Icarus最新文献

{"title":"Viewing lobate patterns on Mars and Earth as climate modulated fluid-like instabilities","authors":"JohnPaul Sleiman ,&nbsp;Susan J. Conway ,&nbsp;Andreas Johnsson ,&nbsp;James Wray ,&nbsp;Rachel Glade","doi":"10.1016/j.icarus.2025.116580","DOIUrl":"10.1016/j.icarus.2025.116580","url":null,"abstract":"<div><div>Lobate features found on high-latitude slopes on Mars resemble terrestrial cold-climate soil patterns known as solifluction lobes. Whether this provides evidence of freeze thaw processes on Mars or pattern equifinality is up for debate. Guided by recently developed theory for solifluction pattern formation inspired by fluid instabilities, here we compare HiRISE imagery of Martian lobes with a large dataset of solifluction lobes on Earth and find that they exhibit similar morphologic scaling. Our data show that Martian lobes are roughly 2.6 times taller than their Earth counterparts, indicative of lobe height set by cohesive soil strength under different gravitational conditions. We also explore possible climate controls on Martian lobe morphology using elevation, aspect, and temperature data. Our work suggests mechanistic similarities between lobate patterns on Earth and Mars that point toward icy origins for these features, with implications for our understanding of climate controls on Martian surface processes.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116580"},"PeriodicalIF":2.5,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739123","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":"Understanding compositional evolution of hollows at Dominici crater, Mercury","authors":"A. Emran,&nbsp;K.M. Stack","doi":"10.1016/j.icarus.2025.116576","DOIUrl":"10.1016/j.icarus.2025.116576","url":null,"abstract":"<div><div>Hollows on Mercury are small depressions formed by volatile loss, providing important clues about the volatile inventory of the planet's surface and shallow subsurface. We investigate the composition of hollows in various phases of devolatilization at Dominici crater. By applying a machine learning approach to MESSENGER Mercury Dual Imaging System data, we defined surface units within the study area and extracted their reflectance spectra. We applied linear (areal) spectral modeling using laboratory sulfides, chlorides, graphite, and silicate mineral spectra to estimate the composition of hollows and their surrounding terrains. At Dominici, the hollow on the crater rim/wall is interpreted to be active, while that in the center of the crater is interpreted as a waning hollow. We find that the active hollow predominantly comprises silicates (augite and albite), with a trace amount of graphite and CaS. In contrast, waning hollows contain marginally elevated sulfides (MgS and CaS) and graphite, but slightly lower silicates than the active hollow. The spectra of low reflectance terrain surrounding the hollows appear to be dominated by graphite and sulfides, which contribute to its darker appearance. We suggest that hollow at the crater forms due to thermal decomposition of sulfides, primarily MgS possibly mixed with CaS, as well as possible the depletion of graphite. As devolatilization wanes, a mixture of predominantly silicate minerals remains in the hollows — impeding further vertical growth.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116576"},"PeriodicalIF":2.5,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739124","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":"Outgassing of ice agglomerates II","authors":"Konrad J. Kossacki","doi":"10.1016/j.icarus.2025.116541","DOIUrl":"10.1016/j.icarus.2025.116541","url":null,"abstract":"<div><div>The aim of the work is to analyze limitations of the applicability of equations for the rate of outgassing of the nuclei of comets. I presented the results of experiments performed using large samples composed of agglomerates of radii up to few centimeters. In this respect the present work is the continuation of the paper Kossacki et al. (2023) about the outgassing of mixtures of millimeter sized agglomerates. The ratio between the radii of agglomerates and the radii of smallest grains present in agglomerates was previously about 10 and now is about 100. The measured changes of masses of the samples during experiments were compared with the results of calculations based on the structures of the samples and the recorded temperatures. Considered were two different mathematical models. One requires knowledge of the porosity, but not of the granulation of material (Kossacki 2021), while the second assumes knowledge of the radii of the smallest grains and of the agglomerates, as well as of the vapor pressure in pores between agglomerates (Kossacki et al. 2023). It was found that: (1) both models can reproduce the results of experiments and (2) the gas pressure in pores normalized to the pressure of phase equilibrium exhibits strong dependence on the temperature and weak dependence on the sizes of agglomerates. Based on the presented results I recommend to use equations which do not include the vapor pressure in pores.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116541"},"PeriodicalIF":2.