Icarus最新文献 - Book学术

Relationships between lobate debris aprons and lineated valley fill on Mars: Evidence for an extensive Amazonian valley glacial landsystem in Mamers Valles 火星上叶状碎屑围岩与线状山谷填充物之间的关系：马默斯谷地广泛的亚马逊河谷冰川地貌系统的证据

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-12 DOI: 10.1016/j.icarus.2024.116373

Lukas Wueller , James W. Head , Erica R. Jawin , Thomas Heyer , Harald Hiesinger , Carolyn H. van der Bogert

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.

我们研究了火星上马默斯谷（Mamers Valles）中线状谷地填充物（Lineated Valley Fill，LVF）和叶状碎屑围岩（Lobate Debris Aprons，LDA）的特征和关系，马默斯谷是位于二分边界的一个长达 950 公里的褶皱谷地。通过详细分析LDA/LVF的形态、地形和相关特征，建立了这些冰川地貌之间的关系和区别，以了解它们的起源和变化。我们记录了无约束 LDA 向压缩和褶皱 LVF 的过渡，反之亦然，这意味着 LDA 和 LVF 在形态和起源方式上密切相关。线性 LDA 在马默斯谷地中占主导地位，源于凹地、类似剧院的残留陨石坑边缘和支流山谷，而环状 LDA 则分布在孤立的山丘周围。狭窄的山谷区域显示出来自两侧的裂片汇聚在一起，形成平行的线性山脊，这些山脊变形为复杂的褶皱，成为低纬度褶皱带，通常沿局部和区域的山谷方向向下流动。与此相反，当低纬度褶皱流出地形封闭的区域时，物质就会形成类似于石灰岩的低纬度褶皱。因此，当地地形是决定矿床是呈现 LVF 型、LDA 型，还是同时具有这两种特征的主要因素。叠加陨石坑形态和探地雷达数据表明，目前地表下的冰层受到 15-20 米升华滞后沉积物的保护，叠加陨石坑形成后的变形和流动极小。根据区域整合得出的解释是，LDA-LVF暴露和冰进入褶皱山谷的点代表了更广泛的区域性亚马逊高原冰川地貌系统的衰退阶段，该系统占据了早在晚努阿契世-早黑斯佩尔世形成的褶皱地形山谷。

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引用次数: 0

How might a planet between Mars and Jupiter influence the inner solar system? effects on orbital motion, obliquity, and eccentricity 火星和木星之间的行星会如何影响内太阳系？对轨道运动、斜度和偏心率的影响

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-07 DOI: 10.1016/j.icarus.2024.116364

Emily Simpson , Howard Chen

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 (

< 3

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

\sim 55 °

, and (iii) perturbed the eccentricity of Venus by up to

e \sim 0.4

. 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.

正如系外行星数量普查所暗示的那样，超地球在银河系中极为常见。在太阳系中，模型表明，如果地球质量到超地球质量的行星能够在早期太阳系其余部分与类木行星世界激烈而混乱的撞击事件中幸存下来，那么这种天体很容易在内部区域（<3 AU）形成。在这项研究中，我们使用一个三维（3D）N-刚体积分器来检验这种假设的后果。在三维模型中，行星被模拟为一个刚体，以考虑其有限的大小和自转，我们模拟了三颗内行星在 2 Myr 周期内的轨道演变。我们的研究结果表明，如果在 2 至 3.5 AU 之间再增加一颗超地球大小的行星，将会：(i) 在 1 至 2 Myrs 的时间尺度内破坏地球轨道的稳定；(ii) 使火星的斜度增加 ∼ 55°；(iii) 使金星的偏心率受到高达 e∼0.4 的扰动。我们的研究探讨了陆地行星的 "另一种命运"，我们的结果表明，内太阳系中超级地球的形成将对陆地行星的轨道动力学和宜居性产生严重后果。

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引用次数: 0

Global characterization of the early-season dust storm of Mars year 36 火星第 36 年早季沙尘暴的全球特征

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-07 DOI: 10.1016/j.icarus.2024.116369

C. Martín-Rubio, A. Vicente-Retortillo, G. Martínez-Esteve, F. Gómez, J.A. Rodríguez-Manfredi

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).

