More than 2000 stars distributed in the field of view of 35 planetary nebulae, and 31 stars from the spectral catalog of Jacoby et al. (1984, Cat. III/92) were observed with the LDSS2 (Low Dispersion Survey Spectrograph) at the William Herschel Telescope (WHT) on La Palma, Spain. (1 data file).

Context. The properties of variable stars can give independent constraints on the star formation history of the host galaxy, by determining the age and metallicity of the parent population. Aims: We investigate the pulsation properties of 84 Anomalous Cepheids (ACs) detected by the OGLE-III survey in the Large Magellanic Cloud (LMC), in order to

The surface deformation has been an essential parameter for the onset and evolution of the eruptive process of the island of El Hierro (October 2011) as well as for forecasting changes in seismic and volcanic activity during the crisis period. From GNSS-GPS observations the reactivation is early detected by analizing the change in the deformation

The uptake of anthropogenic CO2 by the oceans since the industrial revolution is considered to have considerably buffered atmospheric CO2 increases and thereby slow global climate change. However, the CO2 uptake is reducing the ocean's capacity to absorb future atmospheric CO2 which may lead to more pronounced climate forcings. We investigated the

Context. The mechanisms producing the diffuse radio emission in galaxy clusters, and in particular their connection with cluster mergers, are still debated. Aims: We seek to explore the internal dynamics of the cluster Abell 1758N, which has been shown to host a radio halo and two relics, and is known to be a merging bimodal cluster. Methods: Our

Asteroseismology with the Kepler space telescope is providing not only an improved characterization of exoplanets and their host stars, but also a new window on stellar structure and evolution for the large sample of solar-type stars in the field. We perform a uniform analysis of 22 of the brightest asteroseismic targets with the highest signal-to