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734992","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":"Hypervelocity impact experiments in iron alloy targets","authors":"Yangyu Lu ,&nbsp;Meng-Hua Zhu ,&nbsp;Qiang Wu ,&nbsp;Siyuan Ren","doi":"10.1016/j.icarus.2025.116575","DOIUrl":"10.1016/j.icarus.2025.116575","url":null,"abstract":"<div><div>In this work, we conducted hypervelocity impact experiments on iron alloy targets (FeNi36 and stainless steel SS304) at various impact angles using a two-stage light-gas gun. Our investigation focuses on the structure of impact craters formed on metallic targets, with implications for understanding potential crater formation on metal asteroids, such as those on Psyche. Our results show distinct differences in the crater morphologies of FeNi36 and SS304 targets, particularly in terms of crater size and rim features, which can be attributed to variations in material properties such as hardness and strength. We derived empirical equations from both our current experiments and previous studies with a wide range of iron alloy targets to estimate crater diameter and depth. The experimental results from our oblique impacts on iron alloy targets demonstrate that the variation in crater dimensions (i.e., depth, length, and diameter) primarily follow a <em>sinθ</em> relationship with respect to the impact angle. For metallic targets at oblique impacts, the material properties of both the projectile and target exert a significant influence on crater morphology, particularly at low impact angles, where they notably affect crater length. These findings may provide additional understanding of crater formation process on metal asteroids, such as those on the Psyche asteroid.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116575"},"PeriodicalIF":2.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748327","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":"The role of pre-existing topography in modulating lunar lava flow widths, depths and channel structure","authors":"Yuan Chen ,&nbsp;James W. Head ,&nbsp;Lionel Wilson ,&nbsp;Mikhail A. Kreslavsky ,&nbsp;Edward Davis ,&nbsp;Xingguo Zeng ,&nbsp;Xin Ren ,&nbsp;Jianjun Liu ,&nbsp;Chunlai Li","doi":"10.1016/j.icarus.2025.116564","DOIUrl":"10.1016/j.icarus.2025.116564","url":null,"abstract":"<div><div>Lunar volcanism is one of the most important endogenic processes on the Moon. The final morphology of a lava flow depends on (a) the composition of the magma, which determines its rheology, (b) the effusion rate, controlled by the geometry of the dike transferring the magma to the surface and the overpressure in the magma source, (c) the lava cooling behavior influenced by whether the flow is laminar or turbulent, (d) the total volume of magma erupted, and the topography of the surface onto which the lava flows. Thus, studying the morphology of flows sheds light on their eruption conditions, and has implications for the nature of the magma source region. In this study, we document the effects of topography on a well-preserved Eratosthenian-aged lava flow that most likely originated from the volcanic complex around Euler Crater in Mare Imbrium. We assess how the observations can improve our understanding of previous models of lunar lava flow emplacement and cooling behavior. We find that: 1) the pre-existing topography significantly affected the morphology of the flow; 2) several low wrinkle ridges predating the eruption and controlling the flow path underwent significant tectonic modification after lava emplacement; 3) variations in the extent of lava channel/levee structures along the flow are linked to turbulent/laminar flow modes; 4) the emplacement of the lava flow investigated here was probably completed in about a week, occurring in the very early period of regional wrinkle ridge formation. This lava flow history provides new insight into the interplay of regional volcanism and tectonism in Mare Imbrium and late-stage lunar thermal evolution in general.</div></div><div><h3>Key points</h3><div><ul><li><span>•</span><span><div>The geometric and morphological features of lava flows can be significantly affected by pre-existing topography.</div></span></li><li><span>•</span><span><div>The observed channel within a well-preserved Imbrium lava flow is interpreted to imply a transformation of flow mode from turbulent to laminar.</div></span></li><li><span>•</span><span><div>We deduced the paleo-geological sequence of processes forming this Imbrium lava flow.</div></span></li></ul></div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116564"},"PeriodicalIF":2.5,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734993","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":"Surface activity of H2O and CO2 on comet 103P/Hartley2 derived from EPOXI/HRI images","authors":"Yinsi Shou ,&nbsp;Michael Combi ,&nbsp;Lori Feaga ,&nbsp;Valeriy Tenishev ,&nbsp;Tony Farnham ,&nbsp;Nicolas Fougere","doi":"10.1016/j.icarus.2025.116557","DOIUrl":"10.1016/j.icarus.2025.116557","url":null,"abstract":"<div><div>On November 4, 2010, the EPOXI extended the mission of the Deep Impact spacecraft, flew by comet 103P/Hartley 2, and made a series of spectral images in both the infrared and the visible. The High-Resolution Instrument Infrared Spectrometer (HRI-IR) observed the comet and its surrounding coma, enabling maps in the light of the infrared emissions of H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O at <span><math><mrow><mn>2</mn><mo>.</mo><mn>7</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> and CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> at <span><math><mrow><mn>4</mn><mo>.