Metal-poor ultracool dwarfs (ultracool subdwarfs, including very-low-mass stars and brown dwarfs) are tracers of the pristine chemical composition at early phases in the assembly of the Milky Way. They are poorly understood because they are extremely faint and rare. Our aims are to improve the knowledge of ultracool subdwarf candidates, to break

MUDEHaR has completed its first of five years of project, and all the information is already available for exploitation. MUDEHaR is a multi-epoch photometric survey with two narrow filters in Hα and the calcium triplet window that uses T80Cam at the JAST80 telescope at Javalambre spanish astronomical observatory. It is obtaining ~50 epochs/year per

Simultaneous multicolor photometry is an important source of observational data providing priceless information on different physical processes that cannot be obtained in other ways. It can provide modal identification for classical pulsators, information about the stellar spots structure, or clues for identifying false positives in exoplanetary

Ultra-diffuse galaxies (UDGs) have been one of the latest hypes in the extragalactic community. Although discovered a few decades ago, only recently we have had the opportunity to start grasping their nature thanks to deep photometric observations and, more challengingly, spectroscopic ones. From different properties ranging from their dark matter

The High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph (HARMONI) is a first generation instrument designed for the Extremely Large Telescope (ELT). HARMONI offers operational versatility, enabling both seeing-limited (NOAO) operation and compensation for atmospheric optical turbulence using two systems: Single

The ESA PLATO (PLAnetary Transits and Oscillations of stars) mission aims at the detection and characterisation (radii, mass, density, age) of terrestrial exoplanets in orbits up to the habitable zone around Sun-like stars. To achieve these goals, an optimised complementary Ground-based Observations Programme (GOP) is set up with the purpose to