In studies on intermediate- and high-resolution spectra of Type Ia supernovae (SNe Ia), some objects exhibit narrow Na I D absorptions often blueshifted with respect to the rest wavelength within the host galaxy. The absence of these in other SNe Ia may reflect that the explosions have different progenitors: blueshifted Na I D features might be

Using data from the extended Kepler mission in K2 Campaign 10, we identify two eclipsing binaries containing white dwarfs with cool companions that have extremely short orbital periods of only 71.2 min (SDSS J1205-0242, a.k.a. EPIC 201283111) and 72.5 min (SDSS J1231+0041, a.k.a. EPIC 248368963). Despite their short periods, both systems are

Context. Evolved stars with planets are crucial to understanding the dependency of the planet formation mechanism on the mass and metallicity of the parent star and to studying star-planet interactions. Aims: We present two evolved stars (HD 103485 and BD+03 2562) from the Tracking Advanced PlAnetary Systems (TAPAS) with HARPS-N project devoted to

Massive stars, at least ˜10 times more massive than the Sun, have two key properties that make them the main drivers of evolution of star clusters, galaxies, and the Universe as a whole. On the one hand, the outer layers of massive stars are so hot that they produce most of the ionizing ultraviolet radiation of galaxies; in fact, the first massive

We discuss the possibilities of exploiting the UV spectral using the J-PAS survey to disentangle young contributions from apparently old galaxies. We show that the feasibility of determining such young stellar components in early-type galaxies at moderately high redshift.

It is suggested that the chemical abundance trend with the condensation temperature, Tc , can be a signature of rocky planet formation or accretion. Recently, a strong Tc trend was reported in the Zetta Reticuli binary system (Saffe et al., 2016), where ζ2 Ret Ret shows a deficit of refractory elements relative to its companion (ζ1 Ret). This