Once the need for an iterative procedure in order to solve the problem of the formation of spectral lines in the case of a model atom with many energy levels, the sequel is to seek for the most effective form of such an iterative scheme. It is an almost universal is assumed within all the iterative methods for the solution of those radiative

We present 29 mid-infrared spectra of the zodiacal light distributed over the sky. The observed 5.9-11.7 mu m spectral shapes are well represented by blackbody radiation with colour temperatures in the range of 255

LIRIS is an Instituto de Astrofísica de Canarias (IAC) project that consists in a near-infrared (0.9-2.4microns) intermediate resolution spectrograph, conceived as a common user instrument for the WHT. LIRIS will have imaging, long-slit and multi-object spectroscopy observing modes (~1000-3000 Å). Coronography, and polarimetry capabilities will

We investigate the spatial, kinematic and chemical properties of globular cluster systems formed in merging and interacting galaxies using N-body-smoothed particle hydrodynamics (SPH) simulations. Although we cannot resolve individual clusters in our simulation, we assume that they form in collapsing molecular clouds when the local external gas

Some observations suggest that quiescent solar prominences can be considered as composed by small-scale loops, or fibrils, which are stacked one after another in both the vertical and horizontal directions. In a previous work we studied, in Cartesian geometry, the propagation of fast MHD waves in a two-dimensional magnetostatic model representing

Time series of images of a sunspot, acquired simultaneously in blue light and in G-band at the SVST, La Palma, are used to study horizontal motions of granules in the vicinity of the spot and evolution of penumbral grains (PGs) near the outer penumbral border. Local correlation tracking and feature tracking algorithms have been utilized for this