Kinematics and Physics of Celestial Bodies最新文献

{"title":"Electron Density Reduction Caused by the Tonga Volcano Eruption on January 15, 2022","authors":"L. F. Chernogor,&nbsp;Yu. B. Mylovanov","doi":"10.3103/S0884591323040037","DOIUrl":"10.3103/S0884591323040037","url":null,"abstract":"<p>The explosive Tonga volcano is among the unique ones. Its order of magnitude is the same as Krakatoa (1883), St. Helens (1980), El Chichón (1982), and Pinatubo (1991) volcanoes. The uniqueness of the Tonga volcano lies in the fact that the products of eruption of the Tonga volcano rose to a record height of 50–58 km, whereas the height of eruption of the most powerful Krakatoa volcano reached only 40–55 km. The Tonga volcano has estimates of 3.9 × 10¹⁸ J for thermal energy, approximately 5.8 for volcanic explosive index <i>VEI</i>, approximately 5.5 for volcano magnitude <i>M</i>, and approximately 10.8 for eruption intensity <i>I</i>. We have estimated the explosion energy to be 16–18 Mt TNT. The problems of proving that a decrease in the total electron content (TEC), which was observed on January 15, 2022, in the ionosphere, was caused by the Tonga volcano explosion, and determining the principal parameters of the ionospheric hole are very urgent problems. This study is aimed at analyzing the parameters of the ionospheric hole created by the Tonga volcano explosion on January 15, 2022. Well-known GPS technologies are used to obtain data on time variations of the ionospheric TEC in the vertical column by measuring the pseudo-range and the integrated phase data at two frequencies along the path to each GPS satellite. The space weather conditions were favorable for observing the ionospheric effects caused by the explosion of the Tonga volcano. The calendar dates of January 13 and 17, which are used as reference days, were the least disturbed ones. The main results are as follows. It was found that the TEC on the reference days varied almost monotonically. Aperiodic and quasi-periodic variations of TEC were observed on the day of volcano eruption. Aperiodic variations are associated with a decrease in the TEC. This effect is called the ionospheric hole. It has been proven that the ionospheric hole is caused by a volcanic explosion. The delay time of the hole increases with an increase in the distance between the volcano and the observation site, while both the absolute value of the TEC and the relative value of its decrease are reduced. According to estimates, the horizontal size of the ionospheric hole did not exceed 10 Mm, and the time delay of its appearance did not exceed 122 min. The vertical speed of disturbance propagation was 36–72 m/s, and the horizontal speed was 2.2 km/s. The lifetime of the ionospheric hole was 120–200 min. The TEC in the ionospheric hole was reduced by approximately 2.5–10 TECU, which is a function of the distance from the volcano to the observation site, and the relative decrease ranged from –17 to –34%.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 4","pages":"204 - 216"},"PeriodicalIF":0.5,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4152956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic-Gravity Wave Spectrum Filtering in the Horizontally Inhomogeneous Atmospheric Flow","authors":"A. K. Fedorenko,&nbsp;E. I. Kryuchkov,&nbsp;O. K. Cheremnykh,&nbsp;I. T. Zhuk","doi":"10.3103/S0884591323040049","DOIUrl":"10.3103/S0884591323040049","url":null,"abstract":"<div><div><h3>\u0000 <b>Abstract</b>—</h3><p>The properties of acoustic-gravity waves (AGWs) in the atmosphere can be determined to a greater extent by the features of the propagation medium than by the sources of these disturbances. In the presence of spatial inhomogeneities of atmospheric parameters, significant deviations of AGW characteristics from theory are observed. This complicates the experimental diagnosis of waves and the search for a connection with their potential sources. AGW observations from the Dynamics Explorer 2 satellite indicates the predominance of waves with certain spectral characteristics in the polar thermosphere. It has been found that AGWs with large amplitudes are spatially consistent with areas of strong winds, while AGWs move mainly toward the wind. In order to explain the observed AGW properties, we investigate the filtering of the spectrum of these waves in the presence of a spatially inhomogeneous wind. It is shown that the direction and magnitude of the wave vector change in a special way in the oncoming inhomogeneous wind. In this case, with an increase in the speed of the headwind, the wave vector gradually tilts toward the horizontal plane. The vertical component of the wave vector decreases rapidly, and its horizontal component tends to some threshold value, which is predominant in observations. In addition, in the oncoming inhomogeneous flow, the frequencies and amplitudes of the waves increase. As a result, high-frequency wave harmonics with a small angle of inclination of the wave vector to the horizontal plane and a characteristic horizontal wavelength will prevail in a strong headwind from the continuous spectrum of atmospheric AGWs that can be generated by a hypothetical source. Since the wave vector and the group velocity vector in AGWs are almost perpendicular to each other, such waves provide efficient energy transfer in the vertical direction. In this regard, AGWs play an important role in the energy balance of the polar atmosphere by redistributing the energy of horizontal wind currents in the vertical direction.