Modern radio astronomy relies not only on advanced technologies and international research infrastructure, but also on knowledge exchange and training the next generation of researchers. One of the most prominent examples of this collaboration is LOFAR (LOw Frequency ARray). This Europe-wide radio astronomy network enables scientists to explore the Universe at low radio frequencies and opens up new opportunities in various fields of astronomy. To introduce early-career researchers from different countries to this unique infrastructure, its latest technological developments, and the research opportunities it offers, ASTRON, the Netherlands Institute for Radio Astronomy, regularly organises LOFAR schools. Jesus Alberto Cazares Montes, a visiting leading researcher at the Ventspils International Radio Astronomy Centre (VIRAC), Engineering Research Institute “Ventspils International Radio Astronomy Centre” (ERI VIRAC), Ventspils University of Applied Sciences, also took part in one of these training programmes.

The Netherlands Institute for Radio Astronomy (ASTRON), founded in 1949, plays an important role in developing radio astronomy infrastructure and research. One of its major initiatives is LOFAR (LOw Frequency ARray), a European network of radio telescope stations designed to explore the Universe at low radio frequencies. The network is currently upgrading to LOFAR 2.0, which will improve its observational capabilities and the quality of astronomical images.

To support the next generation of radio astronomers, ASTRON organises a LOFAR school every two years. The latest edition, held this autumn, brought together participants to learn about the technical and scientific aspects of radio astronomy using LOFAR. The programme covered collecting and processing observational data, reconstructing images, and the technical challenges of operating the array. Researchers also presented LOFAR applications across diverse fields, including pulsars and transient energetic phenomena, solar physics, cosmic rays, lightning, stars, and exoplanets.

The school also offered participants practical research experience. During the final three days, they worked in teams on challenges proposed by ASTRON researchers, addressing questions related to the researchers’ ongoing scientific work. On the final day, each team presented its results, giving participants an opportunity to apply their knowledge to research problems resembling those encountered in professional radio astronomy.

An important topic throughout the school was the ongoing transition from LOFAR 1.0 to LOFAR 2.0. The upgrade involves improvements to the software and data-processing systems, as well as advances in the calibration and operation of the array. LOFAR 2.0's improved data-processing capabilities can produce significantly more detailed, higher-quality astronomical images.

The LOFAR network comprises stations distributed across several European countries. Latvia hosts one of these stations, the northernmost and second-easternmost in Europe (after Bulgaria). Other countries are upgrading or expanding their participation in the network, including Sweden, which has already upgraded its station, and Czechia, which plans to establish a station.

During the LOFAR school, participants also observed a symbolic tradition marking the network’s transition to LOFAR 2.0. Whenever a station completes its upgrade, ASTRON places a soft toy bearing the station’s name in a transparent tube representing the upgraded stations. A European Union flag is also added to a map of Europe when a station begins the upgrade process. During the school, the participants witnessed two additions to the tube, representing a Polish station and the newly completed Bulgarian station.

Latvia’s station has not yet been upgraded to LOFAR 2.0. Its modernisation would expand the country’s ability to contribute to international radio astronomy, allowing researchers to take advantage of the network’s improved capabilities. The station has the potential to support research at Latvian academic institutions and strengthen scientific collaboration across the Baltic region.

The transition to LOFAR 2.0 would therefore represent more than a technical improvement. It would be an important step in maintaining and developing Latvia’s role in European radio astronomy, ensuring Latvian researchers can fully participate in the scientific opportunities offered by this evolving international infrastructure. Achieving this goal will require continued institutional support and investment in research infrastructure.

This information has been prepared within the framework of the project “Ventspils University of Applied Sciences` International Cooperation and Innovation for the Development of Latvia’s Smart Specialisation” (Project No. 1.1.1.5/3/25/I/012).