Linares et al. obtained quasi-simultaneous g΄-, r΄- and i΄-band light curves and an absorption-line radial velocity curve of the secondary star in the redback system 3FGL J0212.1+5320. The light curves showed two maxima and minima primarily due to the secondary star's ellipsoidal modulation, but with unequal maxima and minima. We fit these light

The warm star sample (7000 Teff 10,000 K) in SDSS is comprised of field horizontal branch (FHB) stars and a large number of blue straggler (BS) stars. Because these stars have a higher intrinsic luminosity than their cooler, turnoff and main-sequence counterparts, they are an ideal sample for probing both the global properties of the thick disk

We present an overview of the life-cycle of the observing proposals to the GTC and the software tools designed to help the astronomers to create and submit these proposals for evaluation and execution.

The topic of brown dwarf and extrasolar planet research with the GTC and the LMT was discussed during a half day workshop at Universidad Nacional Autonoma de Mexico. This paper summarizes the contributions presented at that Workshop plus additional contributions from members of the Spanish Network for extrasolar planets. Specific observational

pt5m is a 0.5 m robotic telescope located on the roof of the 4.2 m William Herschel Telescope (WHT) building, at the Roque de los Muchachos Observatory, La Palma. Using a five-position filter wheel and CCD detector, and bespoke control software, pt5m provides a high-quality robotic observing facility. The telescope first began robotic observing in

New pulsation modes in two delta Scuti stars of Praesepe cluster, BQ and BW Cnc, have been detected during the STEPHI VI campaign in 1995. In particular, 3 frequencies for BQ Cnc and 9 frequencies for BW Cnc have been found above a 99% confidence level. The possibility of the presence of a g-mode present in BQ Cnc is discussed, considering its