We use high-resolution (~0farcs1) F814W Advanced Camera for Surveys (ACS) images from the Hubble Space Telescope ACS Treasury survey of the Coma cluster at z ~ 0.02 to study bars in massive disk galaxies (S0s), as well as low-mass dwarf galaxies in the core of the Coma cluster, the densest environment in the nearby universe. Our study helps to

We investigate the potential of submm-mm and submm-mm-radio photometric redshifts using a sample of mm-selected sources as seen at 250, 350 and 500μm by the SPIRE instrument on Herschel. From a sample of 63 previously identified mm sources with reliable radio identifications in the Great Observatories Origins Deep Survey North and Lockman Hole

We report on the photospheric evolution of an intermediate-scale (≈4 Mm footpoint separation) magnetic bipole, from emergence to decay, observed in the quiet Sun at high spatial (0farcs3) and temporal (33 s) resolution. The observations were acquired by the Imaging Magnetograph Experiment imaging magnetograph during the first science flight of the

Observations of quasar absorption-line systems reveal that the z= 3 intergalactic medium (IGM) is polluted by heavy elements down to H I optical depths τH I≪ 10. What is not yet clear, however, is what fraction of the volume needs to be enriched by metals and whether it suffices to enrich only regions close to galaxies in order to reproduce the

EMPhaSSiS is a photometric and spectroscopic survey of the disk of the Milky Way. The survey covers 33 fields in the 3rd quadrant of the Milky Way and probes every ten degrees in Galactic Longitude between l = 180∘ - 280∘ and at Galactic Latitudes of b = -20∘, - 30∘ and - 40∘. Each field is observed in four filters, U, B, V and R, reaching depths

We present a chemical-composition analysis of 77 red-giant stars in Omega Centauri. We have measured abundances for carbon and nitrogen, and combined our results with abundances of O, Na, La, and Fe that we determined in our previous work. Our aim is to better understand the peculiar chemical-enrichment history of this cluster by studying how the