尘暴是火星上最重要的尘土飞扬机制之一，对温度和大气动力学有重大影响。区域性风暴一般发生在南半球的春季和夏季，但也观测到一些在一年中较早的时候发生。虽然多年来对这些早季风暴的研究很少，但它们的出现会产生重要的尘埃扬升。通过对它们的垂直和水平研究，我们可以了解引发它们的沙尘分布机制以及它们发生的地区。在这项研究中，我们比较了 MY 29 和 36 早期风暴的沙尘模式。此外，我们还在每个经度对发生在 MY 36 的早期风暴进行了全球分析，该风暴是在如此早的时间内探测到的最强烈的风暴。我们使用了火星气候探测器（MCS）提供的尘埃和温度测量数据以及火星彩色成像仪（MARCI）提供的图像，这两台仪器都搭载在火星勘测轨道器（MRO）上。

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引用次数: 0

Identification of candidate martian maars in Arena Colles and Nephentes/Amenthes with extension to maars as a proxy for past ground water/ice depths 在阿雷纳科列斯和奈芬特斯/阿门特斯确定候选火星环形山，并将环形山扩展为过去地下水/冰深度的替代物

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-06 DOI: 10.1016/j.icarus.2024.116368

Alison H. Graettinger, Julia Boyd, Joseph A. Nolan

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.

火山口是地下水/冰与上升岩浆之间的地下爆炸相互作用所产生的火山构造的顶部。最近对陆地火山口的全面研究已经确定了复杂的火山口几何形状的共性，这些几何形状由重叠的圆形部分和近乎连续的单一外缘组成。这些独特的几何形状以及火星上高空间分辨率的可见光图像为识别和评估火星上的候选火山口提供了机会。这项研究评估了阿瑞纳科林斯和奈芬特斯/阿门特斯的 49 个闭合凹陷，依据是这些凹陷是否靠近拟火山起源的凹陷锥。在这两个区域中，有 13 个候选火星环形山因其与陆地环形山的相似性而被确认，这些环形山没有任何与其他形成过程（如二元环形山周围的蝶形喷出物）有关的排他性特征。识别火星上的火山口将为火山爆发时地下水和冰的存在和深度范围提供额外的代用指标。火星环形山中多个重叠的圆形部分的直径可用来提供底层二迭熔岩深度的一阶估计值，作为爆炸深度的代用指标，从而确定地下是否有水。根据此处确认的 13 个候选火山口的圆形部分进行的估算表明，火山形成时的水/冰深度在 0.6 至 4 千米之间。

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引用次数: 0

3D morphometry of Martian craters from HRSC DEMs using a multi-scale semantic segmentation network and morphological analysis 利用多尺度语义分割网络和形态学分析，从 HRSC DEMs 得出火星陨石坑的三维形态测量结果

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-04 DOI: 10.1016/j.icarus.2024.116358

Peiqi Ye , Rong Huang , Yusheng Xu , Wendi Li , Zhen Ye , Xiaohua Tong

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.

撞击坑的形态揭示了火星表面的结构和组成，特别是地下条件和火星地质历史，在火星探测任务中具有越来越重要的意义。本研究提出了一种用于探测和划分火星撞击坑的三维形态测量方法，并进行了三维形态分析。具体来说，这项工作首先侧重于火星陨石坑的分割。然后根据分割结果对陨石坑实例进行聚类。最后，对提取出的单个陨石坑进行形态分析，包括测量其直径、深度、面积、均方根高度、边缘高度、圆度及其统计数据。与以往主要使用光学图像和物体检测方法的研究不同，这项工作将陨石坑提取视为语义分割任务，而不是物体检测任务，以便更好地划分精确的形状和边界信息。利用数字高程模型（DEM）作为原始数据，直接获取三维信息，并将其转换为三维点云格式，输入多尺度语义分割网络。在测试数据上，语义分割结果的总体准确率达到 0.932，mIOU 达到 0.871。我们自动统计了 Noachis Terra 的 63 个陨石坑和 Terra Cimmeria 的 40 个陨石坑。三维形态测量结果显示，第一个地区 66% 的撞击坑直径大于 10 千米，而第二个地区 50% 的撞击坑直径大于 10 千米。利用所提出的方法，我们可以自动对火星陨石坑进行三维形态测量，其效率比人工陨石坑分析工具提高了 15 倍。所获得的三维形态测量结果可为今后的火星地貌研究提供参考和支持。

