We have studied 116 bright galaxies from the Coma Cluster brighter than mr=17 mag. From a quantitative morphological analysis we find that the scales of the disks are smaller than those of field spiral galaxies. There is a correlation between the scale of the disks and the position of the galaxy in the cluster; no large disks are present near the

We present the first time-resolved spectroscopic study of the cataclysmic variable DW Cancri. We have determined an orbital period of 86.10 +/- 0.05 min, which places the system very close to the observed minimum period of hydrogen-rich cataclysmic variables. This invalidates previous speculations of DW Cnc being either a permanent superhumper

I present a catalog of 67 barred galaxies which contain distinct, elliptical stellar structures inside their bars. Fifty of these are double-barred galaxies: a small-scale, inner or secondary bar is embedded within a large-scale, outer or primary bar. I provide homogenized measurements of the sizes, ellipticities, and orientations of both inner and

We report new spectroscopic results, obtained with UKIRT/CGS4, of a sample of 14 candidate ultracool dwarfs selected from the DENIS (Deep Near-Infrared Survey of the Southern Sky) database. A further object, selected from the 2MASS Second Incremental Release, was observed at a later epoch with the same instrument. Six objects are already known in

We present BV photometry centered on the globular cluster M54 (NGC 6715). The color-magnitude diagram clearly shows a blue horizontal branch extending anomalously beyond the zero-age horizontal-branch theoretical models. These kinds of horizontal-branch stars (also called ``blue hook'' stars), which go beyond the lower limit of the envelope mass of

Here we report the first detection of polarization signals induced by the Zeeman effect in spectral lines of the E4Π-A4Π system of FeH located around 1.6 μm. Motivated by the tentative detection of this band in the intensity spectrum of late-type dwarfs, we have investigated the full Stokes sunspot spectrum and have found circular and linear