We discuss the prospects for detecting the Rees-Sciama (RS) effect associated with merging clusters of galaxies in millimetric observations. Using the extended Press-Schechter formalism, we characterize the distribution of the parameters describing the mergers, and use these results to generate a mock catalogue of cluster mergers. We use realistic

We present the first results from a large-area (~80deg×20deg), sparsely sampled, two-filter (B and R) imaging survey toward the Canis Major stellar overdensity, which is claimed to be a disrupting Milky Way satellite galaxy. Using stellar color-magnitude diagrams reaching to B~22 mag, we provide a first delineation of its surface density

Available from the Minor Planet Center.

After the recent reports of activity of the accreting millisecond pulsar XTE J1751-305 (ATELs #1045, #1046 and #1051) we obtained another Swift/XRT (~4.3ksec) observation of the field starting on April 11th 2007 23:59. The source was not detected with a 2-10 keV upper limit of ~5E-14 erg/ cm2/s, corresponding to a luminosity of 3.8E32 (d/8kpc)**2

Context: Optical novae have recently been identified as the major class of supersoft X-ray sources in M 31 based on ROSAT and early XMM-Newton and Chandra observations. Aims: This paper reports on a search for X-ray counterparts of optical novae in M 31 based on archival Chandra HRC-I and ACIS-I as well as XMM-Newton observations of the galaxy

Context: Over the last decade a series of results have lent support to the hypothesis of the existence of a long thin bar in the Milky Way with a half-length of 4.5 kpc and a position angle of around 45°. This is apparently a very different structure from the triaxial bulge of the Galaxy. Aims: In this paper, we analyse the stellar distribution in