Solar System Research最新文献

{"title":"Disturbances in the Rotational Dynamics of Asteroid (99942) Apophis at its Approach to the Earth in 2029","authors":"K. S. Lobanova,&nbsp;A. V. Melnikov","doi":"10.1134/S0038094623700107","DOIUrl":"10.1134/S0038094623700107","url":null,"abstract":"<p>Using numerical modeling of the rotational dynamics of asteroid (99942) Apophis, the disturbances that occur in the rotational motion of asteroids during their close approaches to the Earth were studied. Such events can lead to significant changes in the speed of the asteroid’s own rotation and the orientation of its rotation axis in space. Assuming that the figure of Apophis is approximated by a triaxial ellipsoid, the dependences of changes in the rotation period of an asteroid on the parameters of the orbit and its rotational state before approaching the Earth were studied. It has been established that the rotation period of Apophis, which is currently about 30 h, may change due to the next approach to Earth in 2029 very significantly—to 10–15 h; in numerical experiments, both acceleration and deceleration of the asteroid’s rotation were observed. Perturbations in the rotational motion of the asteroid noticeably affect its further orbital dynamics as a result of changes in the magnitude of the Yarkovsky effect. It was concluded that as a result of close approach, the average rate of change of the semimajor axis of Apophis’s orbit caused by the Yarkovsky effect, which is currently about 200 m/year, may decrease to 160 m/year or increase to 300 m/year.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 2","pages":"208 - 219"},"PeriodicalIF":0.6,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150717","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 Acoustic Wave Phenomena in Radiation Magnetic Hydrodynamics","authors":"A. V. Kolesnichenko","doi":"10.1134/S0038094623700077","DOIUrl":"10.1134/S0038094623700077","url":null,"abstract":"<p>The propagation of linear acoustic disturbances in an infinite, homogeneous, gray radiating plasma, initially in mechanical and radiation equilibrium, is considered. An exact governing equation for radiation acoustics in a radiating gray gas is derived, taking into account the influence of the transverse magnetic field. Radiation magnetohydrodynamics (MHD) is described by three hydrodynamic equations and two radiative momentum equations, making extensive use of the formalism of radiation thermodynamics. With the aim of more reliably describing the evolution of radiation magnetic–acoustic disturbance waves with scattering and attenuation, the conditions of radiation-thermal dissipation, the force of radiation resistance, as well as magnetic force and Joule heat are introduced into these equations. In this case, the Eddington approximation is used, which allows one to study the modes of radiation magnetohydrodynamic waves in two asymptotic cases—optically thin and thick gas. The exact control equation derived in the work made it possible, using the heuristic Whitham method, to obtain a set of approximate control equations of the lowest order, each of which is part of a reliable approximation to the exact equation in a certain region of the independent time variable. The relatively simple form of such equations made it possible to study the physical processes occurring in each radiation magnetic–acoustic wave without a formal solution to the full problem.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 2","pages":"250 - 262"},"PeriodicalIF":0.6,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150785","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":"Simulation Experiments on the Deposition of Charged Particles of LMS-1D Regolith on the Solar Panels of Spacecraft","authors":"A. S. Sokolov,&nbsp;T. E. Gayanova,&nbsp;V. D. Borzosekov,&nbsp;V. D. Stepakhin,&nbsp;A. K. Kozak,&nbsp;E. A. Obraztsova,&nbsp;N. T. Vagapova,&nbsp;I. V. Badurin,&nbsp;E. S. Loginova,&nbsp;N. N. Skvortsova","doi":"10.1134/S0038094624700114","DOIUrl":"10.1134/S0038094624700114","url":null,"abstract":"<p>The article describes simulation experiments of interaction of lunar dust with the surface of solar panels. The experiments are based on the creation of a dusty plasma cloud, when the radiation of a powerful pulsed gyrotron is exposed to a substance that simulates lunar dust. This approach was tested using a lunar regolith simulator. The analysis of the results of deposition of charged regolith particles on solar panels of different types and changes in their efficiency is presented.