</p></div></div>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 4","pages":"217 - 224"},"PeriodicalIF":0.5,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4150199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting the Maximum of Solar Cycle 25: Total Power at the Cycle’s Beginning and in the Previous Cycle as Precursor","authors":"M. I. Pishkalo,&nbsp;I. E. Vasiljeva","doi":"10.3103/S0884591323040062","DOIUrl":"10.3103/S0884591323040062","url":null,"abstract":"<div><div><h3>\u0000 <b>Abstract</b>—</h3><p>Solar activity, the most famous manifestation of which is sunspots, varies with a period of approximately 11 years. Two 11-year cycles form the 22-year magnetic cycle of the Sun. Changes in solar activity lead to changes in the interplanetary and the near-Earth space and affect the Earth and the human environment. The ability to predict solar activity in advance is important both for some practical tasks of cosmonautics and for a better understanding of the nature of those physical processes at the Sun which are responsible for the solar activity. In the work, the interrelationship of the powers (sum of the monthly sunspot numbers in the cycle) of pairs of “even-numbered to odd-numbered” and “odd-numbered to even-numbered” cycles was investigated, and an attempt was made to forecast the maximum of the current solar cycle 25, which began in December 2019, using the value of the total power of the previous solar cycle 24. It was found that there is a significant correlation between the power and amplitude of the odd-numbered cycle and the power of the previous even-numbered cycle (<i>r</i> = 0.897, <i>p</i> = 0.00043 and <i>r</i> = 0.785, <i>p</i> = 0.00715, respectively; if excluding the pair of cycles four to five). A slightly smaller correlation is observed between the amplitude of the odd-numbered cycle and the amplitude of the previous even-numbered cycle (<i>r</i> = 0.712, <i>p</i> = 0.0209). Regression equations between the relevant parameters were found. The calculated predicted amplitude of solar cycle 25 is 155.6 ± 42.4 for August 2024 or 172.1 ± 46.5 for June 2024 if the power of solar cycle 24 or its maximal amplitude is used as precursor, respectively. For solar cycles 12 to 24, the relationship of the same parameters was investigated separately in the <i>N</i>- and <i>S</i>-hemispheres. It was also found that the southern hemisphere will be slightly more active than the northern one in solar cycle 25; the predicted maximal amplitudes in the <i>N</i>- and <i>S</i>-hemispheres are 86.9 ± 41.1 and 91.7 ± 29.7, respectively. The power of the solar cycle for the first 30 months from its start is closely correlated (<i>r</i> = 0.83, <i>р</i> = 5 × 10^–7) both with the amplitude of the next maximum of the cycle and with the duration of the rising phase of the cycle. This makes it possible to obtain, in the authors' opinion, the most probable forecast of the maximum of solar cycle 25 for today, i.e., 136 ± 36 for February 2025. All predictions obtained in this work indicate that solar cycle 25 will be stronger than the previous solar cycle 24.</p></div></div>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 4","pages":"225 - 238"},"PeriodicalIF":0.5,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4152954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of the Astroclimatic Conditions of the Observation Complex at the Institute of Astronomy of Kharkiv National University","authors":"A. V. Golubaev,&nbsp;A. P. Zheleznyak,&nbsp;V. G. Kaydash","doi":"10.3103/S0884591323040050","DOIUrl":"10.3103/S0884591323040050","url":null,"abstract":"<div><div><h3>\u0000 <b>Abstract</b>—</h3><p>The article is devoted to the comparison of modern astroclimatic conditions (light pollution and the number of cloudless nights) of 14 Ukrainian astronomical observatories. The aim of the work is to assess the prospects for further development of the observational complex of the Chuhuiv Observational Station (COS) at the Institute of Astronomy of Kharkiv National University (IA KNU). The level of light pollution at the selected observation stations is studied using the Global Light Pollution Map databank. The Weather Archive database is used to analyze the statistics of cloudless skies at these locations. An independent measurement of the integral brightness of the sky background is carried out using a portable integrated photometer. It is found that, in terms of light pollution, the COS of the Institute of Astronomy has the most favorable conditions for astronomical observations among other observatories in Ukraine. The results of measurements of the integrated brightness of the sky background at the COS of the Institute of Astronomy using a portable integrated