In this Letter we report new evidence for a close three-galaxy interaction in the compact group of galaxies HCG 95. Deep optical imaging in the Johnson UBVRI bands and in narrowband H alpha have shown four long tidal tails emanating from the two disk galaxies as well as signs of transfer of material between one of the tidal tails and the elliptical

We have tested current models for the atmospheres (including photosphere and low chromosphere) of late-type stars using the D resonance lines of neutral sodium as a diagnostic. To this end, we have measured the equivalent widths of the D lines for a sample of 39 dwarf and 45 giant late-type stars observed with high spectral resolution. We

The bulge of the Galaxy is analyzed by inverting K-band star counts from the Two-Micron Galactic Survey in a number of off-plane regions. A total area of about 75 sq deg of sky is analyzed. Assuming a nonvariable luminosity function within the bulge, we derive the top end of the K-band luminosity function and the stellar density function, whose

From 1996 June 10 to July 29, the International Ultraviolet Explorer monitored the Seyfert 1 galaxy NGC 7469 continuously in an attempt to measure time delays between the continuum and emission-line fluxes. From the time delays, one can estimate the size of the region dominating the production of the UV emission lines in this source. We find the

We present bidimensional spectroscopy of the central region (9."4 x 12."2) of the Seyfert galaxy NGC 3516 in the two spectral ranges 4186-5839 A and 6110-7890 A. The data (95 x 2 spectra) were simultaneously obtained with an optical fibre system (2D-FIS). The two-dimensional velocity map of the stellar component was obtained from the Mg I b

We have studied the core morphology of the ultraluminous infrared galaxy Mrk 273 by combining a high-resolution adaptive optics near-infrared image with an optical image from the Hubble Space Telescope and interferometric radio continuum data, all at spatial resolutions of 150 mas or better. The near-infrared image reveals that the nucleus has two