Its latest data release contains information about 470 million stars and galaxies

We obtained GALEX FUV, NUV, and Spitzer/IRAC 3.6 µm photometry for >2000 galaxies, available for 90% of the S4G sample. We find a very tight "GALEX Blue Sequence (GBS)" in the (FUV − NUV) versus (NUV − [3.6]) color-color diagram which is populated by irregular and spiral galaxies, and is mainly driven by changes in the formation timescale (τ ) and a degeneracy between τ and dust reddening. The tightness of the GBS provides an unprecedented way of identifying starforming galaxies and objects that are just evolving to (or from) what we call the "GALEX Green Valley (GGV)". At the red end of the

Our arguments deal with the early evolution of Galactic globular clusters and show why only a few of the supernovae products were retained within globular clusters and only in the most massive cases (M>106 solar masses) while less massive clusters were not contaminated at all by supernovae. Here we show that supernova blast waves evolving in a steep density gradient undergo blowout and end up discharging their energy and metals into the medium surrounding the clusters. This inhibits the dispersal and the contamination of the gas left over from a first stellar generation. Only the ejecta from

Identification of the carriers of the diffuse interstellar bands (DIBs) has been very elusive since the beginning of the last century. Differentcomplex carbon-based molecules - e.g., carbon chains, polycyclicaromatic hydrocarbons (PAHs), and fullerenes - have been proposed asDIB's carriers. If the DIBs arise from large gas phase molecules, such as PAHs and fullerenes, then they are also expected to be present in other carbon-rich space environments like circumstellar shells around evolved stars. Diffuse circumstellar bands (DCBs) in absorption have been unsuccessfully studied for more than

We explore the stellar initial mass function (IMF) of a sample of 49massive quiescent galaxies (MQGs) at 0.9

We present multilevel radiative transfer modeling of the scattering polarization observed in the solar O I infrared triplet around 777 nm. We demonstrate that the scattering polarization pattern observed on the solar disk forms in the chromosphere, far above the photospheric region where the bulk of the emergent intensity profiles originate. We investigate the sensitivity of the polarization pattern to the thermal structure of the solar atmosphere and to the presence of weak magnetic fields (0.01 –100 G) through the Hanle effect, showing that the scattering polarization signals of the oxygen