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To date, PMN J2134-0419 (at a redshift z = 4.33) is the second most distant quasar known with a milliarcsecond-scale morphology permitting direct estimates of the jet proper motion. Based on two-epoch observations, we constrained its radio jet proper motion using the very long baseline interferometry (VLBI) technique. The observations were conducted with the European VLBI Network (EVN) at 5 GHz on 1999 November 26 and 2015 October 6. We imaged the central 10-pc scale radio jet emission and modelled its brightness distribution. By identifying a jet component at both epochs separated by 15.86 yr, a proper motion of μ = 0.035 ± 0.023 mas yr-1 is found. It corresponds to an apparent superluminal speed of βa = 4.1 ± 2.7 c. Relativistic beaming at both epochs suggests that the jet viewing angle with respect to the line of sight is smaller than 20°, with a minimum bulk Lorentz factor Γ = 4.3. The small value of the proper motion is in good agreement with the expectations from the cosmological interpretation of the redshift and the current cosmological model. Additionally we analysed archival Very Large Array observations of J2143-0419 and found indication of a bent jet extending to ∼30 kpc. [ABSTRACT FROM AUTHOR]

The Square Kilometre Array (SKA) will be an ultrasensitive radio telescope, built to further the understanding of the most important phenomena in the Universe, including some pertaining to the birth and eventual death of the Universe itself. Over the next few years, the SKA will make the transition from an early formative to a well-defined design. This paper outlines how the scientific challenges are translated into technical challenges, how the application of recent technology offers the potential of affordably meeting these challenges, and how the choices of technology will ultimately be made. The SKA will be an array of coherently connected antennas spread over an area about 3000 km in extent, with an aggregate antenna collecting area of up to 106 m² at centimeter and meter wavelengths. A key scientific requirement is the ability to carry out sensitive observations of the sky over large areas (surveys). The "survey speed" of the SKA will be enabled by the application of the most up-to-date signal-processing technology available. The SKA science impact will be widely felt in astroparticle physics and cosmology, fundamental physics, galactic and extragalactic astronomy, solar system science, and astrobiology. [ABSTRACT FROM AUTHOR]

This triennium began with an action to re-create the Terms of Reference for the Working Group Global VLBI (WG-GV). These had been lost over the years since the Group was established in 1990. Fortunately, the personal archive of one long-term member yielded a copy of the original memorandum by R. D. Ekers, which was found to coincide quite well with current practice and areas of interest. New Terms of Reference, based on modern conditions, were drafted and accepted by both IAU and URSI. [ABSTRACT FROM PUBLISHER]

The Square Kilometre Array (SKA) is a global project to design and build a new generation radio telescope at metre to centimetre wavelengths. [ABSTRACT FROM PUBLISHER]

LOFAR (Low Frequency Array) is an innovative radio telescope optimized for the frequency range 30–240 MHz. The telescope is realized as a phased aperture array without any moving parts. Digital beam forming allows the telescope to point to any part of the sky within a second. Transient buffering makes retrospective imaging of explosive short-term events possible. The scientific focus of LOFAR will initially be on four key science projects (KSPs): (i) Detection of the formation of the very first stars and galaxies in the universe during the so-called epoch of reionization by measuring the power spectrum of the neutral hydrogen 21-cm line (Shaver et al. 1999) on the ∼ 5′ scale; (ii) Low-frequency surveys of the sky with of order 108 expected new sources; (iii) All-sky monitoring and detection of transient radio sources such as γ-ray bursts, X-ray binaries, and exo-planets (Farrell et al. 2004); and (iv) Radio detection of ultra-high energy cosmic rays and neutrinos (Falcke & Gorham 2003) allowing for the first time access to particles beyond 1021 eV (Scholten et al. 2006). Apart from the KSPs open access for smaller projects is also planned. Here we give a brief description of the telescope. [ABSTRACT FROM PUBLISHER]

The questions addressed in this large and popular meeting were: What mature proposals for the new large astronomical facilities of the next decade are available? When can they be funded? What international planning is underway? [ABSTRACT FROM PUBLISHER]