photometer showed a rather dark sky background for a plain observatory; the levels of indicators are similar to the Crimean Astrophysical Observatory. A selective analysis of the weather archive database for the period 2017–2019 for the southern, western, eastern, and central regions of Ukraine showed that, on average, the statistical indicators of cloudless skies in these locations differ little. Taking into account the results of astroclimatic studies and the absence of sources of significant light pollution at distances of 15…20 km from the COS (and the low probability of their appearance in the near future), it can be concluded that it is advisable to modernize the observatory complex of the IA KNU, in particular, to build a modern telescope of 1…2-m class on its territory.</p></div></div>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 4","pages":"239 - 245"},"PeriodicalIF":0.5,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4153470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global Variations of the Total Electron Content in the Equatorial Ionosphere during the Annular Solar Eclipse of June 21, 2020","authors":"L. F. Chernogor,&nbsp;Yu. B. Mylovanov","doi":"10.3103/S0884591323040025","DOIUrl":"10.3103/S0884591323040025","url":null,"abstract":"<p>A solar eclipse (SE) causes recordable disturbances in all subsystems of the Earth–atmosphere–ionosphere–magnetosphere system and in geophysical fields. The response of the system to an SE substantially depends on the eclipse magnitude, the solar cycle phase, the atmospheric and space weather, the season, the time, and the observation coordinates. Manifestations of the response are also influenced by the observation technique. Despite the fact that the effect of a solar eclipse on the ionosphere has been studied for approximately 100 years, a number of unresolved issues remain. The purpose of this study is to describe the results of our analysis of temporal total electron content (TEC) variations caused by the annular solar eclipse on June 21, 2020, in the equatorial ionosphere. The authors analyzed 132 time dependences of the TEC that covered an extensive region with an eclipse. The maximum magnitude (<i>M</i>_max = 0.9940) of the eclipse, which began at 06:39:59 UT, was observed in northern India in Uttarakhand and lasted 38 s. Space weather conditions on June 21, 2020, were favorable for studying the effects associated with the SE. To reveal the response of the ionosphere to the annular SE on June 21, 2020, the GPS signal recordings were processed. Time variations of the TEC in the ionosphere on reference days and on the SE day of June 21, 2020, were analyzed on a global scale. For this purpose, the results of measurements at twelve stations and eleven GPS satellites were used. The dependences of the absolute and relative TEC value decreases caused by the SE on a time of day are studied. The lowest value of the TEC decrease (–2…–3 TECU) was observed in the morning. In the daytime and in the evening hours, it reached –4…–6 TECU. The relative decrease in the TEC barely depended on a time of day and reached –30…–35%. No stable dependence of the TEC decrease on the eclipse magnitude was found. The relative value of the TEC decrease depended on the SE magnitude, i.e., smaller values of the SE magnitude corresponded to smaller values of the relative TEC decrease. The duration of the TEC reduction exceeded the duration of the eclipse by 1.5–2.5 h. The time of reaching the minimum TEC values in the daytime and the evening hours delayed by 10–20 min with respect to the time of reaching the maximum SE magnitude. Wave-like disturbances of the TEC were practically absent. Undisturbed TEC values and the TEC values disturbed by the eclipse substantially depended on the location of stations and the trajectory of satellites, which was associated with the influence of equatorial ionization anomaly. This is the main peculiarity of ionospheric effects of the SE at latitudes 0°–30° N.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 4","pages":"181 - 203"},"PeriodicalIF":0.5,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4153466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of GNSS Observations (GPS Weeks 1934–2105) for the Propagation of the IGS14 Reference Frame on the Territory of Ukraine","authors":"O. Khoda","doi":"10.3103/S0884591323030054","DOIUrl":"10.3103/S0884591323030054","url":null,"abstract":"<p>From January 29, 2017 to May 16, 2020 (GPS weeks 1934–2105) all products of the International GNSS Service (IGS)–precise ephemerides of GPS and GLONASS satellites, coordinates and velocities of permanent GNSS stations, etc.