VIRAC researcher participates in seminar “Optical and Radio Variability of Active Galactic Nuclei: From Intraday Fluctuations to Long-Term Cycles”

July 10, 2026

On 7 July, at an international astrophysics seminar, Ventspils University of Applied Sciences Ventspils International Radio Astronomy Centre (VIRAC) researcher and University of Latvia doctoral student Vladislavs Bezrukovs presented the results of his research on the optical and radio variability of active galactic nuclei (AGN). The seminar was devoted to the topic “Optical and Radio Variability of Active Galactic Nuclei: From Intraday Fluctuations to Long-Term Cycles” and provided an overview of observations and analysis carried out over several years.



The studies were carried out in broad international cooperation with the Institute of Radio Astronomy of the National Academy of Sciences of Ukraine in Kharkiv, the Astronomical Observatory of Odesa I. I. Mechnikov National University, the Vihorlat Observatory in Slovakia, and the radio astronomy group at University College Cork.


A window into the early Universe

Active galactic nuclei (AGN) are among the brightest, most energetic and most mysterious objects in the Universe. Supermassive black holes power them, and their mass can reach billions of solar masses. Because many AGN are billions of light-years away, observing them lets astronomers look into the early past of the Universe and study processes that took place when galaxies were still forming.


AGN can be regarded as high-energy laboratories created by nature. Processes take place in their vicinity whose energies and magnetic field intensities far exceed what humanity is able to achieve even in the most advanced particle accelerators on Earth. Therefore, AGN studies offer a unique opportunity to test physical processes under extreme conditions otherwise inaccessible to experimental research.


Unlike most astronomical objects, AGN are not static. Their brightness in the radio, optical and other ranges of the electromagnetic spectrum can change significantly over time intervals ranging from a few hours to several decades. These changes reflect processes near the black hole, in the accretion disk and in relativistic jets, where particles are accelerated to speeds approaching the speed of light. That, in some cases, significant changes can be observed within a single day indicates extremely rapid and energetic processes in the central regions of galaxies.


Observations in Latvia, Ukraine and Slovakia

The studies used radio observations from the VIRAC radio telescopes in Irbene, as well as optical data from the Baldone Observatory in Latvia, the Vihorlat Observatory in Slovakia, and observatories in Ukraine. The authors analysed several well-known objects, including 3C 84 (Perseus A), 3C 371, OJ 287, BL Lac, MRK 421, and MRK 501.

Using modern time-series analysis methods—Fourier transforms, Lomb–Scargle periodograms, and wavelet analysis—the authors detected variability cycles ranging from a few hours to several years, and even decades.


How to distinguish a cosmic signal from the influence of Earth

One of the most important results of the study is a methodology that makes it possible to separate brightness fluctuations produced by the source itself from changes in the signal caused by the environment between the source and the observer.

The studies showed that low-amplitude radio variability in the centimetre-wave range is often not related to the galaxy itself, but arises from radio waves propagating through the interstellar medium, the solar wind, and Earth’s ionosphere. The developed calibration and data processing methods make it possible to significantly reduce the influence of these effects and determine the true activity of AGN more accurately.


From variability to the structure of galactic jets

In addition to radio and optical variability, the doctoral thesis also analysed the internal structure of AGN using high-resolution observations with the Very Long Baseline Array (VLBA) of the US National Radio Astronomy Observatory. The results indicate a complex structure of magnetic fields in AGN jets, including helical magnetic fields, which may play an important role in jet formation, stability and energy transport.


Successful international cooperation

Part of the results used in the doctoral thesis were obtained within the framework of the Latvian Council of Science fundamental and applied research project PERSEUS (“Joint Latvian–Ukrainian Study of the Peculiar Radio Galaxy Perseus A in Radio and Optical Bands”) and the ERDF postdoctoral project RISE of Dr Artem Sukharev. These projects have become a successful example of scientific cooperation between Latvian and Ukrainian radio astronomy researchers, bringing together observatories, telescopes and expertise across several countries.


