We report V -band and I -band CCD stellar and surface photometry of the galaxy NGC 404 , taken with HST WFPC2 and the 2.5 m Nordic telescope. The colour-magnitude diagram for the stars in this galaxy is typical of that of spheroidal systems (i.e. it lacks luminous, young stars but contains a large number of Asymptotic Giant Branch (AGB) and Red

Using CGS4 on UKIRT, we have obtained a 1.95-2.45 μm infrared (IR) spectrum of the primary candidate counterpart to the bright Z LMXB GX5-1. IR photometry by Naylor, Charles & Longmore and the astrometry of Jonker et al. had previously identified this star as the most likely counterpart to GX5-1. The spectrum presented here clearly shows Brackett γ

Preliminary results from a detailed spectrophotometric analysis of the blue compact dwarf galaxy (BCD) Mrk 35 are presented. We have performed deep UBVRI broad-band and Hα narrow-band optical observations, near-infrared (JHK s) imaging and long-slit spectroscopy of the galaxy. Mrk 35 is composed of a very young starburst population distributed in a

A new approach to the study of the Sun's corona and its dynamical processes is possible with radar investigations in the frequency range of about 10-50 MHz. The range of electron densities of the solar corona is such that radio waves at these frequencies can provide diagnostic radar echoes of large scale phenomena such as coronal mass ejections

It is assumed that the two-fold disc-wide symmetry of spirals is caused by density waves, but also the potential of a bar component may have a significant influence on structural properties. The strength of the bar component appears to be anti-correlated with the degree of symmetry of star-forming regions in the spiral arms (Rozas et al., 1998). We

El trabajo se ha centrado en el estudio de los procesos que acompañan a la emergencia de mancaas en la superficie del sol. Para ello se ha utilizado el método de seguimiento de trazas y el espectroscópico. El primero de ellos permite determinar los movimientos transversales de las estructuras, mientras que el seguno permite medir los movimientos a