Effects of a Short-Term Increase in the Intensity of 630.0-nm Emissions of Atomic Oxygen [OI] at Lower Thermospheric Altitudes due to Anthropogenic Activity

The paper examines the results of optical observations obtained during Radar Progress experiments to study the effects (the occurrence of extensive, faintly luminous regions and a decrease in plasma concentration) arising from a release of fuel-combustion products from spacecraft engines into the upper atmosphere of the Earth. Analysis of the results of controlled experiments on the injection of “plasma-quenching” compositions into the ionosphere at orbital altitudes indicates that the observed increase in [OI] 630.0-nm intensity in the Radar Progress experiments as a consequence of chemical modification of the ionosphere. The contribution of various components of the injected substance (H 2 , OH, Н 2 О, CO, and СО 2 ) to the increase in the intensity of atomic oxygen [OI] luminescence at a wavelength of 630.0 nm and to a change in the concentration of the charged component of the upper atmosphere is considered. It is shown that the change in the luminescence intensity and the concentration of the charged component are due to different chemical reactions. The largest contribution to the increase in luminescence intensity is made by the injection of hydrogen and carbon dioxide into the atmosphere, while the decrease in the concentration of plasma particles is mainly caused by the injection of water vapor. It has been found that the characteristic spatiotemporal scales of luminous regions occurring in the upper atmosphere allow them to be recorded by modern spectrophotometric equipment from the Earth’s surface without additional information about the time of ignition of the spacecraft engines.