–were based on the IGS14 reference frame, the first IGS realization of the release of the International Terrestrial Reference Frame ITRF2014. Observations of GNSS satellites at permanent stations located in Ukraine and in the Eastern Europe for this period were processed in the GNSS Data Analysis Centre of the Main Astronomical Observatory NAS of Ukraine (MAO). The processing was carried out with the <i>Bernese GNSS Software ver. 5.2</i> according to the requirements of the EUREF Permanent GNSS Network (EPN), that were relevant at that time. In total, observations on 277 GNSS stations, including 205 Ukrainian stations belonging to the following operators of GNSS networks: MAO NAS of Ukraine, StateGeoCadastre of Ukraine (UPN GNSS), NU Lviv Polytechnic (GeoTerrace), PJSC System Solutions (System.NET), TNT TPI company (TNT TPI GNSS Network), Navigation and Geodetic Center (NGC.net), UA-EUPOS/ZAKPOS, E.P.S. LLC, Coordinate navigation maintenance system of Ukraine (NET.Spacecenter), Kiev Institute of Land Relations (KyivPOS), KMC LLC, were processed. The IGS14 reference frame was realized by applying No-Net-Translation conditions on the coordinates of the EPN Class A stations from the EPN C2100 catalogue. As result, the stations’ coordinates in the IGS14 reference frame and the zenith tropospheric delays for all stations were estimated. The mean repeatabilities for components of GNSS stations’ coordinates for all weeks (the characteristics of the precision of the obtained daily and weekly solutions) are in the following ranges: for the northern and eastern components – from 0.6 to 1.4 mm (average values are 0.93 and 1.00 mm respectively) with outliers for the eastern component of 2.02 and 1.55 mm for GPS weeks 2085 and 2091 respectively, for height component – from 2.0 to 5.5 mm (average value is 3.51 mm).</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 3","pages":"173 - 179"},"PeriodicalIF":0.5,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4688488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photometric Flattening Index of the Solar Corona in the Solar Cycle","authors":"M. І. Pishkalo","doi":"10.3103/S0884591323030066","DOIUrl":"10.3103/S0884591323030066","url":null,"abstract":"<p>The photometric flattening index as a quantitative characteristic of the shape of the solar corona observed during a total solar eclipse was proposed by Ludendorff in the 1930s. The work collected the values of the flattening index for 69 total solar eclipses in 1851–2020 and investigated their relationship with the parameters of the solar cycle. The value of the flattening index varies from approximately 0.3–0.4 at the cycle minimum to 0.0–0.1 at the cycle maximum. The flattening index correlates with the relative sunspot numbers and the phase of the solar cycle. The correlation coefficients between the flattening index and the daily, monthly and smoothed monthly sunspot numbers are –0.577 (<i>р</i> &lt; 4 × 10^–7), –0.595 (<i>p</i> &lt; 8 × 10^–8) and –0.598 (<i>p</i> &lt; 7 × 10^–8), respectively. The correlation coefficients between the flattening index and the phase of the solar cycle for the rising and declining phases of the cycle are –0.759 (<i>p</i> &lt; 5 × 10^–6) and 0.660 (<i>p</i> &lt; 2 × 10^–6), respectively. The observed shape of the solar corona, in particular the value of the flattening index, is determined by the global magnetic field of the Sun, mainly by its dipole component.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 3","pages":"164 - 172"},"PeriodicalIF":0.5,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4687174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Possible Source and Mechanism of Origin of the Hot Component of the Kuiper Belt","authors":"A. M. Kazantsev","doi":"10.3103/S0884591323030042","DOIUrl":"10.3103/S0884591323030042","url":null,"abstract":"<p>A mechanism for the origin of Kuiper belt (KB) bodies different from the hitherto known mechanisms is proposed. The distributions of the orbital elements of most of the bodies of the hot component of the KB are analyzed. The shape of the distributions indicates that all of these bodies could have appeared as a result of the destruction of a single massive body (Kuiper belt planet, KBP). The separation velocities of the fragments were determined mainly by the linear velocities of the parts of the KBP at different depths and latitudes. The maximum separation velocity corresponded to the linear velocity on the surface of the KBP near the equator and could be 2.4 km/s. The size of the KBP could be either slightly smaller or larger than the size of the Earth. The spin period was approximately 4 h. The KBP spin axis was inclined at a slight angle to the ecliptic plane, and it was directed toward the Sun at the time of destruction. This mechanism is in good agreement with current observational data. It can explain the large number of bodies with satellites in the KB as well as the revealed dependence of the average density of bodies on their size. According to this mechanism, the spin axes of the formed debris (primarily large ones) should be inclined at small angles to the ecliptic plane. The spin axes of the dwarf planets Pluto and Haumea are inclined to the ecliptic plane at angles of 23° and 10°, respectively. The future data on the coordinates of the poles of other large KB bodies can become the final confirmation of the proposed mechanism.