We present R-band light curves of BL Lacertae from May 2000 to January 2001, obtained by 22 telescopes in 11 countries. More than 15000 UBVRI observations were...

The Whole Earth Blazar Telescope (WEBT) is an international consortium of about 30 optical observatories and 2 radio observatories devoted to blazar monitoring...

The basic capabilities of the Wide Field Imager (WFI) were described in a previous Messenger article (No. 93, p. 13; see also Table 1) which also includes a...

An analysis of the center to limb variation of the geometrical properties of spots has been carried out. It has revealed that spots do not have a symmetrical...

We derived consistent photospheric and wind parameters of O-type stars, by analyzing high-resolution spectra in the range 905 to 3250 Å with line-blanketed...

High resolution spectrophotometry of the black hole system V404 Cyg during quiescence, performed during 1990 and 1991, is discussed. In addition to a 6.5d...

The data provided by the ESA INTEGRAL mission have revealed the presence of a huge new population of HMXB sources. Among them, an important fraction belong to...

Not Available

The analysis of the X-ray data for a sample of 51 LINER nuclei with available X-ray Chandra imaging is reported. Our aim was to investigate the physical...