We present new observations of the center-to-limb variation of spectral lines in the quiet Sun. Our long-slit spectra are corrected for scattered light, which amounts to 4-8% of the continuum intensity, by comparison with a Fourier transform spectrum of the disk center. Different spectral lines exhibit different behaviors, depending on their

We present a complete analysis, which includes morphology, kinematics, stellar populations, and N-body simulations, of CGCG 480-022, the most distant (cz=14,317 km s-1) isolated galaxy studied so far in such detail. The results all support the hypothesis that this galaxy has suffered a major merger event with a companion of ~0.1 times its mass

Since the beginning of the ESPRESSO (Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations) project, it has been recognized that the expected challenging scientific results can be achieved only if an integrated view of the end-to-end operations is properly tackled. Hunting for rocky exoplanets and/or studying the possible

We report the discovery of 2 previously unseen X-ray sources detected in a 5ks Chandra/ACIS observation starting on 2008-09-01.32 UT as part of our ongoing Chandra/HST M31 transient program (see also ATel #1693 for more results from this observation). Due to the low count-rate, no spectral fitting was possible. The reported luminosities have been

We report on Chandra ACIS-S observations of five type I X-ray bursters with low persistent emission: SAX J1324.5-6313, SAX J1752.3-3128, SAX J1752.3-3128I, SAX J1324.5-6313V, and SAX J1818.7+1424. We designate candidate persistent sources for four X-ray bursters. All candidates are detected at a persistent luminosity level of 1032-33 erg s-1

We have detected two globular clusters in the nuclear region of M31 with both Chandra and HST. These detections allow us to register the Chandra and HST images and therefore determine relative positions to ~0.1''. This improved positional accuracy shows that (contrary to our earlier reports) neither CXOU J004244.2+411608 nor CXOU J004244.2+411609