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.

  • GTC light curve of PG1144+005 (top) and its Fourier amplitude spectrum showing the detected pulsation periods (bottom).
    Up to 98% of all single stars will eventually become white dwarfs - stars that link the history and future evolution of the Galaxy, and whose previous evolution is engraved in their interiors. Those interiors can be studied using asteroseismology, utilizing stellar pulsations as seismic waves. The pulsational instability strips of DA and DB white dwarf stars are pure, allowing for the important generalization that their interior structure represents that of all DA and DB white dwarfs. This is not the case for the hottest pulsating white dwarfs, the GW Vir stars: only about 50% of white
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  • Top: final transmission spectrum and retrieved models for HAT-P-65b. The white circles refer to the data. The blue line and shading show the results from the full retrieval, while the red line and shading from the K-muted retrieval. Bottom: retrieved temperature-pressure (T-P) profiles and mass fractions for the full retrieval (left two) and K-muted retrieval (right two), respectively.
    We present the low-resolution transmission spectra of the puffy hot Jupiter HAT-P-65b (0.53 MJup, 1.89 RJup, Teq = 1930 K), based on two transits observed using the OSIRIS spectrograph on the 10.4 m Gran Telescopio CANARIAS. The transmission spectra of the two nights are consistent, covering the wavelength range 517–938 nm and consisting of mostly 5 nm spectral bins. We perform equilibrium-chemistry spectral retrieval analyses on the jointly fitted transmission spectrum and obtain an equilibrium temperature of 1645 (-244+255) K and a cloud coverage of 36 (-17+23) %, revealing a relatively
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  • Optical spectrum from the VHE gamma-ray blazar S4 0954+65. The detection of the emission lines allows us to firmly establish the redshift and the characteristics of the source.
    The most extreme electromagnetic radiation that can be observed is known as very high energy gamma rays (VHE, E>100 GeV). It is the last window open to the Universe, thanks to the development of the Cherenkov telescopes. The extragalactic VHE sky is still nowadays vastly unexplored, only composed of around 80 known sources. The great majority of them are classified as blazars, a type of Active Galactic Nuclei (AGN) whose relativistic jets point in the direction of the Earth boosting their emission. While the observation of the gamma-ray emission is crucial to understand the extreme physical
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  • Spectral energy distribution from radio to VHE gamma rays. For the first time a narrow spectral feature is detected in the VHE band. The proposed theoretical emission model is represented by the red curve (taken from Acciari et al. 2020, A&A, 637, A86).
    Blazars, Active Galactic Nuclei (AGN) whose relativistic jets point in the direction of the Earth, dominate the VHE (VHE, E>100 GeV) gamma-ray extragalactic sky. One of the most famous archetypical VHE gamma-ray emitters is the blazar Markarian 501 (Mrk 501). During July 2014, the source displayed a strong flare detected across all wavelengths from VHE to the optical band. In particular, it is especially interesting that the source reached the maximum flux and harder spectrum measured in the X-ray band, compatible with the most extreme historical flare from this source. On 2014 July 19
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  • The lines of flow of the magnetic field detected with SOFIA are shown superposed on an image of the Whirlpool Galaxy (M51), by NASA’s Hubble Space Telescope. Credits: NASA, the SOFIA science team, A. Borlaff; NASA, ESA, S. Beckwith (STScI) and the Hubble Heritage Team (STScI/AURA).
    There is a force hidden deep inside galaxies: magnetic fields. Invisible to conventional telescopes, they are a factor in galaxy evolution, regulating the formation of new stars and helping to drive intragalatic gas towards their central supermassive black hole.
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  • Image of the galaxy cluster Abell 370, one of the regions of the sky observed in the SHARDS Frontier Fields project. This is the deepest image ever taken to detect galaxies with emission lines, which are actively forming stars. The centre of the cluster is in the upper right of the image. In the same area, you can see gravitationally amplified galaxies, some of them showing highly deformed and lengthened morphologies, known as arcs. Credit: GRANTECAN
    One of the most interesting questions for astrophysicists for the past few decades is how and when did the first galaxies form. One of the possible answers to “how” is that star formation in the first galaxies took place at a steady rate, building up a system with increasing mass. Another possibility is that the formation was more violent and discontinuous, with intense bursts of star formation, on short timescales, triggered by events such as galaxy mergers and strong concentrations of gas.
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