</mo><mn>3</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> to be made. We have extended an inversion method originally developed to map out potential activity on the surface of comet 67P/Churyumov–Gerasimenko from ROSINA mass spectrometer measurements as part of the Rosetta mission to enable making similar nucleus surface activity maps from 2-D images of H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O and CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> in the inner coma of Hartley 2. Processed close-up column density images show the existence of extended sources for H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O and CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>. Column density profiles specific to an icy grain extended source are derived based on a simple Monte Carlo grain model, and are used to remove the effects of an extended source from a set of 11 spectral maps of each species taken within 1 h of closest approach. We apply the inversion technique to the processed HRI-IR spectral images to calculate the distribution of potential surface activity of both species over the whole surface. Comparisons are made between the processed images, fitted images from the inversion model, and synthetic images generated by the Direct Simulation Monte Carlo (DSMC) coma model, demonstrating that the derived surface activity distributions can reproduce most patterns in the observed images. Production rates from direct nucleus sublimation during the closet approach period are characterized based on the DSMC model results.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116557"},"PeriodicalIF":2.5,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724695","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":"Magnetic topology dependence of ionizing electrons on the Martian nightside ionosphere","authors":"Arnob Sarkar ,&nbsp;N.V. Rao ,&nbsp;Pavan D. Gramapurohit ,&nbsp;Umesh R. Kadhane","doi":"10.1016/j.icarus.2025.116566","DOIUrl":"10.1016/j.icarus.2025.116566","url":null,"abstract":"<div><div>The interaction between the solar wind and Martian crustal magnetic fields plays a significant role in shaping electron precipitation in the ionosphere, particularly on the nightside. Using five years of data from the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, this study explores how magnetic topology influences the distribution of ionizing electrons, quantified through the electron impact ionization frequency (EIIF). Data from MAVEN's Solar Wind Electron Analyzer (SWEA) and magnetometer (MAG) were analyzed, with strong and weak crustal field regions defined at observation altitudes using a crustal field model. As expected, the results demonstrate that magnetic topology critically influences the altitude distribution of EIIF on the nightside. However, variations in EIIF across the terminator reveal dynamic and novel patterns. In open and draped topologies, EIIF decreases gradually from the dayside, across the terminator, and onto the nightside. Conversely, closed topologies exhibit a sharper decrease in EIIF across the terminator, characterized by strong altitude dependence. This is attributed to day-to-night transport along cross-terminator closed field lines. Below 600 km on the nightside, EIIF in closed topologies is up to two orders of magnitude lower than in open and draped topologies due to the shielding effect of crustal fields, with stronger shielding observed at lower altitudes. Above 240 km, EIIF in open and draped topologies shows no dependence on crustal field strength and weak dependence on solar wind dynamic pressure (P_sw). In contrast, the EIIF in closed topologies shows a strong dependence on magnetic field strength and a weak dependence on P_sw. These findings provide critical insights into the role of magnetic topology in electron precipitation, aiding the parameterization of electron dynamics in global circulation models of the Martian ionosphere.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116566"},"PeriodicalIF":2.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697851","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":"The role of planetary-scale waves on the stratospheric superrotation in Titan's atmosphere","authors":"Yuan Lian ,&nbsp;Cecilia Leung ,&nbsp;Claire Newman ,&nbsp;Leslie Tamppari","doi":"10.1016/j.icarus.2025.116561","DOIUrl":"10.1016/j.icarus.2025.116561","url":null,"abstract":"<div><div>We analyze simulation results from the TitanWRF global circulation model to understand the mechanisms that maintain the equatorial superrotation in Titan's stratosphere. We find that the eddies associated with wave activities can transport angular momentum upgradient to zonal flow, leading to acceleration of the equatorial superrotation. The dominant wave modes identified in this study are consistent with previous studies, with zonal wavenumber 1 being the major contributor to the prograde acceleration. Despite the same conclusion of maintenance of equatorial superrotation <em>via</em> wave-mean interactions, we find that the way waves interact with the zonal flow in TitanWRF is slightly different from some other studies. We confirm our previous findings that in TitanWRF this occurs primarily during a dozen or so annual, short-duration (a few Titan sols) angular momentum “transfer events,” which have a repeatable seasonal pattern but differ slightly in timing and magnitude between years. This is not the case in the Titan Atmosphere Model (TAM), which found milder angular momentum transfers that produced the strongest acceleration of superrotation around solstice in the upper stratosphere and more continuous year-around acceleration in the lower stratosphere. Despite differences in angular momentum transfer across models, we further find that, similar to the TAM wave analysis results, eddies generated by Rossby-Kelvin instabilities may be the major source of prograde angular momentum for the equatorial superrotation, although TitanWRF may also include contributions from the absorption of vertically propagating equatorial Kelvin waves. This differs from our previous work, which suggested barotropic waves were responsible for TitanWRF's solsticial transfer event.