Icarus最新文献

{"title":"Martian Chaos terrain fracture geometry indicates drainage and compaction of laterally heterogeneous confined aquifers","authors":"Joseph S. Levy ,&nbsp;Thomas F. Subak ,&nbsp;Ian Armstrong ,&nbsp;Izzy King ,&nbsp;Lingfeng Kuang ,&nbsp;Lily Kuentz ,&nbsp;James H. Gearon ,&nbsp;Sophie Naylor ,&nbsp;M.C. Rapoza ,&nbsp;Haobo Wang","doi":"10.1016/j.icarus.2024.116377","DOIUrl":"10.1016/j.icarus.2024.116377","url":null,"abstract":"<div><div>The interlocking plateaus of martian chaotic terrain have long been inferred to relate to Hesperian outflow-channel megafloods. Numerous hypotheses have been invoked to explain the formation of the hundreds-of-kilometer-scale depressions that chaoses are found in, and the mechanisms by which the fractures formed. Hypotheses range from mechanisms involving water, e.g., ice melt, overturn of sediment-covered paleolakes, or submarine landslides, to purely magmatic processes, such as caldera formation, to exotic endmembers including clathrate decomposition. These interpretations of martian chaos are largely based on photogeological mapping of individual chaoses, and have mostly neglected analysis of the chaos fracture network and its relationships with the chaos basin. Here, we show, based on analysis of 35,964 fracture blocks across 18 different chaoses and 6 terrestrial analogs, and supported by novel volumetric measurements of chaos terrain deposits and intervening void spaces, that the geometry of martian chaoses is best explained by depressurization and compaction of an underlying confined aquifer. Block size distributions are incompatible with magma chamber collapse analog experiments. We show that sedimentary fill in chaos basins is inhomogeneously distributed, with layers thickening towards the chaos center, as in terrestrial sedimentary basins. The relationship between fracture block thickness and area is explained by the same power law that describes fracture spacing and layer thickness in weak terrestrial sandstones. The presence of some chaoses with blocks that are higher than surrounding plains implies repressurization of some sub-chaos aquifers. Hesperian-aged water or ice may remain within ∼1–3 km of the surface beneath these landforms.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116377"},"PeriodicalIF":2.5,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Librations and obliquity of the largest moons of Uranus","authors":"Rose-Marie Baland ,&nbsp;Valerio Filice ,&nbsp;Sébastien Le Maistre ,&nbsp;Antony Trinh ,&nbsp;Marie Yseboodt ,&nbsp;Tim Van Hoolst","doi":"10.1016/j.icarus.2024.116371","DOIUrl":"10.1016/j.icarus.2024.116371","url":null,"abstract":"<div><div>Following the discovery of several ocean worlds in the solar system, and the selection of Uranus as the highest priority objective by the Planetary Science and Astrobiology Decadal Survey 2023-2032, the five largest moons of Uranus (Miranda, Ariel, Umbriel, Titania and Oberon) have been receiving renewed attention as they may also harbor a subsurface ocean. We assess how rotation measurements could help confirm the internal differentiation of the bodies and detect internal oceans if any. Because of the time-varying gravitational torque of Uranus on the flattened shape of its synchronous satellites, the latter librate with respect to their mean rotation and precess with a non zero obliquity. For a range of interior models with a rocky core surrounded by a hydrosphere, either solid or divided into an outer ice shell with a liquid ocean underneath, we compute their diurnal libration amplitude and obliquity. We find that if the Uranian satellites were two-layer solid bodies, libration measurement accuracies from around 0.25 m for Oberon to around 6 m for Miranda would rule out the possibility of homogeneous interiors. In combination with independent estimates of the mean moment of inertia (MOI), libration measurements could also be used to detect the presence of an ocean, the measurement precision required for this depending on the actual value of the libration amplitude. To compute the obliquity, we first build series for the orbital precession of all five satellites with a secular perturbations model. With the exception of Miranda, we show that due to the mutual gravitational interactions between the satellites, the obliquity of the large Uranian moons exhibits relatively large periodic variations around the mean value. We find that an obliquity measurement accuracy from around 1 m for Ariel to around 400 m for Oberon can rule out the homogeneous case. The presence of an internal global ocean could allow a resonant amplification of the obliquity, facilitating its detection. If no such resonance occurs, the obliquity would be almost indistinguishable from that expected for a solid body. The effect of tidal deformations on the rotation of the small to medium-sized Uranian moons is showed to be limited. Librations would be reduced by up to 10% and obliquity increased by up to 15% for Titania and Oberon, the effects being negligible for Miranda.