We present evidence for a morphological segregation of early-type galaxies with different isophote shapes in the Virgo cluster. Comparing local projected densities around galaxies, we find that, independently of their classification as elliptical or lenticular, galaxies with boxy isophotes are located in local density enhancements, while galaxies

We present the results of a 6 month monitoring campaign of Mkn 876, a low luminosity quasar with M_abs_=~-24. High resolution spectroscopy and direct imaging in the Johnson filters B, V, R, I was carried out in the first half of 1990. Line and continuum light curves are presented. Mkn 876 showed a decrease of 17% in the continuum over the whole

Major axis rotation curves and velocity dispersions profiles, extending out to about one effective radius, are presented for 15 ellipticals and S0's out of the photometric sample of Fornax cluster galaxies studied by Caon et al. (1994). A brief description of the spectroscopic and photometric characteristics of each galaxy is provided, together

Linear, quadratic, and square root limb-darkening coefficients have been computed by means of least squares fits to model atmospheres by Kurucz (1991) with the main purpose of facilitating the analysis of light curves of eclipsing binaries. Results are compared with previously published values using the same or different models and various fitting

In most papers dealing with random motions and diffusion of small magnetic elements in the photosphere, the convective flows and in particular the granulation are considered as drivers of these motions. The results of these works have been discussed in terms of the fractal dimension of the granulation as seen in intensity pictures. So far neither a

Measurement of pattern speeds has been an observational imperative in the last years since a clear determination of the corotation resonance radius will give some insight in the nature of density waves and in the mechanism of their maintenance. In this paper we analyse in detail the practical application to the grand design spiral NGC 4321 of two