Large segmented mirrors require efficient co-phasing techniques in order to avoid the image degradation due to segments misalignment. DIPSI (Diffraction Image Phase Sensing Instrument) is an instrument developed by IAC, GRANTECAN and LAM. This instrument is being integrated in the Active Phasing Experiment (APE), aimed at testing different phasing

The European Extremely Large Telescope (E-ELT) is a 42-m class optical telescope with a segmented primary mirror composed of 984 segments which is currently being studied by ESO (European Southern Observatory). The segment support system combines a series of mechanical whiffletrees for the axial support, a central diaphragm for lateral support and

We present in this paper the new cute-SCIDAR instrument, entirely developed by the Instituto de Astrofísica de Canarias (IAC), delivered recently at the European Southern Observatory (ESO) Paranal Observatory (Chile). This instrument, supported by the European Community (Framework Programme 6, Extremely Large Telescope Design Study), carries out

We propose to obtain the most detailed and accurate star formation and chemical evolution histories of two nearby southern dwarf spheroidal galaxies, Fornax and Sculptor, by means of detailed Color-Magnitude Diagram (CMD) analyses of the resolved stellar populations. This requires deep multi-color imaging with CTIO/MOSAIC calibrated to the highest

High-resolution observations provide evidence of the existence of small-amplitude transverse oscillations in solar filament fine structures. These oscillations are believed to represent fast magnetohydrodynamic (MHD) waves, and the disturbances are seen to be damped on short timescales of the order of 1-4 periods. In this Letter, we propose that

Aims: We observed a new cataclysmic variable (CV) SDSS J080434.20+510349.2 to study the origin of long-term variability found in its light curve. Methods: Multi-longitude, time-resolved, photometric observations were acquired to analyze this uncommon behavior, which has been found in two newly discovered CVs. Results: This study of SDSS J080434.20