A new platform for Latvian radio astronomy

At the seminar, it was emphasised that VIRAC has succeeded in creating a fully fledged high-cadence AGN monitoring and data processing system, which allows Latvia to actively participate in international studies on the physics of galactic nuclei and the evolution of the Universe.

The results obtained provide new information about the nature of active galactic nuclei, strengthen Latvia’s position in the European radio astronomy infrastructure and open up opportunities for further research into the most dynamic and mysterious objects in the Universe.


The seminar was organised within the framework of the European Regional Development Fund project No. 1.1.1.5/3/25/I/012 “International Cooperation and Innovation of Ventspils University of Applied Sciences for the Development of Latvia’s Smart Specialisation”.

https://www.mpifr-bonn.mpg.de/pressreleases/2026/a-nearby-black-hole-as-a-window-into-the-early-universe

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Rector of VUAS becomes a member of the Royal Swedish Academy of Sciences

By Rota Žagare • October 12, 2026
Andris Vaivads, Rector of Ventspils University of Applied Sciences, has been elected as a new foreign member of the Royal Swedish Academy of Sciences' Class for Astronomy and Space Science. Andris Vaivads studies what is commonly known as the magnetosphere around the Earth, other planets and the SunClass for astronomy and space science. He performs his research as a professor in Experimental Space Physics at KTH Royal Institute of Technology in Stockholm. Earlier, he spent 20 years as a researcher at the Swedish Institute of Space Physics in Uppsala. He studies the magnetosphere around Earth, other planets, and the Sun. Much of space is filled with plasma, a gas consisting of electrically charged particles that are influenced, among other things, by magnetic fields. When magnetic fields pointing in different directions reconnect – a process known as magnetic reconnection – large amounts of magnetic energy can rapidly be converted into other forms of energy, including kinetic energy. Andris Vaivads’s research focuses on these processes, where large amounts of energy are converted within small regions of space. Plasma processes can, among other things, produce the Northern lights (Auroras), affect satellites, and heat plasma to tens and hundreds of millions of degrees. The research group at KTH, in which Andris Vaivads spends 20 per cent of his working time, develops instruments to measure electric fields on satellites. The group also designs small measurement probes that can be launched from Esrange Space Centre in Kiruna on rockets. More recently, Andris Vaivads has also studied processes in the solar wind, a kind of plasma wind that plays a major role in space weather. This research uses observations from spacecraft launched by ESA (Solar Orbiter) in Europe and NASA (Parker Solar Probe) in the US. Members of the Royal Swedish Academy of Sciences serve on committees and participate in classes that initiate investigations, respond to consultations, and organise conferences and seminars. Based on the information published on the official website of the Royal Swedish Academy of Sciences.

International Scientific Seminar on Massive Star Formation

By Rota Žagare • September 18, 2026
On 24 September, Ventspils University of Applied Sciences will host the international scientific seminar “Massive Star Formation – Latest Research and Developments”, organised by the Ventspils International Radio Astronomy Centre (VIRAC). The seminar will bring together researchers and those interested in research with visiting scientists from the United States. The seminar will feature scientist Dr Todd R. Hunter and Lead Astronomer Dr Crystal L. Brogan from the U.S. National Radio Astronomy Observatory (NRAO). The guests will present current research in radio astronomy, state-of-the-art observational infrastructure, and the opportunities it provides for studying the Universe and the processes of star formation. Dr Todd R. Hunter will give a presentation entitled “Exploring the Universe at Centimeter Wavelengths: The Next Generation Very Large Array”, while Dr Crystal L. Brogan will present “Searching for Our Cosmic Origins Using the Atacama Large Millimeter/submillimeter Array”. The seminar will provide researchers with an opportunity to discuss the latest research findings and methods with internationally recognised experts in radio astronomy, as well as to explore opportunities for future scientific collaboration. Such international knowledge-exchange activities strengthen the research capacity of Ventspils University of Applied Sciences and promote the involvement of Latvian researchers in the international radio astronomy research community. 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). 