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116561"},"PeriodicalIF":2.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706120","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":"Characterization of lobate scarps at the western rim of the Apollo basin using high-resolution DEMs generated using generative adversarial network (GAN) based approach","authors":"Xijian Li ,&nbsp;Zongyu Yue ,&nbsp;Man Peng ,&nbsp;Kaichang Di ,&nbsp;Biao Wang ,&nbsp;Yexin Wang ,&nbsp;Gregory Michael ,&nbsp;Congzhe Wu ,&nbsp;Jianzhong Liu","doi":"10.1016/j.icarus.2025.116562","DOIUrl":"10.1016/j.icarus.2025.116562","url":null,"abstract":"<div><div>Chang'e-6 is the first sample-return mission from the lunar farside and has returned samples from the landing site within the Apollo basin on June 25, 2024. Lobate scarps have been identified approximately 300 km northwest of the Chang'e-6 landing site (and at western rim of the Apollo basin). The distribution and morphological characteristics of lobate scarps are crucial for understanding the lunar geological history of the landing area. In this research, we have analyzed the spatial distribution and formation age of lobate scarps at western rim of the Apollo basin. The morphology, dynamical models, and formation ages of lobate scarps are investigated through Mohr-Coulomb measurement and crater size-frequency distribution measurements (CSFD). We generated high-resolution digital elevation models by deep learning method using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) imagery and Selenological and Engineering Explorer (SELENE) and Lunar Orbiter Laser Altimeter (LOLA) Digital Elevation Model (SLDEM), which enabled the study of lobate scarps in areas lacking NAC DTM coverage, and their accuracy were thoroughly validated. The displacement-length ratios of the lobate scarps are calculated, with an average of approximately 3.80 %. By calculating the morphological parameters of lobate scarps, inferring their formation ages, and studying their spatial distribution, we find that these lobate scarps are distributed in the highlands nearby the Apollo basin edge. They were formed under horizontal compressive stresses exceeding 400 MPa during the last 80 Ma, which is consistent with the initially totally molten (ITM) model. This finding is further supported by cross-validation with the ²³⁸U/²⁰⁴Pb ratios from lunar far-side samples by the Chang'e-6 mission, challenging the notion that the lunar magma ocean (LMO) can prolong magmatic activity through KREEP.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116562"},"PeriodicalIF":2.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697850","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":"Exobase and homopause altitudes in the Martian upper atmosphere: Solar cycle variability and response to the 2018 global dust storm","authors":"N.V. Rao ,&nbsp;V. Leelavathi ,&nbsp;Neha Gupta","doi":"10.1016/j.icarus.2025.116565","DOIUrl":"10.1016/j.icarus.2025.116565","url":null,"abstract":"<div><div>Understanding the composition of volatile gases in the Martian upper atmosphere and the mechanisms governing their escape into outer space is crucial for unraveling planetary evolution. Two critical neutral atmospheric boundaries, the exobase and the homopause, play key roles in this context. In this study, we conducted a detailed analysis of the exobase and homopause altitudes derived from measurements by the Neutral Gas and Ion Mass Spectrometer (NGIMS) aboard the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. The exobase and homopause altitudes observed in this study range from 140 to 200 km and 90–135 km, respectively, broadly agreeing with values reported in previous studies. Using extended observations, this study reveals significant interannual variability in these altitudes. Both the exobase and homopause were found to be higher during moderate solar activity compared to solar minimum. During moderate solar activity, these two altitudes rise and fall nearly synchronously, while this coupling weakens during solar minimum. Seasonal trends are also pronounced, with elevated altitudes observed during perihelion and in the summer hemisphere, particularly during the southern summer. These findings suggest that enhanced solar activity during moderate solar periods increases atmospheric heating, elevating atmospheric scale heights and causing the exobase and homopause to rise and fall in-phase. In contrast, during solar minimum, weaker thermal forcing reduces the influence of atmospheric expansion, allowing gravity wave activity to dominate the variability of the homopause. During the 2018 global dust storm (GDS), exobase altitudes were elevated with reduced sinusoidal amplitude, while homopause altitudes exhibited significant fluctuations. These results indicate that thermospheric expansion raises the altitudes of both boundaries during the GDS, but enhanced gravity wave activity introduces substantial fluctuations in the homopause altitude, disrupting its coupling with the exobase and resulting in a phase shift between the variations of these two critical altitudes.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"435 ","pages":"Article 116565"},"PeriodicalIF":2.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697852","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}