News

This section includes scientific and technological news from the IAC and its Observatories, as well as press releases on scientific and technological results, astronomical events, educational projects, outreach activities and institutional events.

  • Figure caption: The transmission spectrum of Jupiter during the penumbra (a) and the umbra (b)phases. Gray shaded regions mark the deeply absorbed telluric bands of H2O, which cannot be observed from the ground. The locations of the major CH4 absorption b
    Currently, the analysis of transmission spectra is the most successful technique to probe the chemical composition of exoplanet atmospheres. However, the accuracy of these measurements is constrained by observational limitations and the diversity of possible atmospheric compositions. Here, we show the UV-VIS-IR transmission spectrum of Jupiter as if it were a transiting exoplanet, obtained by observing one of its satellites, Ganymede, while passing through Jupiter's shadow, i.e., during a solar eclipse from Ganymede. The spectrum shows strong extinction due to the presence of clouds
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  • Each point represents one individual measurement of the baryon fraction relative to the Universal baryon content, at a given distance around BOSS galaxies. Red points correspond to detections, positive signal with its corresponding error bar, whereas gree
    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
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  • Caption: Artist illustration of the central core of the planetary nebula Henize 2-428. Stars are not to scale. Credit: Gabriel Pérez, SMM (IAC).
    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
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  • Figure caption. Left panel: Image of the planet at 100 AU from the dwarf star VHS 1256.This false colour image has been put together from images in the Y J and K bands takenwith the VISTA telescope of the European Southern Observatory, in the VISTA Hemisp
    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
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  • Evolution of the volume occupied by the ejecta (left panels) and the shock top pole velocity (right panels). Panels (a) and (b), (c) and (d), (e) and (f) show the results of the calculations when the explosion occurs at Zoff = 0 pc, 1 pc, and 2 pc from th
    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
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  • Figure caption: Profiles of the broad 4428 Å band (left panel) and of the 5780 Å feature (right panel) towards Tc 1 central star (black) and average of two sight lines to the nebular position on either side of the nebula. In both panels, the dashed blue l
    Identification of the carriers of the diffuse interstellar bands (DIBs) has been very elusive since the beginning of the last century. Differentcomplex carbon-based molecules - e.g., carbon chains, polycyclicaromatic hydrocarbons (PAHs), and fullerenes - have been proposed asDIB's carriers. If the DIBs arise from large gas phase molecules, such as PAHs and fullerenes, then they are also expected to be present in other carbon-rich space environments like circumstellar shells around evolved stars. Diffuse circumstellar bands (DCBs) in absorption have been unsuccessfully studied for more than
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