J004457+4123 (Sharov 21): not a remarkable nova in M31 but a background quasar with a spectacular UV flare

J0454-0309: Evidence for a strong lensing fossil group falling into a poor galaxy cluster

J1145-0033 - the most distant giant radio source?

J16021+3326: New Multi-Frequency Observations of a Complex Source

Jeans Instability of Palomar 5's Tidal Tail

Jet opening angles and gamma-ray brightness of AGN

Jet stability, dynamics and energy transport

Jet-induced star formation in gas-rich galaxies

Jet-Powered Molecular Hydrogen Emission from Radio Galaxies

Jet-regulated cooling catastrophe

Jetted Active Galactic Nuclei

Joint 3D modelling of the polarized Galactic synchrotron and thermal dust foreground diffuse emission

Joint analysis of X-ray and Sunyaev Zel'dovich observations of galaxy clusters using an analytic model of the intra-cluster medium

Joint anisotropy and source count constraints on the contribution of blazars to the diffuse gamma-ray background

Joint Lyα emitters - quasars reionization constraints

Joint QSO-CMB constraints on reionization history

Joint X-ray/Sunyaev-Zel'dovich Analysis of the Intra-Cluster Medium

Journey to the M_BH -sigma relation: the fate of low mass black holes in the Universe

Journeying the Redshift Desert