The total baryon content in the Universe is a well-defined quantity, in addition to being one of the most important cosmological parameters. A variety of observations (CMB, Ly-alpha forest, Big Bang nucleosynthesis) indicate that all baryons amount to around 4% of the total matter-energy content of the Universe. However, in the local Universe the contribution of all the observed components represents around 2% of the total. Therefore, half of the baryons in the local Universe remain elusive. In this article we have presented measurements of the kinematic Sunyaev-Zel’dovich effect in Planck

The planetary nebula (PN) stage is the ultimate fate of stars with mass 1 to 8 solar masses (M⊙). The origin of their complex morphologies is poorly understood, although several mechanisms involving binary interaction have been proposed. In close binary systems, the orbital separation is short enough for the primary star to overfill its Roche lobe as it expands during the Asymptotic Giant Branch (AGB) phase. The excess material ends up forming a common-envelope (CE) surrounding both stars. Drag forces would then result in the envelope being ejected into a bipolar PN whose equator is

In a search for common proper motion companions using the VISTA Hemisphere Survey (VHS) and the 2MASS catalogs we have identi fied a very red (J-Ks = 2.47 mag) late-L dwarf companion of a previously unrecognized M dwarf VHSJ125601.92-125723.9 (hereafter VHS1256-1257), located at a projected angular separation of 8.06"+/-0.03". In this work we present a suite of astrometric, photometric, and spectroscopic observations of this new pair in an effort to confirm the companionship and characterize the components. From low-resolution (R_130-600) optical and near-infrared spectroscopy we classi fied

Our arguments deal with the early evolution of Galactic globular clusters and show why only a few of the supernovae products were retained within globular clusters and only in the most massive cases (M>106 solar masses) while less massive clusters were not contaminated at all by supernovae. Here we show that supernova blast waves evolving in a steep density gradient undergo blowout and end up discharging their energy and metals into the medium surrounding the clusters. This inhibits the dispersal and the contamination of the gas left over from a first stellar generation. Only the ejecta from

El director del IAC, Rafael Rebolo, junto con otros representantes de esta institución asistieron hoy a la Jornada "Oportunidades financieras y tecnológicas para proyectos empresariales de I+D en el campo de la Astrofísica en Canarias"

A study of the binary system “MY Camelopardalis” published in the journal Astronomy & Astrophysics, shows that the most massive stars are formed by the merging of other smaller stars, as theoretical models predicted.