VUAS Invites to an Open Lecture on the Birth of Massive Stars

By Rota Žagare • September 18, 2026
On Friday, 25 September, at 16:15, Ventspils University of Applied Sciences invites everyone interested to attend the popular science open lecture “From Cosmic Cloud to Star: How Massive Stars Are Born”. The lecture will offer an engaging and accessible introduction to how massive stars are born, how astronomers are able to observe their formation, and what these studies can reveal about the origins and evolution of our Universe. The lecture will be delivered by guests from the U.S. National Radio Astronomy Observatory (NRAO) – scientist Dr Todd R. Hunter and Lead Astronomer Dr Crystal L. Brogan. Both researchers use modern radio astronomy techniques to study star formation and processes taking place throughout the Universe. The lecture is particularly suitable for astronomy enthusiasts as well as anyone interested in space and the methods scientists use to explore the Universe. No prior knowledge of astronomy is required. The lecture will be held in English, and participation is free of charge. The open lecture will complement the European Researchers’ Night programme in Ventspils. After the lecture, participants will have the opportunity to continue exploring science at the VIZIUM Science Centre, where European Researchers’ Night activities will take place. The lecture is organized with the financial support of the Baltic-American Freedom Foundation (BAFF), in cooperation with the Ventspils International Radio Astronomy Centre (VIRAC).

Ventspils Radio Astronomers Introduce Artificial Intelligence Methods into Their Research

By Rota Žagare • September 11, 2026
As the availability of artificial intelligence (AI) tools continues to grow, so do their capabilities and the range of tasks they can perform, including increasingly complex and sophisticated ones. Consequently, AI is finding applications in ever narrower and more specialised fields. Scientific research in astronomy is no exception, including radio astronomy and related theoretical fields, which are among the areas of research pursued by scientists at the Ventspils International Radio Astronomy Centre (VSRC) of the Institute of Engineering at Ventspils University of Applied Sciences. AI is based on existing knowledge and cannot independently interpret newly generated scientific results. Nevertheless, AI-assisted data processing, generation of program code, partially repetitive data rows and other types of information, as well as the initial compilation and review of large volumes of information on a scientific topic or, for example, the operation of an existing program, can facilitate certain tasks when carried out under careful supervision and verification by a researcher. The results can, in turn, be checked using another version of an AI agent. However, these approaches do not necessarily reduce the overall amount of work or the time required to complete it. To make the most effective use of the opportunities offered by AI and to communicate this knowledge in an accessible way so that it can subsequently be learned and adopted by everyone involved in research, including members of the older generation of scientists, VSRC launched a series of seminars on the use of AI in science in autumn 2026. The series places particular emphasis on astrophysics and radio astronomy, including radio interferometric observations using the Irbene Radio Telescope (IRT) and the LOFAR network. The first seminar was led by VSRC scientific assistant Gints Jasmonts, who shared his knowledge and experience on 3 September. He provided an introduction to the world of AI and presented examples from his own work in computer science and astrophysics. The discussion focused primarily on large language models available through chat interfaces, search engines and programming environments. At their core, these AI systems operate by predicting the next word or token based on the preceding context. The seminar concluded with a discussion, which revealed that participants are already using AI in their everyday work. At the same time, it became clear that learning how to apply the diverse capabilities of AI specifically to research will require further learning. The next seminar will therefore have a more practical focus. 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).