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 3","pages":"282 - 288"},"PeriodicalIF":0.6,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141121973","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":"Wind Speed Variations at the Venus Cloud Top above Aphrodite Terra According to Long-term UV Observations by VMC/VENUS Express and UVI/AKATSUKI","authors":"M. V. Patsaeva,&nbsp;I. V. Khatuntsev,&nbsp;D. V. Titov,&nbsp;N. I. Ignatiev,&nbsp;L. V. Zasova,&nbsp;D. A. Gorinov,&nbsp;A. V. Turin","doi":"10.1134/S0038094623700053","DOIUrl":"10.1134/S0038094623700053","url":null,"abstract":"<p>Series of consecutive UV (365 nm) images of Venus cloud coverage provide a way to investigate dynamics of the mesosphere. An unprecedented series of such images was obtained by the VMC/Venus Express (ESA) and UVI/Akatsuki (JAXA) cameras from 2006 to 2022. At 10°S long-term variations in the mean zonal and meridional wind speed are observed with a period of 12.5 ± 0.5 years. Analysis of the of the mean zonal wind behavior around noon (12 ± 1 h) at phase angles of 60°–90° in limited observation time intervals shows that near the minimum of the long-term dependence the deceleration of the horizontal flow is observed above the highest part of Aphrodite Terra, Ovda Regio, for both VMC and UVI. Conversely, acceleration is observed above the Ovda Regio near the maximum of the long-term dependence. The considered longitudinal variations of the zonal wind speed extend from the equator to middle latitudes (0°–40°). The meridional wind speed shows longitudinal variations associated with the topography of the underlying surface, regardless of whether the horizontal flow is slowing down or accelerating above the highlands of Aphrodite Terra.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 2","pages":"148 - 162"},"PeriodicalIF":0.6,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0038094623700053.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Hydrogen Concentrations in a Tectonically Deformed Impact Crater in the Area of the South Pole of the Moon","authors":"A. B. Sanin,&nbsp;I. G. Mitrofanov,&nbsp;A. T. Bazilevsky,&nbsp;M. L. Litvak,&nbsp;M. V. D’yachkova","doi":"10.1134/S003809462401009X","DOIUrl":"10.1134/S003809462401009X","url":null,"abstract":"<p>The article provides a description of the crater in the marginal zone of the southern polar region of the Moon with the coordinates of the center 126.59° W, 64.32° S The diameter of the crater is 34 km. It has a fractured bottom, which is considered a sign of magma intrusion into the subcrater space. The absolute age of formation of the crater under study was estimated to be ~3.85 billion years based on the spatial density of small craters superimposed on its rim. In the vicinity of the studied crater, low-iron anorthosite material is predominant. It can be argued that the basin of the crater under study is very dry compared to its surroundings. A significant loss of hydrogen/water and its redistribution from the bottom of the crater to the area around the crater could be caused by reworking of the surface due to the intrusion of magma under the crater, traces of which can be traced by the presence of cracks on the bottom of the crater.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"88 - 93"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882586","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":"Mapping Hyperion in Projections of the Triaxial Ellipsoid Based on a New Reference Network and a Digital Terrain Model","authors":"A. I. Sokolov,&nbsp;I. E. Nadezhdina,&nbsp;M. V. Nyrtsov,&nbsp;A.E. Zubarev,&nbsp;M. E. Fleis,&nbsp;N. A. Kozlova","doi":"10.1134/S0038094624010106","DOIUrl":"10.1134/S0038094624010106","url":null,"abstract":"<p>The work used data on Saturn’s satellite Hyperion obtained from the flight results of the <i>Cassini</i> spacecraft due to their completeness, resolution, and image quality. They pointed out the chaotic nature of Hyperion’s rotation, as a result of which there was an ambiguity in determining its coordinate system associated with the body. The dimensions of the approximating ellipsoid and the parameters of the transition from the coordinate system, initially adopted under the assumption of uniform rotation of Hyperion around Saturn, to a coordinate system whose axes coincide with the axes of the found ellipsoid were obtained. A digital model of the Hyperion surface was also created, on the basis of which geodetic