Observation of the Solar Eclipse on June 10, 2021 on the Water Vapor Radiometer of the Institute of Applied Astronomy, Russian Academy of Sciences

Abstract

The results of observations of the solar eclipse on June 10, 2021, which were carried out at the Svetloeobservatory (60.53° N, 29.78° E, Leningrad Province) for the first time using the water vapor radiometerand radio telescopes RT-13 and RT-32 together are presented. The eclipse curves obtained at the radiometeroperating frequencies of 20.7 and 31.4 GHz were compared with the change in the area of the open part of theSun and show good agreement (match to an accuracy of 2% during the cloudless period). Assuming a uniformdistribution of radio brightness across the solar disk, the brightness temperature was estimated to be 9060 ± 380and 8050 ± 300 K at these frequencies, respectively. It was concluded that even in the epoch of a deep minimumof solar activity, the brightness of the solar disk in the microwave range remains unchanged (independentof the cycle number)