The PN M2-48 is formed by three main structures, namely, a bipolar central region (CR), a set of knots tracing a semicircular shell surrounding CR, and two symmetric bow-shocks. CR shows a kinematic structure corresponding to a bipolar shell, with an expansion velocity of =~ 50kms-1. The semicircular shell appears to be expanding at =~ 20kms-1

We present the first results on the identifications of a medium sensitivity survey (X-ray flux limit 2x 10-14 erg cm-2 s-1 in the 0.5-4.5 keV band) at high galactic latitude ({mid}b{mid}>20deg) carried out with the XMM-Newton X-ray observatory within the AXIS observing programme. This study is being conducted as part of the XMM-Newton Survey

We compute photoionization models for the giant extragalactic H II region NGC 5461, and compare their predictions to several observational constraints. The models are constrained to reproduce the observed density profile, and our analysis takes into consideration the bias introduced by the shapes and sizes of the slits used by different observers.

We undertook two time-series photometric multisite campaigns for the rapidly oscillating Ap star HD 122970. The first one, conducted in 1998, resulted in 119h of data and in the detection of three pulsation frequencies. The presence of possible further modes which held the promise of deriving a mode identification motivated a second worldwide

Several authors have suggested that a link exists between the flux of galactic cosmic rays (GCR) and cloudiness. Here we review the evidence for such a connection from studies of cloud factors using both satellite and ground-based data. In particular, we search for evidence for the low cloud decrease predicted by the rising levels of solar activity

We demonstrate that the atomic alignment of the hyperfine-structure components of the ground-level S1/2 of Na I and of the upper-level P1/2 of the D1 line are practically negligible for magnetic strengths B>10 G and virtually zero for B>~100 G. This occurs independently of the magnetic field inclination on the stellar surface (also, in particular