In 2022, the telescope of the Main (Pulkovo) Astronomical Observatory of RAS obtained astrometric and photometric series of observations of a potentially dangerous asteroid (138971) 2001 CB21 during its approach to Earth. Based on the data obtained and data from the MPC website, the asteroid’s orbit was improved and the circumstances of the encounters were investigated with the Earth and Venus and an assessment was made of the influence of nongravitational effects on its motion. Based on photometric observations of the asteroid, a light curve was constructed and its axial rotation period was confirmed: R = 3.305 ± 0.002 h.

The astrometric observations of potentially hazardous asteroid 2001 QQ142 (139622) were made during its apparition after its close approach to the Earth. The observations were made using the mirror astrograph ZA-320M and D.D. Maksutov meniscus telescope MTM-500M of Pulkovo Observatory. The RMS of obtained series of the asteroid positions are σ = ±0''.21 for ZA-320M and σ = ±0''.07 for MTM-500M observations.

In 2020, two telescopes of the State Astrophysical Observatory of the Russian Academy of Sciences, ZA-320M and MTM-500M, obtained series of observations of the potentially dangerous asteroid 65690 (1991 DG) during its approach to the Earth and carried out their astrometric and photometric processing. Using the coordinates of the asteroid and observations from the MRS site, the orbit of the asteroid was clarified, and the circumstances of the approaches to the Earth and Mars were determined, and an assessment was made of the influence of nongravitational effects on its orbit. Based on the results of photometric processing of the asteroid, a light curve was constructed and the period of its axial rotation was determined: P = 4.3193 ± 0.0028 h.

Asteroids 2010 TK7 and 2020 XL5 are of particular interest because of their behavior, which is similar to the so-called trojan asteroids. In this paper, computer simulations of the orbital evolution of the asteroids in question were carried out using the EPOS software system. The results of the computer simulations suggest that the Earth trojans were not ordinary trojans in the recent past and will most likely shift to another type of orbit in the distant future.

Представлены результаты выявления астероидов, потенциально опасных для внутренних планет. Исследовано орбитальное движение астероида 2022 АЕ1, троянцев Земли (2010 TK7, 2020 XL5) и «рукотворного» астероида 2020 SO. The results of the detection of potentially hazardous asteroids for the inner planets are presented. The orbital motion of asteroid 2022 AE1, the Earth Trojans (2010 TK7, 2020 XL5), and the “man-made” asteroid 2020 SO has been studied.

The astrometric and photometric series of observations of potentially hazardous asteroid (276033) 2002 AJ129 were obtained with MTM-500M telescope of Pulkovo Observatory in the period of its close approach to the Earth on February 4, 2018. The orbital evolution was studied and the influence of non-gravitational effects (solar ra-diation pressure and the Yarkovsky effect) was estimated. The axial rotation period (P = 3.9222 +/- 0.0008 h) of the asteroid and the color indices (B-V = 0.687 +/- 0.050, V-R = 0.405 +/- 0.027, R-I = 0.178 +/- 0.044) were determined from the photometric series of observations.

Results of studies of dielectric response and polarization in PbCo1/3Ta2/3O3 (PCT) single crystals grown by spontaneous crystallization are presented. Anomalies in the temperature dependence of the complex dielectric permittivity at 350, 270, 183, and 105 K have been observed. Using the thermally stimulated depolarization method, the temperature region of remnant polarization existence has been revealed below 270 K. It is assumed that in PCT, as well as in PbCo1/3Nb2/3O3 (PCN), in low-temperature region the phase separation caused by continuous switching of charge (valence) of Co2+/Co3+ and Ta4+/Ta5+ ions is realized.

In the frame of this study astrometric observations of an unusual object 2020 SO - a newly discovered asteroid that turned out to be a Centaur upper-stage booster from 1960s - during its two close approaches to the Earth in December, 2020 and February, 2021 were carried out using two telescopes of Pulkovo observatory. The orbit of the object in question was determined and its future orbital evolution was modelled.

The asteroid (13553) Masaakikoyama was observed with the ZA-320M and MTM-500M telescopes of the Pulkovo observatory in August and September 2018. Its axial rotation period was estimated based on the observed sections of the light curve (and additional observational data provided by B.D. Warner) at 97.2 ± 0.3 h. This estimation was made difficult by the fact that the period is commensurable with a day. The light curve has certain features suggestive of tumbling rotation and a complex shape. The orbit of (13553) Masaakikoyama was improved using the obtained astrometric positions of the asteroid.

