We have observed the B I 2497 A line to derive the boron abundances of two very metal-poor stars selected to help in tracing the origin and evolution of this element in the early Galaxy: BD +23 3130 and HD 84937. The observations were conducted using the Goddard High Resolution Spectrograph on board the Hubble Space Telescope. A very detailed

The (9) Be ii lambda 3131 Angstroms doublet has been observed in the solar-type stars 16 Cyg A & B and in the late G-type star rho (1) Cnc, to derive their beryllium abundances. 16 Cyg A & B show similar (solar) beryllium abundances while 16 Cyg B, which has been proposed to have a planetary companion of ~ 2 M_Jup, is known to be depleted in

We have obtained I-band photometry of the neutron star X-ray transient Aql X-1 during quiescence. We find a periodicity at 2.487 cycles d^-1, which we interpret as twice the orbital frequency (19.30+/-0.05 h). Folding the data on the orbital period, we model the light-curve variations as the ellipsoidal modulation of the secondary star. We

From optical data of Q0957+561 for 1995/1996 seasons (in the g band) and 1996/1997 seasons (in the R band) they are derived upper limits on the amplitude of the rapid microlensing fluctuations of 0.07 mag and 0.05 mag, respectively. The photometry in the R band (1996/1997 seasons) was taken at Teide Observatory (IAC-80 Telescope), Instituto de

ODIN is an international consortium constituted to design and build a first-light multi-purpose optical intermediate dispersion spectrograph for the Gran Telescopio Canarias (GTC, 10-m) to be installed at the Observatorio del Roque de los Muchachos (La Palma). This instrument should fulfill an important fraction of the needs of the Spanish

We present spectroscopic observations of the LBV candidate WRA 751 taken at different epochs during the period 1989-1995. These observations are used to monitor the temporal evolution of the spectrum over the last few years. In addition, we identify most of the emission and absorption features in the spectral range 4100-9250 Angstroms and obtain a