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.

  • Out best-fit model for the rotation curve of the Milky Way. Asterisks represent the natural weighted radial bins derived from observational data by Sofue et al. (2009) with their associated error bars. The different lines represent the contribution of the
    The study of the disk rotation curve of our Galaxy at large distances provides an interesting scenario for us to test whether magnetic fields should be considered as a non-negligible dynamical ingredient. By assuming a bulge, an exponential disk for the stellar and gaseous distributions, and a dark halo and disk magnetic fields, we fit the rotation velocity of the Milky Way. In general, when the magnetic contribution is added to the dynamics, a better description of the rotation curve is obtained. Our main conclusion is that magnetic fields should be taken into account for the Milky Way
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  • GJ 1214b transit light curves obtained with GTC/OSIRIS tunable filters. In the bottom panels, the residuals of the curve fit are shown for each filter.
    Aims. The super-Earth planet GJ 1214b has recently been the focus of several studies, which use the transit spectroscopy technique to determine the nature of its atmosphere. Here, we focus on the Halpha line as a tool to further restrict the nature of GJ 1214b’s atmosphere. Methods. We used the Gran Telescopio Canarias (GTC) OSIRIS instrument to acquire narrow-band photometry with tunable filters. We were able to observe the primary transit of the super-Earth GJ 1214 in three bandpasses: two centered in the continuum around Halpha (653.5 nm and 662.0 nm) and one centered at the line core
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  • Stellar radial velocity curve for DY Cen. The deviations of observations to the computed fit for the best orbital parameters are shown in the bottom. The notation of the observations is shown in the inset.
    The stellar origin of the extremely hydrogen-deficient R Coronae Borealis (RCB) stars has remained a mystery for astronomers since their discovery more than two hundred years ago.  Two competing scenarios are commonly advocated. In the first one, a final helium shell flash occurs on a cooling white dwarf star or a very late thermal pulse is experienced by a post-AGB star. The second scenario involves the merger of two white dwarfs: a carbon–oxygen white dwarf accretes ahelium white dwarf. Evidence from the chemical compositions of RCB stars suggests that most are products of a merger
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  • Bar fraction distribution as function of the galaxy magnitudes (left panels) and masses (right panels). The bar fraction calculated using all the Hubble types (fT) and only the disk galaxies (fD) are plotted in the upper and bottom panels, respectively. T
    The effects that interactions produce on galaxy disks and how they modify the subsequent formation of bars need to be distinguished to fully understand the relationship between bars and environment. To this aim we derive the bar fraction in three different environments ranging from the field to Virgo and Coma Clusters, covering an unprecedentedly large range of galaxy luminosities (or, equivalently, stellar masses). We confirm that the fraction of barred galaxies strongly depends on galaxy luminosity. We also show that the difference between the bar fraction distributions as a function of
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