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 3","pages":"154 - 163"},"PeriodicalIF":0.5,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4686000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical Effects of the Yushu Meteoroid: 3","authors":"L. F. Chernogor","doi":"10.3103/S0884591323030030","DOIUrl":"10.3103/S0884591323030030","url":null,"abstract":"<p>A comprehensive modeling of the processes in all geospheres caused by the fall and explosion of the Yushu meteoroid in the Qinghai Province (People’s Republic of China) on December 22, 2020, was performed. The magnetic, electrical, electromagnetic, ionospheric, and seismic effects, as well as the effects of acoustic-gravity waves, were estimated. It is shown that the magnetic effect of turbulence was insignificant. The magnetic effect of the ionospheric currents and the current in the meteoroid’s wake could be significant (~1 nT). Due to the capture of electrons in the field of the atmospheric gravity wave, the magnetic effect could reach the order of 1 nT. The effect of the external electric field could lead to a short-term current pulse of up to 10⁴ A. The electrostatic effect could be accompanied by the accumulation of a charge of 1–10 mC with an electric field strength of approximately 1 MV/m. The flow of electric current in the wake could lead to the emission of an electromagnetic pulse in the frequency range of approximately 10 kHz with a strength of 3–30 V/m. It was found that the electromagnetic effect of infrasound could be significant (approximately 3–20 V/m and 10–60 nT). Absorption of the shock wave at the heights of the dynamo region of the ionosphere (100–150 km) could be accompanied by the generation of secondary atmospheric gravity waves with a relative amplitude of 0.1–1. The passage of the meteoroid led to the formation of a plasma wake and to a noticeable disturbance of not only the lower but also the upper atmosphere at distances of at least 1000 km. The occurrence of an electrophonic effect seems unlikely. The possibilities of generating ion and magnetic sound by infrasound as well as gradient-drift and drift-dissipative instabilities are discussed. The magnetic, electrical, and electromagnetic effects discussed in this article partially fill in the gaps in the theory of the physical effects of meteoroids in the Earth–atmosphere–ionosphere–magnetosphere system. The magnitude of the earthquake caused by the meteoroid explosion did not exceed 2.5. The average fall rate of celestial bodies similar to the Yushu meteoroid is 0.49 year^–1.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 3","pages":"137 - 153"},"PeriodicalIF":0.5,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4687188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical Effects of the Yushu Meteoroid: 2","authors":"L. F. Chernogor","doi":"10.3103/S0884591323030029","DOIUrl":"10.3103/S0884591323030029","url":null,"abstract":"<p>A comprehensive modeling of the processes in all geospheres caused by the fall and explosion of the Yushu meteoroid in the Qinghai Province (People’s Republic of China) on December 22, 2020, was performed. Thermodynamic and plasma effects, as well as the effects of the plume and turbulence, accompanying the passage of the Yushu meteoroid were estimated. It is shown that the passage of the celestial body led to the formation of a gas and dust plume. The heated meteoroid wake cooled down for several hours. Four stages of cooling of the meteoroid wake are considered. The first of them lasted approximately 0.2 s, and the temperature of the wake decreased by half due to radiation. During the second stage (~3 s), cooling continued due to radiation and expansion of the wake, and the temperature decreased by 20%. During the third stage, which lasted 6 s, the explosion products and heated gas (thermal column) with an acceleration of approximately 30 m/s² rose at a speed of 140 m/s, and the temperature decreased by 10%. The fourth stage lasted approximately 50 s, the thermal column intensively absorbed cold air, gradually cooled, and slowed down. The maximum height of the thermal column reached 7–8 km. The explosion products (dust particles and aerosols) that were part of the thermal column were subsequently involved in three processes: slow settling to the Earth’s surface, turbulent mixing with the surrounding air, and transportation by prevailing winds around the planet. It is shown that the effect of turbulence in the meteoroid’s wake was well expressed, while magnetic turbulence had hardly any effect. The main parameters of the plasma in the wake are estimated: height dependences of the linear and volume electron densities, values of their relaxation times, particle collision frequencies, plasma specific conductivity, and relaxation times of the electron temperature. It is shown that the linear and volume electron densities in the wake at the initial moment were 10¹⁹–4 × 10²² m^–1 and 10¹⁷–10²¹ m^–3 and the plasma specific conductivity was of the order of 10³ Ω^–1m^–1. The role of the dust component of the plasma is discussed.</p>","PeriodicalId":681,"journal":{"name":"Kinematics and Physics of Celestial Bodies","volume":"39 3","pages":"123 - 136"},"PeriodicalIF":0.5,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4690084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}