Icarus最新文献

{"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":"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}

{"title":"Measurements of line parameters for 12C16O2 near λ = 1.05 μm by cavity ring-down spectrometer","authors":"Tao Yang ,&nbsp;Xianmei Qian ,&nbsp;Qiang Liu ,&nbsp;Wenyue Zhu ,&nbsp;Hongliang Ma ,&nbsp;Jianjie Zheng ,&nbsp;Chaolong Cui ,&nbsp;Xiaomei Jin ,&nbsp;Jun Huang","doi":"10.1016/j.icarus.2024.116359","DOIUrl":"10.1016/j.icarus.2024.116359","url":null,"abstract":"<div><div>The absorption spectra of ¹²C¹⁶O₂ within the wavenumber range of 9358–9648 cm⁻¹ have been precisely measured using a continuous-wave cavity ring-down spectrometer at room temperature. Employing synthetic gas mixtures comprising carbon dioxide, nitrogen, and argon, the line parameters, including line intensities and self-, N₂- and Ar- broadening coefficients have been retrieved in the 2003r-00001 (<em>r</em> = 1,2,3) bands. This retrieval process was facilitated by a multi-spectral fitting program that utilizes Voigt line profiles. A comparative analysis of our measured line intensities and self-broadening coefficients with those present in established databases, such as HITRAN2020, CDSD296, AMES-2021, and HITEMP2010, has been conducted. The line intensities and self-broadening coefficients for ¹²C¹⁶O₂ deviate by an average of less than 1 % from the values reported in the HITRAN2020 database. The J-dependence of N₂- and Ar- broadening coefficients has been investigated by comparing this work with experimental results and theoretical predictions from other vibrational bands. This research offers important experimental references for the improvement of computational models and the exploration of Venus and Mars.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116359"},"PeriodicalIF":2.5,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653244","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":"Detection of lunar water, hydroxyl ion and their diurnal changes from CHACE-2 orbiter observation","authors":"Swastika Chakraborty ,&nbsp;Barun Raychaudhuri ,&nbsp;Tirtha Pratim Das ,&nbsp;Saurabh Das ,&nbsp;Moumita Roy","doi":"10.1016/j.icarus.2024.116365","DOIUrl":"10.1016/j.icarus.2024.116365","url":null,"abstract":"<div><div>This work reports the spatial and diurnal variations of the number densities of lunar molecular water (H₂O), atomic mass unit (amu) 18 and hydroxyl (OH), amu 17 over low (0° to 30°), middle (31° to 60°) and high (61° to 80°) latitudinal regions of the lunar exosphere during the pre-sunrise, noon, sunset and midnight periods using the mass spectrometric data of CHandra's Atmospheric Composition Explorer-2 (CHACE-2) on board Chandrayaan-2, the second lunar mission developed in India. Both H₂O and OH exhibit, particularly in the low latitude regions, a trend of increasing number density after the sunrise and up to noon, followed by a decrease till sunset. An overall higher density of H₂O is obtained compared to the previous reports. The findings are justified in terms of the polar orbital height of the instrument and the duration of data procurement. The maximum number density for the low, middle and high latitudes reaches 5225 cm⁻³, 5135 cm⁻³ and 3747 cm⁻³, respectively. The corresponding OH abundances are found to be 5079 cm⁻³, 5565 cm⁻³ and 5720 cm⁻³. The diurnal variations of H₂O and OH and their comparisons, similar to those of the present report may provide suitable means for tracing the lunar water cycle. The CHACE-2 observations imply that the influence of magnetotail passage on volatiles like water is to be further quantified in future missions with other sensors.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116365"},"PeriodicalIF":2.5,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142653287","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":"Large impact features on Ganymede and Callisto as revealed by geological mapping and morphometry","authors":"Oliver L. White ,&nbsp;Jeffrey M. Moore ,&nbsp;Paul M. Schenk ,&nbsp;Donald G. Korycansky ,&nbsp;Andrew J. Dombard ,&nbsp;Martina L. Caussi ,&nbsp;Kelsi N. Singer","doi":"10.1016/j.icarus.2024.116357","DOIUrl":"10.1016/j.icarus.2024.116357","url":null,"abstract":"<div><div>The icy Galilean satellites are host to a broad range of impact feature morphologies. Hypotheses seeking to explain the diversity of these impact features consider the effects of impact melt, the physical state of the subsurface at the time of impact, and the impactor characteristics. As part of a larger effort to assess the role of these factors in the formation and evolution of these impact features, we have performed topographic and geological mapping of 19 large impact features on Ganymede and Callisto. These are divided into two main morphological groups: craters (subdivided into pit, dome, and anomalous dome craters), and penepalimpsests/palimpsests. The transitions from pit, dome, to anomalous dome craters appear to be size-dependent up to diameters of ∼170 km. The morphologies of pit and dome craters appear to be independent of their age or geologic context. The impacts that formed them only affected a cold, rigid ice layer, with the development of pits and raised annuli on their floors possibly stemming from the evolution of a pocket of impact melt. The subdued rims and floors of anomalous dome craters indicate the increasing effect of a weak, warm ice layer on impact feature morphology with increasing size, but their prominent annuli and pits indicate that mobilization of impact melt is also a factor. The very low topographic relief of older penepalimpsests and palimpsests indicates that their impacts penetrated the ice shell to mobilize very large volumes of pre-existing liquid from a subsurface layer, with little contribution to the final feature morphology from impact melt. Penepalimpsests are distinguished from palimpsests by the higher frequency of concentric ridges within their interiors, indicating a generally more robust state of the subsurface that could better support the rotation and uplift of solid material during impact, even if a crater-like depression could not be supported. A few impact features seem to be transitional between anomalous dome craters and penepalimpsests, and the overlap of anomalous dome craters, penepalimpsests, and palimpsests in terms of diameter as well as age indicates that impactor size and subsurface properties over time are major factors in determining which of these morphologies emerges.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116357"},"PeriodicalIF":2.5,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578748","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":"Baroclinic waves observed on Mars from InSight data","authors":"Victor Corchete","doi":"10.1016/j.icarus.2024.116361","DOIUrl":"10.1016/j.icarus.2024.116361","url":null,"abstract":"<div><div>Baroclinic waves has been observed in the Martian atmosphere, and their periods have been calculated by means of spectral analysis of the pressure and wind velocity data, provided by the InSight mission for the time periods of the spring and winter seasons. For the spring time, the pressure spectrum shows a peak at the frequency of 0.246 (4 sol). For the winter time, the spectra of the pressure and wind velocity show a dominant peak at the frequency of ∼0.15 (6.7 sol), and a smaller peak at the frequency of ∼0.435 (2.3 sol). The results of this study are consistent with those determined in previous studies from spectral analysis of the Viking 2 data, and it is expected that a further analysis of the results determined in this study will provide a valuable insight into the seasonal changes of the atmospheric structure and circulation, which may be useful to fit General Circulation Models of the Martian atmosphere. However, a general understanding of Martian baroclinic phenomena only will be achieved with a combination of data from multiple Martian midlatitude stations in future missions.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"426 ","pages":"Article 116361"},"PeriodicalIF":2.5,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142560984","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}