Quantitative information about variations in the background at J and K' are presented and used to develop guidelines for the acquisition and reduction of ground-based images of faint extended sources in the near-infrared, especially those that occupy a significant fraction of the field of view of a detector or that are located in areas crowded with

SS433 is the prototype microquasar in the Galaxy and may even be analogous to the ULX sources if the jets' kinetic energy is taken into account. However, in spite of 20 years of study, our constraints on the nature of the binary system are extremely limited as a result of the difficulty of locating spectral features that can reveal the nature and

Smart Focal Planes are devices that enable the efficient sampling of a telescope's focal plane to feed spectroscopic and imaging instruments. Examples are integral field units (fiber and image slicers), cryogenic beam manipulators, and MOEMS (micro-opto-electromechanical systems) such as miniature slit shutters. These technologies are critical in

The site selection for the future large European telescope is a key issue, which will be addressed within the Euorpean proposal to be submitted to be funded by the EECC within the ELT design studies proposal. The organization, working scheme and baseline frameworks have been discussed and planned and are summarized here. For the definition of the

The Observatorio Astronomico Nacional at San Pedro Martir is situated on the summit of the San Pedro Martir Sierra in the Baja California peninsula of Mexico, at 2800m above sea level. For as long as three decades, a number of groups and individuals have gathered extremely valuable data leading to the site characterization for astronomical

We present here the results of a search for new microquasars at low galactic latitudes, based on a cross-identification between the ROSAT all sky Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) and follow-up observations. The results obtained up to now suggest that persistent/silent microquasars such as LS 5039 are rare objects in