Context: The recent discovery of a group of trans-neptunian objects (TNOs) in a narrow region of the orbital parameter space and with surfaces composed of almost pure water ice, being 2003 EL{61} its largest member, promises new and interesting results about the formation and evolution of the TNb and the outer Solar System. Aims: The aim of this

We report the discovery of two previously unseen X-ray sources detected in a 5ks Chandra/ACIS observation starting on 2008-10-13.15 UT as part of our ongoing Chandra/HST M31 transient program. Due to the low number of counts, no detailed spectral analysis was possible. The spectra were modelled with an absorbed power law of nH = 6.67e20 atoms/ cm2

The surface-brightness profiles of galaxy disks fall into three main classes, based on whether they are simple exponentials (Type I), bend down at large radii (Type II, `truncations') or bend up at large radii (Type III, `antitruncations'). Here, we discuss how the frequency of these different profiles depends on Hubble type, environment, and the

At present, ten years after they were first discovered, ten accreting millisecond pulsars are known. I present a study of the aperiodic X-ray variability in three of these systems, which led to the discovery of simultaneous kHz quasi periodic oscillations in XTE J1807-294 and extremely strong broadband noise at unusually low variability frequencies

Although full interoperability between theoretical and observational data in the framework of the Virtual Observatory would be a very desirable achievement, the current status of VO offers few approaches to handle theoretical models. TSAP (Theoretical Spectra Access Protocol) has been proposed as a tool to fill this void, providing a simple scheme

Context: We present an extensive ground-based photometric and spectroscopic campaign of the γ Dor CoRoT target HD 49434. This campaign was a preparatory step of the CoRoT satellite observations, which occurred between October 2007 and March 2008. Aims: With satellite data, detection of low-degree pulsation modes only is achievable, and, as no