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引用次数: 0

Maximum dust-to-gas mass flux ratio in spherically expanding dusty-gas flow 球形膨胀尘气流中尘埃与气体的最大质量通量比

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-03 DOI: 10.1016/j.icarus.2024.116363

V.V. Zakharov , N.Y. Bykov , A. Rotundi , A.V. Rodionov , V. Della Corte , S.L. Ivanovski

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).

在本文中，我们把固体球形粒子在球形膨胀气体流中的运动视为彗星气尘大气的基本模型。根据数值模拟的结果，我们提出了尘埃末端速度的近似值，并估算了尘埃与气体的最大质量通量比（在尘埃大小分布由幂律给出的尘埃-气体流中），该近似值与尘埃对气体流的影响可忽略不计的假设（常用于模拟尘埃气体流）是一致的。

引用次数: 0

Measurements of line parameters for 12C16O2 near λ = 1.05 μm by cavity ring-down spectrometer 利用空腔环降光谱仪测量 λ = 1.05 μm 附近 12C16O2 的线参数

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-11-02 DOI: 10.1016/j.icarus.2024.116359

Tao Yang , Xianmei Qian , Qiang Liu , Wenyue Zhu , Hongliang Ma , Jianjie Zheng , Chaolong Cui , Xiaomei Jin , Jun Huang

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 (r = 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.

利用连续波腔环降光谱仪在室温下精确测量了 12C16O2 在 9358-9648 cm-1 波长范围内的吸收光谱。利用由二氧化碳、氮气和氩气组成的合成气体混合物，对 2003r-00001 (r = 1,2,3) 波段中的线参数进行了检索，包括线强度和自、N2- 和氩气展宽系数。利用 Voigt 线剖面的多光谱拟合程序为这一检索过程提供了便利。我们将测得的线强度和自宽系数与现有数据库（如 HITRAN2020、CDSD296、AMES-2021 和 HITEMP2010）中的线强度和自宽系数进行了比较分析。12C16O2 的线强度和自展宽系数与 HITRAN2020 数据库中报告的数值平均偏差不到 1%。通过与实验结果和其他振动波段的理论预测进行比较，研究了 N2-和 Ar-展宽系数的 J 依赖性。这项研究为改进计算模型以及探索金星和火星提供了重要的实验参考。

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引用次数: 0

Detection of lunar water, hydroxyl ion and their diurnal changes from CHACE-2 orbiter observation 从CHACE-2轨道器观测中探测月球水、羟基离子及其昼夜变化

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-10-31 DOI: 10.1016/j.icarus.2024.116365

Swastika Chakraborty , Barun Raychaudhuri , Tirtha Pratim Das , Saurabh Das , Moumita Roy

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.

这项工作报告了月球外大气层低纬度（0°至 30°）、中纬度（31°至 60°）和高纬度（61°至 80°）区域在日出前、正午、日落和午夜期间月球分子水（H2O）原子质量单位（amu）18 和羟基（OH）原子质量单位（amu）17 的数量密度的空间和昼夜变化、利用印度开发的第二个月球任务 Chandrayaan-2 号上的 CHandra's Atmospheric Composition Explorer-2 (CHACE-2) 的质谱数据，对日出前、正午、日落和午夜期间的月球外大气层进行了分析。特别是在低纬度地区，H2O 和 OH 的数量密度在日出后至正午前呈上升趋势，随后下降，直至日落。与以前的报告相比，H2O 的密度总体较高。从仪器的极轨道高度和数据采集的持续时间来看，这些发现都是合理的。低纬度、中纬度和高纬度的最大数量密度分别达到 5225 cm-3、5135 cm-3 和 3747 cm-3。相应的 OH 丰度分别为 5079 cm-3、5565 cm-3 和 5720 cm-3。与本报告类似，H2O 和 OH 的昼夜变化及其比较可为追踪月球水循环提供合适的方法。CHACE-2 的观测结果表明，磁尾通过对水等挥发物的影响需要在今后的飞行任务中利用其他传感器进一步量化。

