We have obtained two-dimensional velocity fields in the ionized gas of a set of eight double-barred galaxies, at high spatial and spectral resolution, using their Hα emission fields measured with a scanning Fabry-Perot spectrometer. Using the technique by which phase reversals in the non-circular motion indicate a radius of corotation, taking advantage of the high angular and velocity resolution we have obtained the corotation radii and the pattern speeds of both the major bar and the small central bar in each of the galaxies; there are few such measurements in the literature. Our results

We report on the near-infrared low-resolution spectroscopy and red optical (Z-band) photometry of seven proper-motion, very low-mass substellar member candidates of the Pleiades cluster with magnitudes in the interval J=17.5-20.8 and K=16.1-18.5 mag. Spectra were acquired for six objects with the LIRIS and NIRSPEC instruments mounted on the 4.2-m WHT and the 10-m Keck II telescopes. Z-band images of two of the faintest candidates were collected with ACAM/WHT. The new data confirm the low temperatures of all seven Pleiades candidates. From the imaging observations, we find extremely red Z-J

The measurement of the Rossiter-McLaughlin effect for transiting exoplanetsplaces constraints on the orientation of the orbital axis with respect to the stellar spin axis, which can shed light on the mechanisms shaping the orbital configuration of planetary systems. Here we present the interesting case of the Saturn-mass planet HAT-P-18b, which orbits one of the coolest stars for which the Rossiter-McLaughlin effect has been measured so far. We acquired a spectroscopic time-series, spanning a full transit, with the HARPS-N spectrograph mounted at the TNG telescope. The very precise radial

Happy New Year 2014 from the Instituto de Astrofísica de Canarias (IAC)

With the Canaricam instrument on the Gran Telescopio CANARIAS (GTC), a team of researchers known as ‘Los Piratas’ have caught a system of two galaxies fused together in collision, feeding two black holes at their centres

Astronomers at the IAC have discovered complex patterns of resonances in the discs of spiral galaxies not previously described by theories. Using the GHaFaS 2dimensional spectrometer they have measured the velocities of the density waves in the discs of over a hundred galaxies Within the discs of spiral galaxies there are waves which propagate concentrically in the form of spirals. This is somewhat similar to the waves on the surface of a lake, or the standing waves on the strings of a violin, or on the surface of a drum, to use a musical metaphor. These are the so-called “density waves”