We have used three large-scale radio surveys to study the spectral behaviour of radio sources towards Abell clusters of galaxies. Without attempting to separate genuine cluster sources from background sources, we find a steeper median spectral index within 0.5 Abell radii (r_A_) than between 0.5 and 1 r_A_ (1 r_A_=3 h_50^-1 Mpc, and H_0 = 50 h_50_

Aims:We aim to understand the real nature of the stellar overdensity at southern galactic latitudes in the region of CMa. Methods: We perform a critical re-analysis and discussion of recent results presented in the literature which interpret the CMa overdensity as the signature of an accreting dwarf galaxy or a new substructure within the Galaxy

We present the results of optical/near-IR observations carried out in the period Dec 1998-Dec 1999 at Spanish, Indian and New Zealand observatories. Most of the searches proved to be unfruitful, in spite of the rapid follow-up observations, starting 3-24 hr after the events. This indicates that a significant fraction of the bursts occur in high

This paper presents the reconstruction of the 80-year time series of daily global solar radiation (GSR) at the subtropical high-mountain Izaña Atmospheric Observatory (IZO) located in Tenerife (The Canary Islands, Spain). For this purpose, we combine GSR estimates from sunshine duration (SD) data using the Ångström-Prescott method over the 1933

The Penn State - Torun Planet Search (PTPS) performed with the Hobby-Eberly Telescope is devoted to search and characterization of extrasolar planetary systems around evolved stars. For complete description of these systems detailed knowledge of their suns is essential. Therefore, in parallel to the planet search we perform a complete spectroscopic

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