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116371"},"PeriodicalIF":2.5,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"A new model of crater degradation on Ceres involving ice sublimation and talus formation","authors":"N. Le Becq ,&nbsp;S.J. Conway ,&nbsp;B. Jabaud ,&nbsp;G. Tobie ,&nbsp;R. Artoni","doi":"10.1016/j.icarus.2024.116353","DOIUrl":"10.1016/j.icarus.2024.116353","url":null,"abstract":"&lt;div&gt;&lt;div&gt;We report on the widespread occurence of talus on cerean crater walls using Dawn framing camera images. This is unexpected for a planetary body with no atmosphere like Ceres since the dominant process in crater degradation was expected to be topographic diffusion associated with impact gardening, like on the Moon or Mercury. To investigate why talus deposits are so common, and whether they could be related to the particular nature of Ceres’ ice-rich crust, we mapped them over the entire surface and studied their morphological characteristics. We classified the features into three different types, indicating their degree of preservation. Our results show that there is no trend between the total surface area of talus (whatever their degree of preservation) and latitude or longitude. However, we found that talus deposits tend to be observed within deep and young impact craters, and that certain craters expose a particularly large surface area of talus deposits: Dantu, Ninsar, Occator, Kupalo and Juling craters. It was also noted that well-preserved talus have a larger surface area than more degraded ones, and have &lt;span&gt;&lt;math&gt;&lt;mo&gt;≈&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt;20 % more consolidated outcrops per km&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;. Age estimates from crater size frequency distributions for the host craters completed these observations, giving a mean age of &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; Ma for the craters hosting the more preserved talus deposits, and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;28&lt;/mn&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;8&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;8&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; Ma for the craters hosting the more degraded ones. By studying the slope of the talus deposits, we obtained a value of the angle of repose of the cerean regolith: 34.5°&lt;span&gt;&lt;math&gt;&lt;mo&gt;±&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; 2.8°. We also found that the talus facing the poles are approximately 5°steeper than those facing the equator, have an 18 % larger surface area, and exhibit three times as many outcrops compared to talus on crater walls facing other directions. This suggests that the degradation of outcrops, the source of the material making up the scree, is sensitive to insolation. If we assume that the outcrops are made cohesive by the ice they contain, then we can conclude that sublimation of this ice leads to their fragmentation, at the origin of the talus material. We suggest that outcrop wall retreat due to ice sublimation feeding talus slopes is a predominant process in the earlier phase of crater degradation on Ceres supplanting impact gardening and topographic diffusion for some tens of million years. Once the maximum extent of the talus is reached, the progressively reduced debris production leads to a decreasing talus activity. Impact gardening then takes over and talus deposits are slo","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"428 ","pages":"Article 116353"},"PeriodicalIF":2.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Relationships between lobate debris aprons and lineated valley fill on Mars: Evidence for an extensive Amazonian valley glacial landsystem in Mamers Valles","authors":"Lukas Wueller ,&nbsp;James W. Head ,&nbsp;Erica R. Jawin ,&nbsp;Thomas Heyer ,&nbsp;Harald Hiesinger ,&nbsp;Carolyn H. van der Bogert","doi":"10.1016/j.icarus.2024.116373","DOIUrl":"10.1016/j.icarus.2024.116373","url":null,"abstract":"<div><div>We examine the characteristics and relationships of Lineated Valley Fill (LVF) and Lobate Debris Aprons (LDA) in Mamers Valles on Mars, a ∼950 km-long fretted valley at the dichotomy boundary. The relationships and distinctions between these glacial landforms are established by detailed analysis of LDA/LVF morphology, topography, and related features are assessed to understand their origin and modification. We document the transition from unconfined LDA to compressed and folded LVF and vice versa, implying that LDA and LVF are intimately related in morphology and mode of origin. Linear LDA dominate Mamers Valles, originating from alcoves, theater-like remnant crater rims, and tributary valleys, while circumferential LDA are arrayed around isolated mesas. Narrow valley areas display the convergence of lobes originating from either side, forming parallel linear ridges that deform into complex folds and become LVF, typically in a local and regional downvalley direction. In contrast, when LVF flows out of a topographically confined area, the material forms a piedmont-like LDA. Thus, local topography is the primary factor in determining whether a deposit will appear LVF-like, LDA-like, or have characteristics of both. Superimposed crater morphology and ground-penetrating radar data suggest the current presence of subsurface ice protected by ∼15–20 m of sublimation lag deposits, with minimal deformation and flow since superposed crater formation. Regional integration leads to the interpretation that the LDA-LVF exposures and ice entry points into the fretted valleys represent the waning stages of a more widespread regional Amazonian plateau glacial landsystem that occupied fretted terrain valleys formed earlier in the Late Noachian-Early Hesperian.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116373"},"PeriodicalIF":2.