Comet Tempel 1 was observed before and after the impact with the echelle spectrograph SARG on the TNG telescope in La Palma. We are cataloguing the lines visible in the spectra and comparing the spectra between them.

We present U and B galaxy differential number counts from a field of ~900 arcmin2, based on GOYA Survey imaging of the HST Groth-Westphal strip. Source detection efficiency corrections as a function of the object size have been applied. A variation of the half-exposure image method has been devised to identify and remove spurious detections

Non-baryonic Dark Matter (DM) appears in galaxies and other cosmic structures when and only when the acceleration of gravity, as computed considering only baryons, goes below a well defined value a0 = 1.2 × 10-8 cm s-2. This fact is extremely important and suggestive of the possibility of a breakdown of Newton's law of gravity (or inertia) below a0

The Leo group elliptical NGC 3379 is one of the few normal elliptical galaxies close enough to make possible observations of resolved stellar populations, deep globular cluster (GC) photometry and high signal-to-noise ratio GC spectra. We have obtained Gemini/GMOS spectra for 22 GCs associated with NGC 3379. We derive ages, metallicities and α

Las enanas marrones son el puente entre las estrellas menos masivas y los planetas gigantes. Más de diez años después de su descubrimiento.. Hemos pretendido realizar una determinación precisa de la función de masa en un cúmulo estelar muy joven e idóneo por su distancia y baja extinción, sigma Orionis, para explorar un rango de masas hasta el

We present a study of the young (30-100 Myr) open cluster IC 4665 with the aim to determine the shape of the mass function well into the brown dwarf regime. We photometrically select 691 low-mass stellar and 94 brown dwarf candidate members over an area of 3.82 square degrees centred on the cluster. K-band follow-up photometry and Two-Micron All