of the biggest TNO's: Varuna, Eris, 2003 AZ84, Makemake and Quaoar. Here we present two of them: the January 08 stellar occultation by 2003 AZ84, and the May 04 by Quaoar. For the event of 2003

While studies of gas-phase metallicity gradients in disc galaxies are common, very little has been done towards the acquisition of stellar abundance gradients in the same regions. We present here a comparative study of the stellar metallicity and age distributions in a sample of 62 nearly face-on, spiral galaxies with and without bars, using data

Aims: We present MUFFIT, a new generic code optimized to retrieve the main stellar population parameters of galaxies in photometric multi-filter surveys, and check its reliability and feasibility with real galaxy data from the ALHAMBRA survey. Methods: Making use of an error-weighted χ2-test, we compare the multi-filter fluxes of galaxies with the

Within the hierarchical framework for galaxy formation, minor merging and tidal interactions are expected to shape all large galaxies to the present day. As a consequence, most seemingly normal disk galaxies should be surrounded by spatially extended stellar "tidal features" of low surface brightness. As part of a pilot survey for such interaction

Consideration is given to the suppression of the radial and polar escape of magnetic flux in the form of toroidal flux tubes (flux rings) from low latitudes in the overshoot region below the solar convection zone through the combined action of the subadiabatic ambient stratification and the rotationally induced forces. It is shown that a flux ring

An analysis of the 5 minute oscillation in the solar photosphere has been carried out using an inversion of the radiative transfer equation applied to a time-series of K I lambda 7699 line spectra with a 5" x 5" window at disk center. A thorough discussion of the inversion conditions, with special emphasis on the LTE approach and a careful error