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Debiasing astro-photometric observations with corrections using statistics (DePhOCUS)","authors":"Tobias Hoffmann ,&nbsp;Marco Micheli ,&nbsp;Juan Luis Cano ,&nbsp;Maxime Devogèle ,&nbsp;Davide Farnocchia ,&nbsp;Petr Pravec ,&nbsp;Peter Vereš ,&nbsp;Björn Poppe","doi":"10.1016/j.icarus.2024.116366","DOIUrl":"10.1016/j.icarus.2024.116366","url":null,"abstract":"<div><div>Photometric measurements allow the determination of an asteroid’s absolute magnitude, which often represents the sole means to infer its size. Photometric observations can be obtained in a variety of filters that can be unique to a specific observatory. Those observations are then calibrated into specific bands with respect to reference star catalogs. In order to combine all the different measurements for evaluation, photometric observations need to be converted to a common band, typically V-band. Current band-correction schemes in use by IAU’s Minor Planet Center (MPC), JPL’s Center for Near Earth Object Studies (CNEOS) and ESA’s NEO Coordination Centre (NEOCC) use average correction values for the apparent magnitude derived from photometry of asteroids as the corrections are dependent on the typically unknown spectrum of the object to be corrected. By statistically analyzing the photometric residuals of asteroids, we develop a new photometric correction scheme that does not only consider the band, but also accounts for reference catalog and observatory. We analyzed nearly 500<!--> <!-->000 observations submitted to the MPC from 468 asteroids with published and independently determined high confidence <span><math><mi>H</mi></math></span> and <span><math><mi>G</mi></math></span> values. We describe a new statistical photometry correction scheme for asteroid observations with debiased corrections. Testing this scheme on a reference group of asteroids, we see a 36% reduction in the photometric residuals. Moreover, the new scheme leads to a more accurate and debiased determination of the <span><math><mi>H</mi></math></span>-<span><math><mi>G</mi></math></span> magnitude system and, in turn, to more reliable inferred sizes. We discuss the significant shift in the corrections with this “DePhOCUS” debiasing system, its limitations, and the impact for photometric and physical properties of all asteroids, especially Near-Earth Objects.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116366"},"PeriodicalIF":2.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"How might a planet between Mars and Jupiter influence the inner solar system? effects on orbital motion, obliquity, and eccentricity","authors":"Emily Simpson ,&nbsp;Howard Chen","doi":"10.1016/j.icarus.2024.116364","DOIUrl":"10.1016/j.icarus.2024.116364","url":null,"abstract":"<div><div>As implied by exoplanet population censuses, super-Earths are extremely common in the galaxy. In the solar system, models suggest that the formation of an Earth-to-super-Earth mass planet could have readily occurred in the inner regions (<span><math><mrow><mo>&lt;</mo><mn>3</mn></mrow></math></span> AU) if such body is able to survive the early intense and chaotic intertaction episodes of the Jovian worlds with the rest of the solar system. In this study, we test the consequences of such a hypothesis using a three-dimensional (3D) N-Rigid-Body integrator. With a 3D model in which the planet is modeled as a rigid body to account for its finite size and rotation, we simulate the orbital evolution of the three inner terrestrial planets over 2 Myr periods. Our results show that an additional super-Earth sized planet between 2 and 3.5 AU would have (i) destabilized Earth’s orbit over timescales of 1-2 Myrs, (ii) increased Mars’s obliquity by <span><math><mrow><mo>∼</mo><mn>55</mn><mo>°</mo></mrow></math></span>, and (iii) perturbed the eccentricity of Venus by up to <span><math><mrow><mi>e</mi><mo>∼</mo><mn>0</mn><mo>.</mo><mn>4</mn></mrow></math></span>. Our study explores an “alternate fate” of the terrestrial planets and our results suggest that the formation of a super-Earth in the inner solar system would have exerted grave consequences for the orbital dynamics and habitability of the terrestrial planets.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116364"},"PeriodicalIF":2.5,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 characterization of the early-season dust storm of Mars year 36","authors":"C. Martín-Rubio,&nbsp;A. Vicente-Retortillo,&nbsp;G. Martínez-Esteve,&nbsp;F. Gómez,&nbsp;J.A. Rodríguez-Manfredi","doi":"10.1016/j.icarus.2024.116369","DOIUrl":"10.1016/j.icarus.2024.116369","url":null,"abstract":"<div><div>Dust storms are one of the most important dust transport mechanisms on Mars with significant impacts on temperatures and atmospheric dynamics. Regional storms generally occur during the spring and summer of the southern hemisphere, but some of them have been observed earlier in the year. While these early-season storms have been little studied over the years, their occurrence produces important dust liftings. Their study, both vertically and horizontally, allows us to understand the mechanism of dust distribution that initiates them and the areas in which their onset takes place. In this study we compare the dust patterns of the early storms of MY 29 and 36. In addition, we analyzed globally, in each longitude, the early storm that occurred in MY 36 which was the most intense detected in such an early time. It presents maximum values of column dust optical depth (CDOD) of 0.5 and temperatures of 197 K. We use dust and temperature measurements provided by the Mars Climate Sounder (MCS) instrument and images by the Mars Color Imager (MARCI), both on board Mars Reconnaissance Orbiter (MRO).