We use Atacama Large Millimetre Array and Jansky Very Large Array observations of the galaxy cluster Cl J1449+0856 at z = 1.99, in order to study how dust-obscured star formation, interstellar medium content, and active galactic nuclei activity are linked to environment and galaxy interactions during the crucial phase of high-z cluster assembly. We

Emission lines from metals offer one of the most promising ways to detect the elusive warm-hot intergalactic medium (WHIM; 105 < T < 107K), which is thought to contain a substantial fraction of the baryons in the low-redshift Universe. We present predictions for the soft X-ray line emission from the WHIM using a subset of cosmological simulations

Spectroscopic data of two relatively [O III]-luminous planetary nebulae (PNe) have been obtained with the 10.4 m Gran Telescopio Canarias. M174 and M2496 are each ~1° from the center of M31 along opposite sides of its minor axis. The ensemble of these 2 distant PNe plus 16 similarly luminous outer-disk PNe published previously by Kwitter et al

Dependence of phenomenological properties of Cepheids on the heavy element abundance is studied. It is found that the amplitude of the pulsation depends on the metallicity of the stellar atmosphere.

We have obtained metallicity estimates for a sample of A/F-type stars that appear to be members of the recently discovered Monoceros Stream. This sample of candidate main-sequence turn-off stars was chosen from the Sloan Digitized Sky Survey southern program spectra. The average metallicity, = -1.37 ± 0.04, is consistent with the abundance of six

We summarize the state of the art of a program of UV observations from space of meteor phenomena, a secondary objective of the JEM-EUSO international collaboration. Our preliminary analysis indicates that JEM-EUSO, taking advantage of its large FOV and good sensitivity, should be able to detect meteors down to absolute magnitude close to 7. This