We have obtained low-resolution optical spectra of three faint brown dwarf candidates in the Pleiades open cluster. The objects observed are Roque 12 (I_C=18.5), Roque 5 (I_C=19.7), and Roque 25 (I_C=21.2). The spectrum of Roque 25 does not show the strong TiO band heads that characterize the optical spectra of M-type stars, but molecular bands of

High resolution H alpha and white light observation of the birth of 73 active regions (AR) were used to check models of sunspots. It is concluded that large AR result from the emergence of a compact and twisted flux rope, while the small ones are produced by the clustering of flux tubes by supergranular motions.

In this article we demonstrate that PKS J1037-2705 has a weak accretion flow luminosity, well below the Seyfert 1/QSO dividing line, weak broad emission lines (BELs), and moderately powerful FR II extended radio emission. It is one of the few documented examples of a broad-line object in which the time-averaged jet kinetic luminosity, Q, is larger

Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific

Aimed at understanding the evolution of galaxies in clusters, the GLACE survey is mapping a set of optical lines ([OII]3727, [OIII]5007, Hβ and Hα/[NII] when possible) in several galaxy clusters at z ˜ 0.40, 0.63 and 0.86, using the Tuneable Filters (TF) of the OSIRIS instrument (Cepa et al. 2005) at the 10.4 m GTC telescope. This study will

We study the geometry of the active galactic nucleus (AGN) obscurer in IRAS 09104+4109, an IR-luminous, radio-intermediate FR-I source at z = 0.442, using infrared data from Spitzer and Herschel, X-ray data from NuSTAR, Swift, Suzaku, and Chandra, and an optical spectrum from Palomar. The infrared data imply a total rest-frame 1–1000 μm luminosity