</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116369"},"PeriodicalIF":2.5,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Identification of candidate martian maars in Arena Colles and Nephentes/Amenthes with extension to maars as a proxy for past ground water/ice depths","authors":"Alison H. Graettinger,&nbsp;Julia Boyd,&nbsp;Joseph A. Nolan","doi":"10.1016/j.icarus.2024.116368","DOIUrl":"10.1016/j.icarus.2024.116368","url":null,"abstract":"<div><div>Maar craters represent the top of a volcanic construct produced by subsurface explosive interactions between ground water/ice and rising magma. Recent comprehensive studies of terrestrial maars have established the commonality of complex maar crater geometries composed of overlapping circular components with a single near continuous outer rim. These distinctive geometries, and the availability of high spatial resolution visible imagery on Mars, provide an opportunity to identify and evaluate candidate maars on Mars. This study evaluated 49 closed depressions in Arena Colles and Nephentes/Amenthes based on their proximity to pitted cones of proposed volcanic origin. Across the two regions, 13 candidate maars were recognized for their similarity to terrestrial maars in absence of any exclusionary characteristics related to other formation processes such as butterfly ejecta around binary craters. The recognition of maars on Mars would provide additional proxies for the presence and range of depths for ground water and ice at the time of eruption. The diameter of the multiple overlapping circular components in maar craters can be used to provide first order estimates of the depths of the underlying diatreme as a proxy for depth of explosions and thus presence of water in the subsurface. Estimates based on the circular components of the 13 candidate maars recognized here indicate that water/ice depths at the time of formation would be between 0.6 and 4 km.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116368"},"PeriodicalIF":2.5,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"3D morphometry of Martian craters from HRSC DEMs using a multi-scale semantic segmentation network and morphological analysis","authors":"Peiqi Ye ,&nbsp;Rong Huang ,&nbsp;Yusheng Xu ,&nbsp;Wendi Li ,&nbsp;Zhen Ye ,&nbsp;Xiaohua Tong","doi":"10.1016/j.icarus.2024.116358","DOIUrl":"10.1016/j.icarus.2024.116358","url":null,"abstract":"<div><div>The morphology of impact craters reveals the structure and composition of the Martian surface, especially the subsurface conditions and Martian geological history, which have increasing importance in Mars exploration missions. This work presents a 3D morphometric method for detecting and delineating Martian craters, and a 3D morphological analysis was conducted. Specifically, this work first focused on the segmentation of Martian craters. Based on the segmentation results, clustering of crater instances was then carried out. Finally, with the individual craters that were extracted, a morphological analysis involving the measurements of their diameter, depth, area, RMS height, rim height, circularity, and the statistics thereof was performed. Unlike previous studies, which have mainly used optical images and object detection approaches, this work regards crater extraction as a semantic segmentation task instead of an object detection task to better delineate the precise shape and boundary information. Digital elevation model (DEM) was utilized as primary data to directly obtain 3D information, which was converted into 3D point cloud format and fed to a multi-scale semantic segmentation network. The semantic segmentation results achieved an overall accuracy of 0.932 and mIOU of 0.871 on the test data. We automatically counted 63 craters in Noachis Terra and 40 craters in Terra Cimmeria. The 3D morphological measurements showed that 66% of the impact craters in the first region were larger than 10 km in diameter, while 50% of the impact craters in the second region were larger than 10 km. In both areas, craters could reach a maximum depth of 2000 m. With the proposed method, we can automatically conduct 3D morphological measurements of Martian craters with high efficiency that is improved by 15 times compared with that of manual crater analysis tools. The achieved 3D morphometric results can provide a reference and support for future research on Martian landforms.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116358"},"PeriodicalIF":2.5,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Maximum dust-to-gas mass flux ratio in spherically expanding dusty-gas flow","authors":"V.V. Zakharov ,&nbsp;N.Y. Bykov ,&nbsp;A. Rotundi ,&nbsp;A.V. Rodionov ,&nbsp;V. Della Corte ,&nbsp;S.L. Ivanovski","doi":"10.1016/j.icarus.2024.116363","DOIUrl":"10.1016/j.icarus.2024.116363","url":null,"abstract":"<div><div>In this paper, we consider the motion of a solid spherical particle in a spherically expanding gas flow as an elementary model of the gas-dust atmosphere of a comet. Based on the results of numerical simulations we propose an approximation for the terminal dust velocity and an estimate of the maximum dust-to-gas mass flux ratio (in a dusty-gas flow with the dust size distribution given by a power law) which is consistent with assumption of negligible impact of dust on the gas flow (frequently used in simulations of dusty gas flows).</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116363"},"PeriodicalIF":2.5,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}