After the discovery of Proxima Centauri b in 2016, we observed the system with the Spitzer Space Telescope to look for transits. We confirmed that the planet does not transit. However, we observed three asymmetric, periodic, comet-like events. Unfortunately, we now understand these events to be systematic effects due to telescope vibration, which

Context. Fossil groups (FGs) are galaxy aggregates with an extended and luminous X-ray halo, which are dominated by a very massive early-type galaxy and lack of L∗ objects. FGs are indeed characterized by a large magnitude gap between their central and surrounding galaxies. This is explained by either speculating that FGs are failed groups that

Context. Major mergers are popularly considered too destructive to produce the relaxed regular structures and the morphological inner components (ICs) usually observed in lenticular (S0) galaxies. Aims: We aim to test if major mergers can produce remnants with realistic S0 morphologies. Methods: We have selected a sample of relaxed discy remnants

NASA's OSIRIS-REx and JAXA's Hayabusa2 sample-return missions are currently on their way to encounter primitive near-Earth asteroids (101955) Bennu and (162173) Ryugu, respectively. Spectral and dynamical evidence indicates that these near-Earth asteroids originated in the inner part of the main belt. There are several primitive collisional

We study the evolved stellar population of the Local Group galaxy IC10, with the aim of characterizing the individual sources observed and to derive global information on the galaxy, primarily the star-formation history and the dust production rate. To this aim, we use evolutionary sequences of low- and intermediate-mass (M 8 M_{⊙}) stars, evolved

Context. Thorium hollow cathode lamps (HCLs) are used as frequency calibrators for many high resolution astronomical spectrographs, some of which aim for Doppler precision at the 1 m s-1 level. Aims: We aim to determine the most suitable combination of elements (Th or U, Ar or Ne) for wavelength calibration of astronomical spectrographs, to