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.

  • (a) Visible spectra of DA14 obtained with CAFOS at the 2.2m CAHA telescope (black) and OSIRIS at GTC (red). Filled circles are the reflectance R values obtained from the fotometry. (b) Same as the top panel, but adding the R values for the near-infrared.
    Near-Earth asteroid 2012 DA 14 made its closest approach on February 15, 2013, when it passed at a distance of 27,700 km from the Earth’s surface. It was the first time an asteroid of moderate size was predicted to approach that close to the Earth, becoming bright enough to permit a detailed study from ground-based telescopes. Asteroid 2012 DA 14 was poorly characterized before its closest approach. The main objective of this work was to obtain new and valuable data to better understand its physical properties, and to evaluate the effects of such a close approach on the object. We acquired
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  • Fig. 1: Top panel: orbital phase shift at the time of the inferior conjunction (orbital phase 0), Tn, of the secondary star in the BHXB XTE J1118+480 versus the orbital cycle number, n, folded on the best-fit parabolic fit. The error bars give the observa
    We present new 10.4 m-GTC/OSIRIS spectroscopic observations of the black hole X-ray binary XTE J1118+480 that confirm the orbital period decay at (dP/dt) = −1.90 ± 0.57 ms yr −1. This corresponds to a period change of −0.88 ± 0.27 μs per orbital cycle. We have also collected observations of the black hole X-ray binary A0620–00 to derive an orbital period derivative of (dP/dt)= −0.60 ± 0.08 ms yr −1 (−0.53 ± 0.07 μs/cycle). Angular momentum losses due to gravitational radiation are unable to explain these large orbital decays in these two short- period black hole binaries. The orbital period
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  • Image en banda z of a Y dwarf, WISE1217+1626. The red circle indicates the position of the Y dwarf on the GTC image whereas the black circle denominates the position of the discovery image.
    The aim of the project is to contribute to the characterisation of the spectral energy distribution of the coolest brown dwarfs discovered to date, the Y dwarfs.We obtained z-band far-red imaging for six Y dwarfs and a T9+Y0 binary with the OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) instrument on the 10.4-m Gran Telescopio de Canarias (GTC).We detect five of the seven known Y dwarfs in the z-band, infer theioptical-to-infrared colours, and measure their proper motions. We find a higher dispersion in the z-J and z-H colours of Y0 dwarfs than in T dwarfs
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  • Constraints on stellar rotation and planet mass. The dark-red and light-red regions are the 1-σ and 2- σ seismic constraints on stellar rotation in the plane (Ω / ΩSun) - (sin i), where Ω is the bulk angular velocity, ΩSun / 2 π= 0.424 μHz is the solar Ca
    Rotation is thought to drive cyclic magnetic activity in the Sun and Sun-like stars. Stellar dynamos, however, are poorly understood owing to the scarcity of observations of rotation and magnetic fields in stars. Here, inferences are drawn on the internal rotation of a distant Sun-like star by studying its global modes of oscillation. We report asteroseismic constraints imposed on the rotation rate and the inclination of the spin axis of the Sun-like star HD52265, a CoRoT prime target known to host a planetary companion. These seismic inferences are remarkably consistent with an independent
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  • VIMOS-IFU spectroscopy of the shock front in the remnant of SN 1006. The top-left panel shows a composite imageof the full remnant (≈30′ in diameter), combining data from the Very Large Array and Green Bank Telescope (red;NRAO/AUI/NSF/GBT/VLA/Dyer, Maddal
    Supernova remnants are among the most spectacular examples of astrophysical pistons in our cosmic neighborhood. The gas expelled by the supernova explosion is launched with velocities ∼1000 km/s into the ambient, tenuous interstellar medium, producing shocks that excite hydrogen lines. We have used an optical integral-field spectrograph to obtain high-resolution spatial-spectral maps that allow us to study in detail the shocks in the northwestern rim of supernova 1006. The two-component Halpha line is detected at 133 sky locations. Variations in the broad line widths and the broad-to-narrow
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  • High-resolution optical spectra (in black) and best model fits (in red) in the Li I 6708 Å region for the AGB stars RU Ari, R Cen, SV Cas, and RU Cyg. The derived Li (in the usual scale log N(X) + 12) are indicated. Synthetic spectra obtained for Li abund
    Low− and intermediate-mass (0.8 < M < 8 solar mass) stars constitute most of the stars in the Universe and they end their lives with a phase of strong mass loss and thermal pulses (TP) on the Asymptotic Giant Branch (AGB). AGB stars are fundamental to understand the chemical evolution of galaxies because they are one of the main contributors to the chemical enrichment (e.g. C, N, Li, F, and s-process elements) of the interstellar medium where new stars and planets born. In particular, the more massive (>4-5 solar mass) AGB stars experience Hot Bottom Burning (HBB), i.e. proton-capture
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