Context: The influence of binarity on the late stages of stellar evolution remains an open issue. Aims: While the first binary post-AGB stars were serendipitously discovered, the distinct characteristics of their spectral energy distribution (SED) allowed us to launch a more systematic search for binaries. We selected post-AGB objects, which

We have performed power spectral analysis of surface temperatures, velocities, and magnetic fields, using spectropolarimetric data taken with the Hinode Solar Optical Telescope. When we make power spectra in a field of view covering the supergranular scale, kinetic and thermal power spectra have a prominent peak at the granular scale while the

Context. For over 12 yr, we have carried out a precise radial velocity (RV) survey of a sample of 373 G- and K-giant stars using the Hamilton Échelle Spectrograph at the Lick Observatory. There are, among others, a number of multiple planetary systems in our sample as well as several planetary candidates in stellar binaries. Aims: We aim at

The work reported here demonstrates that it is possible to accurately determine surface gravities of δ Scuti (δ Sct) stars using the frequency content from high-precision photometry and a measurement of the parallax. Using a sample of 10 eclipsing binary systems with a δ Sct component and the unique δ Sct star discovered with a transiting planet

Two sample-return missions, OSIRIS-REx and Hayabusa 2, have just arrived at primitive near-Earth asteroids (NEAs) (101955) Bennu and (162173) Ryugu, and it is of interest to predict the effects of space weathering on their surfaces. Most spacecraft-accessible NEAs originate in the inner asteroid belt, and these two sample-return targets most likely

The 10m Gran Telescopio Canarias (GTC) is currently being installed in the Observatorio del Roque de los Muchachos (ORM) on the island of La Palma. An adaptive optics (AO) system will be installed at one of the Nasmyth foci of the telescope within a year of the telescope being commissioned. The preliminary design of the adaptive optics system is