Spectroscopic observations of 48 emission-line objects of M 33 have been obtained with the multi-object, wide field, fibre spectrograph AF2/WYFFOS at the 4.2 m WHT telescope (La Palma, Spain). Line intensities and logarithmic extinction, cbeta , are presented for 42 objects. Their location in the Sabbadin & D'Odorico diagnostic diagram (Hα /[S II]

We present low-resolution, integrated Keck spectra of the five globular clusters (GCs) of the Fornax dwarf spheroidal galaxy. We find a tentative age spread among the clusters, with the GC H5 younger by 2-3 Gyr than the others. The clusters generally appear to be very metal-poor ([Fe/H]~-1.8), with the cluster H4 slightly more metal-rich at [Fe/H]=

The morphological properties and spatial distribution of stellar populations are studied for DDO 165 and DDO 181, two dwarf irregular (dIrr) galaxies outside the Local Group. The study uses B and R photometry from which are derived (1) color-magnitude diagrams of the resolved stars, (2) surface brightness profiles for the unresolved stars, and (3)

An important test for models of galaxy formation lies in the metallicity distribution functions (MDFs) of spheroid stars and their globular clusters (GCs). We have compared the MDFs obtained from spectroscopy of the GCs and the star-by-star photometry of the old halo red giants in the nearby elliptical galaxy NGC 5128, with the predictions of a Λ

We present two-dimensional numerical simulations of the evolution of a low-mass star moving supersonically through its surrounding interstellar medium (ISM). We show that the ejecta of a moving star with a systemic velocity of 20 km s-1 will interact with the ISM and will form bow shock structures qualitatively similar to what is observed. We find

We employ the magnetic and velocity fields from turbulent dynamo simulations to synthesize the polarization of a typical photospheric line. The synthetic Stokes profiles have properties in common with those observed in the quiet Sun. The simulated magnetograms present a level of signal similar to that of the Inter-Network regions. Asymmetric Stokes