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引用次数: 0

Large impact features on Ganymede and Callisto as revealed by geological mapping and morphometry 地质测绘和形态测量揭示的木卫三和卡利斯托大型撞击特征

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-10-30 DOI: 10.1016/j.icarus.2024.116357

Oliver L. White , Jeffrey M. Moore , Paul M. Schenk , Donald G. Korycansky , Andrew J. Dombard , Martina L. Caussi , Kelsi N. Singer

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.

冰冷的伽利略卫星上有各种各样的撞击特征形态。试图解释这些撞击特征多样性的假设考虑了撞击熔体的影响、撞击时地下的物理状态以及撞击者的特征。为了评估这些因素在这些撞击地貌的形成和演变过程中所起的作用，我们对木卫三和卡利斯托上的19个大型撞击地貌进行了地形和地质测绘。这些地貌分为两大形态组：陨石坑（细分为坑状、穹状和异常穹状陨石坑）和半椭球体/椭球体。从凹坑、圆顶到异常圆顶陨石坑的过渡似乎与直径在170千米以下的陨石坑的大小有关。坑状和穹状陨石坑的形态似乎与它们的年龄或地质背景无关。形成这些陨石坑的撞击只影响到冰冷坚硬的冰层，陨石坑底部凹坑和凸起的环状结构可能是由撞击熔融物形成的。异常穹隆陨石坑的边缘和坑底较低，这表明随着体积的增大，弱温冰层对撞击地貌形态的影响越来越大，但其突出的环状凹坑表明撞击熔融物的移动也是一个因素。较早的半侏罗纪火山口和重侏罗纪火山口的地形起伏很低，这表明它们的撞击穿透了冰壳，从地表层下动员了大量原有的液体，而撞击融化物对最终地貌形态的影响很小。半坍方地貌与重坍方地貌的区别在于其内部同心脊的出现频率较高，这表明次表层一般较为坚固，能够更好地支持固体物质在撞击过程中的旋转和隆起，即使无法支持类似陨石坑的凹陷。一些撞击特征似乎是异常穹隆陨石坑和半侏罗纪陨石坑之间的过渡，异常穹隆陨石坑、半侏罗纪陨石坑和垛状陨石坑在直径和年龄上的重叠表明，撞击物的大小和随时间变化的次表层性质是决定这些形态中哪一种出现的主要因素。

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引用次数: 0

Baroclinic waves observed on Mars from InSight data 根据 InSight 数据在火星上观测到的巴洛克波

IF 2.5 2区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Icarus

Pub Date : 2024-10-29 DOI: 10.1016/j.icarus.2024.116361

Victor Corchete

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.

在火星大气中观测到了巴罗克林波，并通过对 InSight 飞行任务提供的春季和冬季压力和风速数据进行频谱分析，计算出了它们的周期。在春季，压力频谱显示出频率为 0.246（4 索尔）的峰值。在冬季，压力和风速频谱在频率 ∼0.15 （6.7 个太阳）处显示出一个主峰，在频率 ∼0.435 （2.3 个太阳）处显示出一个较小的峰值。本研究的结果与以往研究中通过对海盗 2 号数据进行光谱分析而确定的结果相一致，预计对本研究确定的结果进行进一步分析将对大气结构和环流的季节性变化提供有价值的见解，这可能有助于拟合火星大气的一般环流模型。不过，只有在今后的飞行任务中结合多个火星中纬度站的数据，才能对火星的气压现象有一个总体的了解。

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