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 top figure shows the first five atomic levels of Ca II. The bottom figure shows the linear polarization profiles calculated ignoring the discovered physical mechanism (dotted lines) and taking into account the possibility of zero-field dichroism (soli

    The linear polarization produced by scattering processes in the spectral lines of the IR triplet of Ca II can be observed near the edge of the solar disk. The cause of this polarization was considered a true enigma until the year 2003, in which IAC researchers could carry out sophisticated calculations based on the quantum theory of the spectral line polarization. In this way, they could demonstrate that the physical origin of the enigmatic polarization is the presence of "atomic polarization" in the lower levels of such spectral lines, which produces dichroism (i.e., selective absorption of

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  • Image of M82 (Subaru 8m telescope) showing galactic superwinds (on the left, in red). The box shows stellar superclouds identified by the IAC team in an image taken by the Hubble Space Telescope.

    Galactic superwinds present a filament-like structure, with strong X ray emissions, which could not be explained until now. Using hydrodynamic calculations, it has been possible to determine that this structure is caused by the autocollimation of the material that forms the galactic superwinds. The autocollimation is caused by the interaction of material escaping from stellar superclouds, compact groups of stars revealed by the HST in which intense stellar formation has given rise to at least 100 very massive and very luminous stars. This interaction also explains the X ray emission.

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  • Image of the comet 124P/Mrkos (up) and spectra (down) obtained in the near IR using the NICS spectrograph at the Telescopio Nazionale Galileo, Observatorio del Roque de los Muchachos (ORM).

    Observing the nucleus of a comet is difficult, because comets are normally active near the sun which means that their nuclei are hidden by their comae. 124P/Mrkos is a low-activity comet observed at 1.9 UA of the sun. The spectra of comets give us information not only about their composition, but also about the initial composition of the solar system. In this case the spectrum is very similar to that of the D- and P-type asteroids that typically populate the external part of the asteroid belt.

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