This thesis is divided into two very related parts. In the first part we implement and apply a galaxy cluster detection method, based on multiband observations in visible. For this purpose, we use a new algorithm, the Voronoi Galaxy Cluster Finder, which identifies overdensities over a Poissonian field of objects. By applying this algorithm over

Comet C/2001 Q4 (NEAT) was observed at ESO (La Silla) for three consecutive nights at the beginning of May, 2004 at its closest approach to Earth. The observations consisted of quasi-simultaneous multi-wavelength exposures in the visible, near-IR and thermal-IR in order to study different properties of the solid component that are responsible for

We have performed the first extensive analysis of the impact of an [α/Fe]>0 metal distribution on broadband colors in the parameter space (surface gravity, effective temperature, and metal content) covered by Galactic globular cluster stars. A comparison of updated and homogeneous ATLAS 9 UBVRIJHKL synthetic photometry, for both α-enhanced and

Climate diagnostic studies combine data from different sources (radiosoundes, satellites, meteorological masts, etc) and meteorological models to predict the climate conditions and evolution at a particular site or globally. Products from climate diagnosis are archived in long-term databases that may constitute a useful tool for site

We present integral field spectroscopy (IFS) of the central region of 3C 120. We have modeled the nuclear and host galaxy three-dimensional spectra using techniques normally applied to imaging, decoupling both components and obtaining a residual data cube. Using this residual data cube, we detected the extended emission line region associated with

This thesis investigates the abundance and properties of extremely red galaxies (EROs). Although the existence of such conspicuous galaxies has been known for some time, there are numerous open questions regarding their nature, formation, and evolution. One reason is the number of different colour criteria applied to select EROs. Hence, different