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.

  • Colour-magnitude diagram (a form of the Hertzsprung-Russell diagram) of the globular cluster M13. The AGB stars of the first and second generations are shown in blue and red, respectively, while the less evolved red giants are shown in green. Crédits: ada
    Galactic globular clusters (GCs) are known to host multiple stellar populations: a first generation (FG) with a chemical pattern typical of halo field stars and a second generation (SG) enriched in Na and Al and depleted in O and Mg. Both stellar generations are found at different evolutionary stages (e.g., the main-sequence turnoff, the subgiant branch, and the red giant branch (RGB)). The non-detection of SG asymptotic giant branch (AGB) stars in several metal-poor ([Fe/H] < ‑1) GCs suggests that not all SG stars ascend the AGB phase, and that failed AGB stars may be very common in metal
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  • Figure caption: NEA discovery stack images. The field of view (FOV) is 2 arcmin x 2 arcmin in normal sky orientation. 2014 OL339 could be barely seen in the upper side, while for EUHT400 we include only the last four of the available six images.
    Since 2006, the European Near Earth Asteroids Research (EURONEAR)project has been contributing to the research of near-Earth asteroids (NEAs) within a European network. One of the main aims is the amelioration of the orbits of NEAs, and starting in 2014 February we focus on the recovery of one-opposition NEAs using the Isaac Newton Telescope (INT) in La Palma in override mode. As a part of this NEA recovery project, since 2014 June EURONEAR serendipitously started to discover and secure the first NEAs from La Palma using the INT, and thanks to the teamwork including amateurs and students who
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  • 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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