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The development of new devices for research in physics of the upper atmosphere and near-Earth space, which can be used to carry out controlled experiments on the modification of the ionosphere by powerful short-wave radiation, is an urgent task of modern solar-terrestrial physics, space weather, operation of satellite constellations in near-Earth space, radio communications, and radar. The paper describes a modern heating facility, created within the framework of the National Heliogeophysical Complex of the Russian Academy of Sciences. We review the tasks facing the heater, discuss its main technical characteristics, and describe the capability of the observational infrastructure surrounding the heating facility. The paper justifies the long-term benefits of the development of a heating facility at middle latitudes of Eastern Siberia, which can radiate in a frequency range 2.5–6.0 MHz with an effective power of the order of several hundred megawatts. It is important that the heater will be surrounded by such multifunctional instruments as the modern incoherent scatter radar, mesostratospheric lidar, observational systems that can provide a wide range of possibilities for diagnosing artificial plasma disturbances and artificial airglow structures.

Studies of the upper atmosphere have to be performed using optical photometric and spectrometric means. Modern devices allow precise photometry of the glow of the night atmosphere — airglow — with high temporal spatial and spectral resolution. As a result, the obtained airglow parameters make it possible to determine the physicochemical properties of the upper atmosphere and observe their variation under the influence of various factors. The National Heliogeophysical Complex, which is being created in Eastern Siberia, is therefore to include a certain set of modern optical instruments. The paper presents the main phenomena that will be investigated by the optical instruments of the complex, provides information on their composition and scientific goals, presents the results of preliminary studies performed using a prototype of the instruments. As a result of the studies, the presence of a significant (about 10 m/sec) vertical wind at various altitudes (100 and 250 km) was established, the importance of taking into account the vertical wind to study the vertical dynamics of the charged component was demonstrated. The long-term dynamics of the vertical wind at an altitude of about 100 km has a pronounced seasonal variations and the absence of diurnal variations, whereas the dynamics of the vertical wind at an altitude of 250 km has a pronounced diurnal variations, which is mostly clearly defined in winter. This suggests the presumed presence of vertical circulation cells at various altitude levels. The possibilities of optical stereoscopy and differential image analysis methods are demonstrated, as applied to the study of fast luminous formations and conducting active ground and space experiments to modify Earth's ionosphere. We report the results of the determination of a three-dimensional picture of a long-lived meteor track with the use of two wide-angle cameras. We propose an algorithm that allows us to get a stereo image of events occurring in the upper atmosphere, recorded simultaneously from different observation points. The joint work of the tools of this complex and the development of cooperation with third-party organizations are shown to be a good enough direction for further study of the vertical dynamics of Earth’s upper atmosphere and space weather phenomena.

The paper presents data on long-lived (~20–40 min) meteor trails. We describe a group of soliton-type meteor trails expanding at transonic speeds. Radio sounding data evidences that the latter include ~7–8 min ionization trails. We also consider one event with an ordinary shape and dynamics of meteor trails. These ordinary meteor trails are formed due to wind flows at heights of meteor glow. We describe the space-time structure of the detected meteor trails. In particular, in the November 18, 2017 event the typical size of the expanding trail area reached approximately 400 km and retained its semioval shape. The meteor trail propagated mainly in the horizontal plane at heights of ~86–91 km. We examine possible mechanisms of long-lived meteor trails propagating at transonic speeds. We estimate speed variations of meteor particles of size from 1μm to 10 mm for ~70–120 km heights during their horizontal motion. It is shown that the mode of meteor particle motion without deceleration on the typical timescale of ~10 3 s at 70–90 km heights can be realized only for large particles over 100 μm. Mechanisms and spectral composition of long-lived meteor trail glow are discussed.

We study the spatiotemporal dynamics of mid-latitude aurora from observations in the south of Eastern Siberia during St. Patrick’s severe geomagnetic storm on March 17, 2015. We perform a morphological analysis of characteristics of the observed auroras. A preliminary conclusion is drawn that the analyzed event is the result of the manifestation of mid-latitude auroras of two types (type “d” and SAR arc) and ordinary aurora observed at the northern horizon. The maximum intensity of the dominant emission [OI] at 630.0 nm (~14 kR) allows this mid-latitude aurora to be attributed to the extreme auroras occurring in mid-latitudes, which is second only to the November 20, 2003 superstorm (~19 kR).

We describe the Fabry—Perot interfero-meter designed to study Earth’s upper atmosphere. We propose a modification of the existing data processing method for determining the Doppler shift and Doppler widening and also for separating the observed line intensity and the background intensity. The temperature and wind velocity derived from these parameters are compared with physical characteristics obtained from modeling (NRLMSISE-00, HWM14). We demonstrate that the temperature is determined from the oxygen 630 nm line irrespective of the hydroxyl signal existing in interference patterns. We show that the interferometer can obtain temperature from the oxygen 557.7 nm line in case of additional calibration of the device. The observed wind velocity mainly agrees with model data. Night variations in the red and green oxygen lines quite well coincide with those in intensities obtained by devices installed nearby the interferometer.

This paper presents results of optical observations made during Radar-Progress Experiment performed on April 17, 2013 and July 30, 2014 after approach-correction engines (ACE) of Progress M-17M and Progress M-23M cargo spacecraft in the thermosphere had been started. A region of enhanced emission intensity was recorded during engine operation. This may have been related to the scatter of twilight solar emission along the cargo spacecraft exhaust and to the emergence of additional atomic oxygen [OI] emission at 630 nm. The maximum dimension of the observed emission region was ~330–350 km and ~250–270 km along and across the orbit respectively. For the first time after ACE had been started, an expansion rate of emission region was ~ 7 and ~ 3.5 km/s along and across the orbit respectively. The maximum intensity of the disturbance area for Progress M-17M is estimated as ~40–60 R at 2 nm. Progress M-23M Space Experiment recorded a minor disturbance of atmospheric [OI] 630.0 nm emissions, both in near and in far cargo spacecraft flight paths, which might have been associated with the ACE exhaust gas injection.