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.

  • Variación del vector campo magnético en espículas solares (de izq. a der. intensidad, inclinación y azimut del campo) con la altura sobre el limbo solar, inferido mediante el código HAZEL
    Proving the magnetic configuration of solar spicules has hitherto been difficult due to the lack of spatial resolution and image stability during off-limb ground-based observations.  We report spectropolarimetric observations of spicules taken in the He I 1083 nm spectral region with the Tenerife Infrared Polarimeter II at the German Vacuum Tower Telescope at the Teide Observatory (Tenerife; Canary Islands; Spain). The data provide the variation with geometrical height of the Stokes I, Q, U, and V profiles whose encoded information allows the determination of the magnetic field vector by
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  • The hypothesis of a universal initial mass function (IMF) - motivated by observations in nearby stellar systems - has been recently challenged by the discovery of a systematic variation of the IMF with the centralvelocity dispersion, σ, of early-type galaxies (ETGs), towards an excessof low-mass stars in high-σ galaxies. This trend has been derived so farfrom integrated spectra, and remains unexplained at present. To testwhether such trend depends on the local properties within a galaxy, we have obtained new, extremely deep, spectroscopic data, for three nearby ETGs, two galaxies with high σ
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  • Schematic picture of a tornado-like magnetic structure. Solid lines are the three-dimensional representation of the magnetic field lines. Dashed lines are thepoloidal field lines in the azimuthal plane.
    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on
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  • 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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