Geospace Perturbations that Accompanied Rocket Launches from the Baikonur Cosmodrome

The launch of a rocket requires an energy comparable to the energy of many natural processes. For large rockets, the energy release reaches 10–100 TJ, and the power of engines reaches 0.1–1 TW. The energy release per unit volume is much higher than the specific energy content and energy release of all natural processes. During the launch and flight of a large rocket, disturbances in the substratum, the atmosphere, the ionosphere, and even in the magnetosphere occur. Effects from rocket engine burns have been studied for more than 60 years. Research results have been published in hundreds of articles, handbooks, and monographs. It turns out that the effects produced exhibit diverse geophysical phenomena. The effects near the rocket trajectory, namely, the regions of depressed electron density (ionospheric holes), and the generation of infrasound and atmospheric gravity waves (density waves) are investigated better than other effects. Great attention has been paid to studying the geomagnetic effect. The following methods have been used in studies: the Doppler effect, the Faraday, incoherent scattering, ionosonde, magnetometric methods, etc. The effects accompanying the launches and flights of rockets are being actively studied even now. For many years, large-scale (1 to 10 Mm) disturbances that occur after rocket launches have been studied. Their study makes it possible to better understand the mechanisms of the propagation of disturbances from a rocket over global distances, the interaction of subsystems in the Earth–atmosphere–ionosphere–magnetosphere system, and the ecological consequences of rocket engine burns. Disturbances occurring in the atmosphere and geospace substantially depend on the state of the atmospheric–space weather, time of day, season, and phase of the solar cycle. Even with the launch of two identical rockets, disturbances in the mentioned system can be very different. It should be borne in mind that rockets differ in power, trajectories, fuel composition, and the location of cosmodromes. Therefore, studying the response of subsystems to rocket launches and flights remains an urgent problem. The purpose of this study is to describe the results of an analysis of the ionospheric effects of the Soyuz and Proton rockets launched during the 24th cycle of solar activity from the Baikonur Cosmodrome. To observe the effects in the ionosphere caused by the launch of the Soyuz and Proton rockets from the Baikonur Cosmodrome, a vertical sounding Doppler radar was used. As a rule, measurements are carried out at two fixed frequencies of 3.2 and 4.2 MHz. The smaller of them is effective when studying the dynamic processes in the E and F1 layers, and the larger one is effective when studying the F1 and F2 layers. The parameters of ionospheric disturbances that followed the launches of 81 Soyuz rockets and 53 Proton rockets from the Baikonur Cosmodrome in 2009–2021 are analyzed. It is confirmed that there are several groups of delay times for the possible reaction of the ionosphere to the launch and flight of the rockets. These delay times varied widely (from 10 to 300 min). The delay time groups correspond to several groups of apparent horizontal velocities of disturbance propagation (100–200, 390 ± 23 m/s, 0.97 ± 0.10, 1.28 ± 0.13, 1.68 ± 0.13, 2.07 ± 0.13 km/s, and approximately 8 km/s). Slow atmospheric gravity waves, atmospheric gravity waves of man-made origin, density shock waves, slow, and ordinary MHD waves have such velocities. As a rule, the generated perturbations (except for shock waves) are quasi-periodic in behavior with a period in the range from 5 to 20 min. The amplitude of the Doppler shift is 0.1–0.3 Hz. The relative amplitude of quasi-periodic variations in the electron density is typically 1‒10% and rarely reaches 20%.