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.

  • The Stokes profiles of the Mg II k line calculated in a semi-empirical model of the solar atmosphere, in the absence (black curves) and in the presence (coloured curves) of a horizontal magnetic field with zero azimuth (i.e., on the plane defined by the l
    The polarization of the Mg II k line at 279.5 nm encodes valuable information on the magnetic field of the upper solar chromosphere, where this strong resonance line originates. We have developed a novel radiative transfer code which allows us to account for scattering polarization and the Hanle and Zeeman effects, as well as partial frequency redistribution (PRD) phenomena (i.e., correlation effects between the incoming and outgoing photons in the scattering events). This non-LTE code, which treats the atomic system and the polarized radiation field quantum-mechanically, has been applied to
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  • Distributions of 830 galaxies in the BOSS Great Wall (BGW). The colour scale shows the local environmental density in terms of mean densities for each galaxy. With a total diameter of 271 h-1 Mpc and average redshift of 0.47 for its sources, this superclu
    Superclusters are the largest over-dense, relatively isolated systems in the cosmic web. They provide us invaluable information about the large-scale structure formation at different cosmic epochs, as well as they are excellent places for understanding galaxy evolution in detail. Thanks to the new SDSS-III data, we can extend our knowledge of superclusters to the redshift range above z=0.4. We used data from the twelfth data release of the Sloan Digital Sky Survey (SDSS). Using a sample of more than 500,000 galaxies up to z~0.8, we reconstructed the large-scale luminosity-density field and
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  • Average, normalized spectra corresponding to days 9 to 11 of the outburst. During this period the X-ray, optical and radio fluxes dropped by three orders of magnitude from the outburst peak. The spectra are very rich in emission lines that, while typical
    V404 Cygni is a black hole within a binary system where a black hole of around 10 times the mass of the Sun is swallowing material from a very nearby star. During this process material falls onto the black hole and forms an accretion disc, whose hotter, innermost zones emit in X-rays. On June 2015 V404 Cygni went into outburst after a quiescence of over 25 years. During this period its brightness increased on million fold in a few days, becoming the brightest X-ray source in the sky. Optical observations carried out with the GTC 10.4m discovered the presence of a wind of cold material, which
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  • Upper panel: Example of a spectrum contained in the Fabry-Pérot data where we detect three pairs of emission peaks symmetrically spaced with the emission of the H ii region, which correspond to the presence of three expanding shells.Lower panel: Expansion
    Using a specialized technique sensitive to the presence of expanding ionized gas, we have detected a set of three concentric expanding shells in an H ii region in the nearby spiral galaxy M33. The detection was done using Fabry-Pérot spectroscopy, which allows us to map the ionized gas emission line Hα with exceptional precision in the spatial and spectral coordinates. We also took long-slit spectra of colisionally excited emission lines, which showed that the shells are likely originated from supernova explosions. Using the flux and the kinematics we estimated the kinetic energy in the
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  • Wide angle view from the Teide Observatory towards the east. Above the horizon you can see the planet Venus, an a little higher up and to the left of Venus is comet Catalina (C/2013 US10). The lights and villages are on Grand Canary. J.C. Casado-staryeart
    Several telescopes at the Teide Observatory (IAC) followed comet Catalina with the aim of characterizing its orbit dynamically. It should be possible to see the central zone of the comet with the naked eye, but to see details you would need binoculars.
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