On the programs of monitoring studies of space weather based on radio astronomical and magnetometric observations

Since its commissioning in 1987, the URAN-4 radio telescope of the RI NASU has been conducting a program for monitoring the fluxes of powerful radio sources in order to identify the properties and effects of space weather. Among the observed radio sources are the remnants of supernova explosions CAS A and TAU A, radio galaxies CYG A and VIR A. Since 2017, joint research programs have been launched with the Ventspils International Radio Astronomy Centre in Latvia to study the variability of extragalactic radio source fluxes and the effects of space weather manifestations. Observations were carried out using the RT-32, RT-16 and LOFAR radio telescopes, in 2019-2022, 2025 to the present, at frequencies of 5, 6.1, 6.7, 8-8.7 GHz (RT-32 and RT-16), also LOFAR in frequency band 30-60 MHz. Since 2017, radio astronomical observations of space weather manifestations in the zone of the Odessa Magnetic Anomaly have been supplemented by magnetometric observations of the Institute of Geophysics NASU at observatories in Kyiv, Odesa and Lviv. Observations of the 2025 solar eclipses were carried out with the participation of the LOFAR (Latvia), URAN-4 (Ukraine) observational data from the KAIRA radio telescope, magnetometers and riometers of the SODANKYLA observatory in Finland, as well as a network of magnetometric stations of the Institute of Geophysics NASU. The implemented comprehensive program has provided the foundation for the project funded by the Latvian Council of Science, “Characterisation of Extreme Space Weather Effects on the Ionosphere”, aimed at studying local manifestations of space weather effects along the historical “Struve Geodetic Arc,” with the participation of Latvia, Finland, and Ukraine. Keywords: geomagnetic pulsations (Pi), ionosphere, radio scintillation, magnetosphere, solar eclipses, geomagnetic storms