This paper presents the results of a detailed X-ray spectral analysis of a sample of 123 X-ray sources detected with XMM-Newton in the Lockman Hole field. This is the deepest observation carried out with XMM-Newton with more that 600 ks of good EPIC-pn data. We have spectra with good signal to noise (>500 source counts) for all objects down to 0.2

In this paper we review some recent detections of wide binary brown dwarf systems and discuss them in the context of the multiplicity properties of very low-mass stars and brown dwarfs.

This project addresses the reasons that may motivate efforts to popularize astronomy. Data relevant to this research question were collected by means of focus groups involving professional astronomers at a large Spanish research institute, followed by a questionnaire to the same group of people. The data showed that the main driver for astronomy

We present mid-IR observations of a sample of very low-mass stars and brown dwarfs in the Upper Scorpius association. The main goal of these observations is to derive the disk frequency and the disk properties of the sample in order to shed light on brown dwarf formation theories. The observations have been performed with VISIR at the Very Large

The Virgo Intra-Cluster Stars (VICS) project is a 37 orbit HST program to study the stellar constituents of Virgo's intracluster space. The survey is centered on a region of space 180 kpc (projected) from the nearest major galaxy (M 86), at a location where the underlying cluster surface brightness is μ V ˜ 27.5 ± 0.5. The data include extremely

We report the discovery of a very low-luminosity (MV -10) dwarf galaxy in the Virgo Cluster within the ACS field of the VICS Project (Ciardullo et al.). The galaxy, which is ˜ 1 kpc in extent, is clearly resolved into stars, and provides us with the first direct look at the stellar population of a low-luminosity system in a galaxy cluster. A F606W