heights were calculated relative to a triaxial ellipsoid with certain parameters. The method for calculating heights is based on the combined use of the equation of the normal to the surface passing through a given point and the equation of the surface itself. As a result of the research, a map of Hyperion was compiled in the projection of the triaxial ellipsoid with horizontal lines constructed on the basis of calculated geodetic heights. An original method for studying the nature of Hyperion’s rotation is presented using the projection of Saturn’s position onto the surface of Hyperion for all known moments in time in an object-centric coordinate system. The implementation of this technique allowed us to assume that Hyperion’s own rotation axis precesses relative to the largest axis of the body in a counterclockwise direction.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"112 - 121"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882675","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":"Growth of the Moon Due To Bodies Ejected from the Earth","authors":"S. I. Ipatov","doi":"10.1134/S0038094624010040","DOIUrl":"10.1134/S0038094624010040","url":null,"abstract":"<p>The evolution of the orbits of bodies ejected from the Earth has been studied at the stage of its accumulation and early evolution after impacts of large planetesimals. In the considered variants of calculations of the motion of bodies ejected from the Earth, most of the bodies left the Hill sphere of the Earth and moved in heliocentric orbits. Their dynamical lifetime reached several hundred million years. At higher ejection velocities <i>v</i>_ej the probabilities of collisions of bodies with the Earth and Moon were generally lower. Over the entire considered time interval at the ejection velocity <i>v</i>_ej, equal to 11.5, 12 and 14 km/s, the values of the probability of a collision of a body with the Earth were approximately 0.3, 0.2 and 0.15–0.2, respectively. At ejection velocities <i>v</i>_ej ≤ 11.25 km/s, i.e., slightly exceeding a parabolic velocity, most of the ejected bodies fell back to the Earth. The probability of a collision of a body ejected from the Earth with the Moon moving in its present orbit was approximately 15–35 times less than that with the Earth at <i>v</i>_ej ≥ 11.5 km/s. The probability of a collision of such bodies with the Moon was mainly about 0.004–0.008 at ejection velocities of at least 14 km/s and about 0.006–0.01 at <i>v</i>_ej = 12 km/s. It was larger at lower ejection velocities and was in the range of 0.01–0.02 at <i>v</i>_ej = 11.3 km/s. The Moon may contain material ejected from the Earth during the accumulation of the Earth and during the late heavy bombardment. At the same time, as obtained in our calculations, the bodies ejected from the Earth and falling on the Moon embryo would not be enough for the Moon to grow to its present mass from a small embryo moving along the present orbit of the Moon. This result argues in favor of the formation of a lunar embryo and its further growth to most of the present mass of the Moon near the Earth. It seems more likely to us that the initial embryo of the Moon with a mass of no more than 0.1 of the mass of the Moon was formed simultaneously with the embryo of the Earth from a common rarefied condensation. For more efficient growth of the Moon embryo, it is desirable that during some collisions of impactor bodies with the Earth, the ejected bodies do not simply fly out of the crater, but some of the matter goes into orbits around the Earth, as in the multi-impact model. The average velocity of collisions of ejected bodies with the Earth is greater at a greater ejection velocity. The values of these collision velocities were about 13, 14–15, 14–16, 14–20, 14–25 km/s with ejection velocities equal to 11.3, 11.5, 12, 14 and 16.4 km/s, respectively. The velocities of collisions of bodies with the Moon were also higher at high ejection velocities and were mainly in the range of 7–8, 10–12, 10–16 and 11–20 km/s at <i>v</i>_ej, equal to 11.3, 12, 14 and 16.4 km/s, respectively.