Abstract
The results of observations of the solar eclipse on June 10, 2021, which were carried out at the Svetloe observatory (60.53° N, 29.78° E, Leningrad Province) for the first time using the water vapor radiometer and radio telescopes RT-13 and RT-32 together are presented. The eclipse curves obtained at the radiometer operating frequencies of 20.7 and 31.4 GHz were compared with the change in the area of the open part of the Sun and show good agreement (match to an accuracy of 2% during the cloudless period). Assuming a uniform distribution of radio brightness across the solar disk, the brightness temperature was estimated to be 9060 ± 380 and 8050 ± 300 K at these frequencies, respectively. It was concluded that even in the epoch of a deep minimum of solar activity, the brightness of the solar disk in the microwave range remains unchanged (independent of the cycle number).
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The work was carried out within the framework of the state assignment of the SAO RAS, approved by the Ministry of Science and Higher Education of the Russian Federation.
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Il’in, G.N., Bykov, V.Y., Peterova, N.G. et al. Observation of the Solar Eclipse on June 10, 2021 on the Water Vapor Radiometer of the Institute of Applied Astronomy, Russian Academy of Sciences. Geomagn. Aeron. 62 (Suppl 1), S96–S102 (2022). https://doi.org/10.1134/S0016793222600643
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DOI: https://doi.org/10.1134/S0016793222600643