An Earth-sized radio observatory just got better: South Africa’s MeerKAT telescope joins forces with the European VLBI Network of telescopes
South Africa’s MeerKAT radio telescope has successfully conducted very long baseline interferometry (VLBI) observations with telescopes of the European VLBI Network (EVN)—currently the world’s most sensitive VLBI network. Their synergy sets a new standard for global collaboration and significantly enhances both resolution and sensitivity, opening new avenues for scientific exploration.
All sky, all the time – A new radio sky monitor for transients and technosignatures
Breakthrough Listen, headquartered at the University of Oxford – the most ambitious project to date searching for technosignatures (signs of technology as an indicator of extraterrestrial intelligence) – is partnering with ASTRON, the Netherlands Institute for Radio Astronomy, and the University of Manchester, to deploy a new all-sky monitor at the Westerbork Observatory in the Netherlands. The new experiment takes phased array feeds (PAFs) – essentially wide-field radio cameras – that were previously deployed on the Westerbork Synthesis Radio Telescope (WSRT), and installs them on the ground, looking up at the sky directly.
Sweden and the United Kingdom Join the LOFAR ERIC
Sweden and the United Kingdom have joined the LOFAR ERIC (European Research Infrastructure Consortium) as a member, following the decision of the Council on 26 March 2025. This significant expansion brings the total membership to eight countries, marking an important milestone in the growth of this pioneering research infrastructure.
ASTRON receives €4.6 million to widen and sharpen LOFAR’s cosmic vision
The Dutch Research Council (NWO) has awarded over €4.6 million to ASTRON, the Netherlands Institute for Radio Astronomy, for a major upgrade to the Low-Frequency Array (LOFAR) radio telescope. The project, called LOFAR Enhanced Network for Sharp Surveys (LENSS), will significantly increase LOFAR’s observational capabilities, enabling astronomers to view four times more of the sky simultaneously while producing images with unprecedented clarity.
LOFAR Multicast roll-out
© CEP Project team
Multicast is a network technology that allows the same data to be sent once to groups of devices, replicating inside the network. A sender only needs to transmit the data once, and interested parties can subscribe to the Multicast group. The same technology is used for TV broadcasts and within Internet Service Provider networks for IPTV.
Multicast allows us to duplicate antenna data streams in the network. This has three important implications. First, it makes LOFAR more flexible, as it enables streaming data to multiple users and science cases. In addition, we can run A/B and development tests with two software versions on the same data, which directly benefits the Cobalt3 software development. And finally, it allows us to remove the first transpose action in the Cobalt software, and transition to a new Cobalt architecture without Infiniband.
Network changes impact all LOFAR sub-systems. This makes changing it a potentially tedious task. For LOFAR2.0 the Multicast roll-out was planned for 20 May, during a busy day dedicated to this effort. A core team of experts spent the full day to update the system and fixing resulting problems. All three LOFAR2.0 Production Test System stations were transferred to the LOFAR2.0 network, which includes better security through segmentation and filtering. This reduces the risk of failures, as problematic devices can now only cause trouble within a station and will not affect the entire network.
The Uniboard configuration was updated to use unique MAC addresses, and to transmit to a Multicast group. The first change removed tens of thousands MAC moves per second in the LOFAR switches, which were not within Ethernet specifications. The second change ensures that the Uniboards never send data to unknown addresses, which can flood the entire network. These two changes make the LOFAR network fully Ethernet compliant and more robust.
The next step was to enable Multicast in the network itself. The transfer to Multicast encountered many small and some large hurdles and required some additional bug fixing and updating on the next day. The system was operational again by Thursday 22 May. This change has achieved many milestones needed for the LOFAR2.0 network, and allows the new LOFAR2.0 stations to connect directly to the new network.
The image shows how data streams from the router receiving the station data into the Cobalt correlator nodes (green and blue lines in the image). Center top is the router, which talks to the top-rack switch ACX-B3-0. From the switch the Cobalt2 nodes are receiving multiple data streams with different data rates. Node CBT206 is subscribed to 6 and 9 Gbps, at the same time Cobalt node CBT201 subscribes to 3 and 6 Gbps. Receiving these two simultaneous streams is the trademark of a Multicast system.
CASPER Workshop 2025
Mon 08 Sep 2025 - Fri 12 Sep 2025
The CASPER workshop is a semi-annual workshop where FPGA, GPU, and general heterogeneous system programmers get together to discuss new instruments in radio astronomy, as well as the tools and libraries for developing and manipulating these instruments.