Ventspils Researchers Present Latest Discoveries on Massive Star Birth at International Astrophysics Symposium in Germany

By Rota Žagare • August 31, 2026
Dr. Artis Aberfelds, Senior Researcher at the Engineering Research Institute "Ventspils International Radio Astronomy Centre" (VIRAC) of Ventspils University of Applied Sciences, participated in the prestigious international symposium "SFB 1601: Cologne-Bonn Symposium on the habitats of massive stars across cosmic time" held at the University of Cologne, Germany. A scientific report on methanol maser activity around forming massive stars was presented during the event. Organized by the University of Cologne, the symposium brought together leading astrophysicists and radio astronomers from around the world to discuss the latest discoveries in star formation, the interstellar medium, and the physical processes governing the birth of stars. The research presented by Dr. Aberfelds was developed in close international collaboration with researchers A. Sanna and L. Moscadelli from the Italian National Institute for Astrophysics (INAF). Utilizing the Karl G. Jansky Very Large Array (VLA) in the USA – one of the world's most sensitive radio telescope arrays – the study analyzed the connection between 6.7 GHz methanol (CH3OH) maser emission, stellar radiation, and outflows from young massive stars. Key Findings and Conclusions: Discovery of 5 new maser sources: Observing 22 star-forming regions, 6.7 GHz methanol maser emission was detected in 13 objects, revealing 5 previously unknown maser sources. Precise indicator of stellar location: Over 90% of all detected maser spots are located in close proximity to the central star. Direct link with thermal free-free radio continuum emission: The study revealed a strong correlation between methanol maser luminosity and thermal radio emission, enabling astronomers to more accurately predict and identify weak radiation sources in the Universe in the future. Potential for next-generation radio telescopes: Calculations indicate that more than 30% of the methanol maser population currently remains undetected due to sensitivity limits of existing instruments. These sources will be unlocked by next-generation radio interferometers (such as the ngVLA and SKA). The research and conference participation were carried out within the framework of the Latvian Council of Science (LZP) Fundamental and Applied Research Project „Revealing the physical mechanism of mass ejection around young massive stars via CH3OH masers” (Project No. 1.1.1.9/LZP/1/24/044).

Ventspils University of Applied Sciences Welcomes the New Academic Year with a Modernised Study Environment

By Rota Žagare • August 23, 2026
As the new academic year gets underway, students at Ventspils University of Applied Sciences (VUAS) can already benefit from a range of improvements implemented through the project “Modernisation of the Study Environment at Ventspils University of Applied Sciences”. The upgraded facilities include a newly equipped computer lab with modern computers and monitors, a renovated laboratory with new furniture designed for the needs of the study process, as well as upgraded physics laboratories with new experimental equipment and technology. Further improvements have been introduced in other classrooms, where modern interactive screens have been installed. These provide lecturers and students with greater opportunities to use digital learning materials during classes and make the learning process more interactive. The screens can be easily connected to both lecturers’ and students’ computers, allowing them to display presentations, coursework, projects and other study materials. A particular focus of the project has been the modernisation of the physics laboratories. Students can now work with new experimental laboratory equipment, enabling them to complement theoretical knowledge with practical experiments and hands-on experience with modern technologies. The newly installed laboratory furniture provides a more comfortable and functional workspace, while the layout of the laboratory has also been designed with accessibility in mind, ensuring that the environment is convenient for everyone. The modernised computer lab likewise creates new opportunities for students to complete practical assignments, develop programming skills, work on projects and use the software required for their studies. The modernisation of VUAS study environment, however, is still ongoing. Further improvements are planned as the project continues. The sound systems in two large auditoriums will be renewed, improving the technical facilities for lectures, presentations and other events. The physics laboratories will also be equipped with additional electronic measuring instruments, giving students even more opportunities to carry out practical work, experiments and measurements. The project will therefore continue to bring benefits to students, contributing not only to the modernisation of individual study rooms and equipment, but also to the gradual development of the university’s study environment as a whole. As part of the project, the infrastructure supporting the study programmes implemented by the Faculty of Information Technologies is being improved, with particular emphasis on the modernisation of laboratories, auditoriums, computer equipment and other facilities essential to the study process. T he project “Modernisation of the Study Environment at Ventspils University of Applied Sciences”, No. 4.2.1.8/2/25/I/007, is being implemented from 1 September 2025 to 31 August 2027. The total project budget is EUR 215,083.00, of which 85%, or EUR 182,820.55, is financed by the European Regional Development Fund, while 15%, or EUR 32,262.45, is financed from the state budget.
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