Observations of potentially hazardous asteroid 2017 VR12 during its close approach to the Earth were made at Pulkovo Observatory via ZA-320M telescope at the end of February and the beginning of March 2018. Orbital elements of the asteroid were improved basing on the obtained astrometric data. The orbital evolution was studied and the influence of non-gravitational effects was estimated. The axial rotation period of the asteroid was determined from photometric data.

Astrometric and photometric observations of two near-Earth asteroids having poorly-defined axial rotation periods – Masaakikoyama (13553) and 5131 (1990 BG) – were performed using two telescopes of the Pulkovo Observatory (CAO RAS). Both asteroids in question have proved to be very slow rotators with signs of tumbling. Using the data obtained their periods were derived (97.1 ± 0.2 and 157.82 ± 0.2 hours, respectively), dense lightcurves were obtained. Accuracy of the orbital elements of the asteroids was also improved.

Astrometric and photometric observations of asteroids 276033 (2002 AJ129) and 2017 VR12 (both classified as a "Potentially Hazardous Asteroids" by the Minor Planet Center) were made using two telescopes of the Pulkovo Observatory (CAO RAS). The data was processed and the lightcurves of the objects were obtained. Accuracy of the orbital elements of the asteroids was estimated on the basis of the data obtained and the data from the Minor Planet Center.

The use of surface active liquids facilitates intense stratification of mechanically strained Bi0.5Sb1.5Te3 crystallites. A Bi0.5Sb1.5Te3 heat element with specified thickness and structure is formed by layer-by-layer deposition of "thermoelectric ink" on its free surface. A heat treatment of the formed thermoelectric element in argon at a temperature of 800 K makes it possible to minimize radically the resistance of the grain boundaries introduced into its bulk.

Ground-based baseline observations of the potentially hazardous asteroid 2014 JO25 were made. The data were processed and the accuracy of the orbital elements of the asteroid was estimated on the basis of the obtained observations and the data from the Minor Planet Center. Also, the estimation of BVRI color indices of the asteroid was made.

Расслоение монокристаллов Bi 0.5 Sb 1.5 Te 3 и синтерование полученных микро-и наноразмерных пластинНовиков 1 1 Физико-технический институт им.А.Ф.Иоффе РАН, 194021 Санкт-Петербург, Россия 2 Санкт-Петербургский Академический университет РАН, 194021 Санкт-Петербург, Россия

Using the telescopes ZA-320 M and MTM-500 M of Pulkovo Observatory (Russia), we have carried out astrometric and photometric observations of the asteroid (367943) Duende (2012 DA14) immediately after its close approach to the Earth occurred on 2013 February 15. We have obtained a series of its astrometric positions, colour indices and two fragments of its light curve. By numerically integrating, we have studied the evolution of the asteroid's orbit. Also, the influence of solar radiation pressure and Yarkovsky effect on the asteroid was estimated. The fitting of the asteroid rotation model to the observed light curve indicates that during its closest approach to the Earth, it had tumbling rotation regime.

Observations of the chosen understudied asteroids of the main belt, named after astronomers of Pulkovo observatory and St.Petersburg State University (3100) Zimmerman, (3504) Kholshevnikov, (4592) Alkissia, (4619) Polyakhova were made. The data was processed and light curves of the asteroids were obtained. Axial rotation periods of the observed objects were discovered for the first time. Accuracy of the orbital elements of the asteroids was estimated on the basis of obtained observations and MPC data.

Observational Astrometry Laboratory and Ephemeris Provision Sector of Pulkovo Observatory carry out a joint multipurpose research on asteroids belonging to various groups. Astrometric and photometric observations are done using ZA–320M and MTM–500M telescopes located at Pulkovo and in Northern Caucasus mountains, correspondingly. We obtain lightcurves that allow us to determine spin parameters and shapes of asteroids. Their color indices and taxonomy classes are derived from wideband filter observations. Improvement of asteroid orbits is achieved by doing positional measurements. Orbital evolution of asteroids is modelled, taking into account also non-gravity forces, including light pressure and Yarkovsky effect. NEAs, as well as binary asteroids, take an important place in our investigations. Quasi-satellites of Venus, Earth, and Mars are new targets of our research, one of the examples being 2012DA14 that approached Earth in early 2013; many MTM–500M observations of this asteroid were obtained around the date of approach.