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Employees of the Department of Atmospheric Physics and Microwave Diagnostics of the A.V. Gaponov-Grekhov Institute of Applied Physics of the Russian Academy of Sciences discovered previously unknown features of their own atmospheric ozone radiation. As you know, the ozone layer, located mainly at stratospheric altitudes (10-50 km), protects all living organisms on our planet that are not constantly hidden by a layer of water, the earth's surface or otherwise from the harmful effects of ultraviolet radiation from the Sun. Therefore, its monitoring is critically important for the biosphere, especially in the context of global depletion of the layer observed since the late 1970s, as well as spring ozone holes in the polar regions. Radiation/absorption of atmospheric gases in various electromagnetic wave ranges (from ultraviolet to terahertz) is widely used for environmental monitoring and pollution control through various instruments from the Earth's surface, aircraft, stratostats and satellites. In order to restore the vertical profile of ozone from ground measurements in the microwave range, two strongest lines are usually used, lying in the corresponding windows of atmospheric transparency near the frequencies of 110.8 and 142.2 GHz. Studies using the upgraded Nizhny Novgorod ozonometer operating near 110.8 GHz allowed geophysicists of the IPF RAS to perform long-term field measurements of the radiation of this ozone line with the best spectral resolution to date (~12 kHz). Previously, Swiss scientists began to carry out such precision measurements to develop a technology for measuring zonal wind velocity by the Doppler shift of the center of the ozone line near 142.2 GHz. However, it is known that this line is sensitive to the amount of surface humidity, so such measurements can not be carried out everywhere and not in all seasons. In turn, the 110.8 GHz line is located in the atmospheric transparency window with noticeably lower absorption and is potentially more suitable for organizing network measurements of zonal wind. Measurements in Nizhny Novgorod were carried out in a northerly direction in order to exclude the influence of zonal wind at the first stage. Processing of long ranges of atmospheric brightness temperature spectra made it possible, for the first time in field experiments, to determine the central frequency of the 110.8 GHz line with record high accuracy (~16 kHz). The found value turned out to be 130 kHz less than the laboratory measured value and differs markedly from the calculations of modern models used to restore the vertical distribution of ozone concentration according to spectral measurements. The obtained result can be used as a reference point both for the creation of new microwave equipment for monitoring the atmosphere, and for testing modern semi-empirical and quantum chemical methods and models. The work was supported by the Russian Science Foundation 22-12-00064. Kulikov M.Yu., Krasil’nikov A.A., Belikovich M.V., Ryskin V. G., Shvetsov A.A., Skalyga N.K., Kukikn L.M., and Feigin A.M., High precision measurements of resonance frequency of ozone rotational transition J = 61,5–60,6 in the real atmosphere // Remote Sensing, 15, 2259, 2023. https://doi.org/10.3390/rs15092259. Illustration: A mobile microwave ozonometer of the IPF RAS with a digital spectrum analyzer designed to measure the ozone concentration profile in the altitude range of 15-75 km. Red line: the measured spectrum of the central part of the line of atmospheric ozone intrinsic radiation. Blue line: model spectrum with parameters corresponding to laboratory measurements The source of the illustration: IPF RAS Information provided by the press service of the IPF RAS Information taken from the portal "Scientific Russia" (https://scientificrussia.ru /)