The characteristics of the halo gas and its interaction with the galactic disk in spiral galaxies are poorly known; this is particularly true for the warm neutral gas associated with HVCs and galactic chimneys. The detection of absorption features such as the NaI D or the CaII (H,K) lines is instrumental to study its detailed physical properties

Magnetic fields play an important role in astrophysics and they often dominate the behavior of magnetized media. We simulate the mechanism (Tagger et al., 1995) by which turbulence in a weakly ionized plasma, as it cascades to the ambipolar scale (where the neutrals are imperfectly coupled to the ions) leads to a filamentation of the magnetic flux

Not Available

Not Available

We show the results of a mid and far IR study of ISO data of the CfA Seyfert sample. These data allow a detailed study of the far IR Spectral Energy Distribution (SED) of these galaxies. We find that the mid and far IR SED of Seyfert galaxies can be explained solely through thermal reradiation of high energy photons by dust, and, that this thermal

We present the current status of our knowledge on the photospheric abundances of massive blue stars (with spectral types O-A) in the Milky Way and Local Group galaxies, and the implications of these for stellar and galactic structure and evolution. We also consider possible extensions of this project to observe individual stars in galaxies beyond