The outer Large Magellanic Cloud (LMC) have been studied in order to unveil clues about its formation and evolution using both deep color magnitude diagrams and low resolution spectroscopy of red giant branch stars in several fields which span a galactocentric range from 3 to 9 kpc. Our results point to an outside-in evolution scheme in opposition

We report on optical photometry and spectroscopy of the black hole X-ray transient Swift J1910.2-0546/MAXI J1910-057 (Krimm at al. ATel #4139, Usui et al. ATel #4140). R-band photometry (time resolution 27s) over an interval of 3.1 hr was obtained using ALFOSC on the 2.5m Nordic Optical Telescope (NOT) on the night of 21 July 2012. The light curve

Confrontations of spectroscopic observations with local thermodynamic equilibrium (LTE) spectral syntheses in a three-dimensional (3D) hydrodynamical model of the solar photosphere led to a downward revision of the photospheric and meteoritic silicon abundances. Here we derive the photospheric silicon abundance taking into account non-LTE (NLTE)

The low surface brightness usually associated with nebulae mixing with the ISM has long been a substantial obstacle in the observation and statistical study of these interactions. Thanks to the detection capability of the INT Photometric H-alpha Survey (IPHAS), in terms of sensitivity and imaging resolution, we were able to detect and select tens

Aims: The super-Earth planet GJ 1214b has recently been the focus of several studies, which use the transit spectroscopy technique to determine the nature of its atmosphere. Here, we focus on the Hα line as a tool to further restrict the nature of GJ 1214b's atmosphere. Methods: We used the Gran Telescopio Canarias (GTC) OSIRIS instrument to

We present a complete study of the morphology of post-Asymptotic Giant Branch (post-AGB) stars. The post-AGB stage is a very short evolutionary phase between the end of the AGB and the beginning of the Planetary Nebula (PN) stage (between 100 and 10,000 yrs). Post-AGB stars do not show variability and are not hot enough to fully ionize the hydrogen