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"94 - 111"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882770","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":"Behavior of Sulfur by the Example of Iron Balls from Regolith Samples from Luna-24 (Mare Crisium)","authors":"A. V. Mokhov,&nbsp;A. P. Rybchuk,&nbsp;T. A. Gornostaeva,&nbsp;P. M. Kartashov","doi":"10.1134/S0038094624010076","DOIUrl":"10.1134/S0038094624010076","url":null,"abstract":"<p>Studies of lunar regolith delivered to Earth by the Soviet automatic station (AS) <i>Luna-24</i> using highly local electron microscopy methods made it possible to obtain data confirming the migration of sulfur during cooling of metal melts during the process of liquation. As a result, local Fe-S concentrates are formed, and part of the sulfur is displaced outward, forming sulfur shells on the surface of the melt droplets. Their formation on the surface is associated with the evaporation-condensation process during the cooling process of iron balls. The resulting sulfur coatings can be preserved if they are preserved in glass or under thin films of silicate condensate.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"68 - 77"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882663","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":"Some Aspects of the Relativistic Rotation of Solar System Bodies using the Example of Jupiter and its Galilean Satellites","authors":"V. V. Pashkevich,&nbsp;A. N. Vershkov","doi":"10.1134/S0038094624010088","DOIUrl":"10.1134/S0038094624010088","url":null,"abstract":"<p>This paper is devoted to some aspects of the study of relativistic effects (geodetic precession and geodetic nutation, which together constitute geodetic rotation) in the rotation of celestial bodies of the Solar System using the example of Jupiter and its Galilean satellites (Io, Europa, Ganymede, and Callisto). The difference in the angular velocity vectors of geodetic rotation is shown depending on the choice of reference frame. Thus, the absolute value of the angular velocity vector of the geodetic rotation of the satellite under study relative to the barycenter of the Solar System will not coincide with the absolute value of a similar vector of the satellite under study relative to the barycenter of the planet’s satellite system. As a result, the most significant secular and periodic terms of geodetic rotation were determined for the first time: a) of Jupiter and its Galilean satellites in terms of the Euler angles, in the perturbing terms of physical libration and in the absolute value of the angular rotation vector of the geodetic rotation of the body under study relative to the barycenter of the Solar System and the plane of the mean orbit of Jupiter of the epoch J2000.0; b) of Galilean satellites of Jupiter in the perturbing terms of physical libration and the absolute value of the angular rotation vector of the geodetic rotation of the studied body relative to the barycenter of the Galilean satellite system of Jupiter and the mean orbit plane of the studied Galilean satellite of the epoch J2000.0. The obtained analytical values of the geodetic rotation of the studied objects can be used for a numerical study of their rotation in the relativistic approximation, and also used to evaluate the influence of relativistic effects on the orbital–rotational dynamics of bodies of exoplanetary systems.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"122 - 140"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882676","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":"Coronae–Sources of Young Volcanism on Venus: Topographic Features and Estimates of Productivity","authors":"E. N. Guseva,&nbsp;M. A. Ivanov","doi":"10.1134/S0038094624010039","DOIUrl":"10.1134/S0038094624010039","url":null,"abstract":"<p>Our study of the spatial and genetic relationship between coronae and lobate plains allows us to draw two important conclusions. (1) About 17% of all volcanic coronae of Venus are sources (coronae–sources) of young lavas that form lobate plains of the Atlian period. A small portion of coronae–sources in the total population of coronae reflects the decrease in the formation rate of mantle diapirs. (2) The area of lobate plains associated with a particular corona and the area of the corona itself are negatively correlated. These relationships allow the existence of only two models for the final stages in the evolution of mantle diapirs. Having analyzed both of these models, we suppose that, during the Atlian period in the geologic history of Venus, either a single zone of neutral buoyancy existed or the lithosphere base was located at approximately the same level.</p>","PeriodicalId":778,"journal":{"name":"Solar System Research","volume":"58 1","pages":"78 - 87"},"PeriodicalIF":0.6,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882678","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}