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Electric charging of spacecraft is responsible for more than a half of registered anomalies in their operation. Static electricity may cause significant complications for lunar missions. Martian dust devils may produce radio noise and electric fields in excess of 1000 V/m.

Chemical sputtering of different types of carbon and graphite materials in oxygen plasma flows with particle energies lower than 100 eV is investigated. The dependence of the chemical sputtering coefficient for undoped materials on the structure is weakly expressed. The sputtering coefficient of boron-doped materials decreases with their degree of doping. The surface relief of some carbon materials is studied with the help of a scanning electron microscope.

The empirical basis of this work is data on school students of Khanty-Mansi Autonomous District - Yugra. The author arrive at certain conclusions concerning the influence of the socioeconomic situation of students families on education results.

The surface topography of samples of graphite USB-15, pyrolytic carbon PGI, pyrolitic graphite UPV-1, and polyimide PM-1E exposed to accelerated oxygen-plasma beams has been studied by scanning electron microscopy. Surface etching by fast oxygen particles results in the formation of a system of cone/column-like protrusions. As the material mass loss increases, the protrusions increase in size, and the surface topography transforms. Etching of carbon-based materials leads to enrichment of the surface layer with carbon, which is most pronounced in the boron-doped graphite.

Valerian Grigor'evich Shevchenko (Obituary) Yu V Galaktionov, Mikhail V Danilov, Vladimir S Imshennik et al. Anatoli Aleksandrovich Vlasov (obituary) I P Bazarov, N N Bogolyubov, Boris B Kadomtsev et al. Physics and astronomy at Moscow University (On theUniversity's 225th anniversary) B I Spasski, L V Levshin and V A Krasil'nikov Configurational splitting of the giant dipole resonance in atomic nuclei B S Ishkhanov, I M Kapitonov, Vladimir G Neudachin et al. German Stepanovich Zhdanov (Obituary) N B Brandt, B K Vanshten, A S Ilyushin et al. Yuri Mikhalovich Shirokov (Obituary) N N Bogolyubov, S N Vernov, Vasilii S Vladimirov et al. Dmitri Vladimirovich Skobel'tsyn (Obituary) A M Baldin, N G Basov, Vitalii L Ginzburg et al. Igor' Borisovich Teplov (Obituary)

The spatial distribution and the charge-accumulation kinetics during electron irradiation have been studied. The value of the injected charge which produces the destruction of the glass has been evaluated. Experiments have been made on the transmission of polarized light through a charged specimen. An optical method is proposed for measuring the distribution of the aecumulated-charge density throughout the specimen.

The behaviour of electron-irradiated inorganic glasses has been investigated. The coefficient of electron capture in the creation of a space charge is estimated. Experimental data on the spontaneous and initiated breakdowns of charged glasses are presented.

A single pulse from a neodymium laser is used to initial electrical breakdown in glasses which accumulate and preserve a space charge induced by a beam of rapid monoenergetic electrons. Laser initiation permits use of high-speed recording apparatus and study of the initial stage of electrical breakdown in the charged glasses. A time delay in electrical breakdown relative to the initiating optical radiation was observed and measured, corresponding to the time of formation of a conductive channel between the region of space-charge localization and the specimen surface. Growth rates of the conductive channel are determined for surface and volume initiation, and possible mechanisms of laser initiation are considered.

The luminescent charac te r i s t i cs of optical g lasses were measured at electron and proton flux densities of 10~-10 t~ see i .cm -2 and for energies of several hundred keV of the part icles interacting with the glass. The thickness of the investigated glass specimens was grea te r than the mean f ree path of the particles, and there fore the part icles were completely absorbed in the specimens.

The features of formation of electric discharge in electron-irradiated glasses have been investigated. Laser emission was used to excite the discharge. The depth of the initiated discharge has been measured as a function of the sample thickness. Using rapid photographic recording, we have estimated the velocity of discharge propagation in glasses. An abnormal Lichtenberg figure formed as a result of the discharge initiated in the absorption of laser emission in the sample volume has been observed.