Planetary Nebulae (PNe) are highly representative of the lastest stages of intermediate mass stellar evolution. However, there are still many unresolved questions in their evolutionary scheme. Mass loss processes during the Asymptotic Giant Branch (AGB) are not fully understood. Binarity, rotation and magnetic fields may play an important role in

New optical and near-infrared (NIR) K-band images of the inner 3 kpc region of the nearby Virgo spiral M100 (NGC 4321) display remarkable morphological changes with wavelength. While in the optical the light is dominated by circumnuclear zone of enhanced star formation, the morphological features in the 2.2 micrometer image correspond to a newly

We present the data and initial results from a combined Hubble Space Telescope (HST)/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signal-to-noise ratios than were obtained in our previous multiwavelength

In this paper, we intend to explain the behaviour of the evolved double-lined eclipsing binary TZ Fornacis on the basis of tidal evolution derived from standard theories and the use of modern internal structure stellar models. TZ For is a binary system with a period of 75.7days and a circular orbit, in which the less massive component (1.95Msun_)

White-light images, centered at λ6708A, were obtained at the Swedish Solar Telescope, La Palma, on occasion of the 1994 May 10 partial solar eclipse. From the recorded information, 5 frames showing several pores together with the moon's limb were selected for detailed photometric analysis. The observed intensity profile of the moon's limb projected

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