This thesis comprises of a full search in our galaxy for the hidden population of massive stars using the near-infrared photometry with a novel method and a quantitative spectroscopy study of an O star sample in the optical and near-infrared. Massive clusters are those with mass greater than 10^4 Solar Masses . The number of known massive clusters

Los cartografiados celestes han sido, históricamente, el principal método de obtención de datos astronómicos para el estudio del Universo. Esta tesis se centra en uno de ellos, OTELO, un cartografiado en líneas de emisión que utiliza los filtros sintonizables del instrumento OSIRIS del Gran Telescopio CANARIAS, actualmente el mayor telescopio

Among the latest developments in Adaptive Optics (AO) systems, Multi Object Adaptive Optics (MOAO) systems span a large sensing field of view in the order of arcminutes, and correct only the small portions of the sensed field of view where the scientific objects of interest are situated, in the order of arcseconds each. Thus, they operate in open

Since the 1995 discovery of the first exoplanet orbiting a solar-type star (Mayor & Queloz 1995), the number of these has grown exponentially. To date, more than 4,500 planets have been detected (more than 3,200 confirmed). In addition, the size of these planets is very diverse, from giant Jupiter-type planets (the first to be discovered) to Earth

The accurate characterization of the physical properties of massive stars in very low-metallicity environments has important implications in our interpretation of the primitive Universe. The first population of stars, which are thought to have been very massive and extremely metal-poor, has been proposed as the responsible source of the re

La espectroscopía es una de las fuentes de información más valiosas de que dispone la astrofísica estelar. La correcta interpretación de los espectros estelares es vital en muchos campos, ya que de ellos se derivan los parámetros fundamentales de las estrellas, su rotación, composición química, velocidad radial, etc. y, a partir de espectros de