Yu. A. Plastinin

Auroral activity caused by high-power radioemission from the SURA facility

A series of experimental modifications of the ionosphere in the HF range, performed at the SURA facility base, together with optical measurements onboard the International Space Station (ISS), indicated that such impacts on the ionosphere are effective when the facility operational frequency is higher than the critical plasma frequency (for the main ionospheric F2 layer). The experimental measurements were supported by measurements at ground-based observatories, ISS, and the Demeter and GPS satellites. The analysis results of the entire data set are presented. The ray HF radio tracing for the experiment of October 2, 2007, has been calculated, and it has been indicated that the ionosphere to the north of the facility up to 60°–62° N latitudes was irradiated by the facility beam (the effects of ray redistribution and refocusing) due to refraction on the gradient of the F2 layer critical frequencies. An analysis of the ground-based and satellite measurements (both in the vicinity of a heater and in the magnetically conjugate region) indicates that it is possible to trigger a substorm in experiments with the Sura heating facility.

Illumination of the Earth’s ionosphere by the vacuum ultraviolet radiation reflected by the moon

The spectral curve of the flux density of the radiation, which is reflected by the full moon towards the Earth’s ionosphere within a wavelength range of 200–1700 Å, has been presented. This curve is obtained by the approximation of space experiment data available in the scientific literature on the lunar spectral albedo and solar spectrum. Estimates of maximum values of spectral densities of fluxes reflected by the full moon in the neighborhood of wavelengths of ionization of basic ionospheric particles (neutral atoms of H I, He I, N I, O I, and Ar I and ions of He II, N II, O II, Ar II, N III, O III, and Ar III, as well as molecules of H2, N2, and O2) are given.

The influence of kinetics of neutral particles on near-surface glow of spacecraft

A technique for calculation of the glow around low-orbit spacecraft is developed, taking into consideration the kinetics of neutral particles. Using this technique, the altitude ranges are determined where molecular processes dominate over ion-electron mechanisms. The influence of the molecular composition of the Earth’s atmosphere on the production of excited radicals NO2* near the surface of spacecraft is studied in some detail.