Icarus最新文献

{"title":"Unlocking planetesimal magnetic field histories: A refined, versatile model for thermal evolution and dynamo generation","authors":"Hannah R. Sanderson ,&nbsp;James F.J. Bryson ,&nbsp;Claire I.O. Nichols ,&nbsp;Christopher J. Davies","doi":"10.1016/j.icarus.2024.116323","DOIUrl":"10.1016/j.icarus.2024.116323","url":null,"abstract":"<div><div>The thermal and magnetic histories of planetesimals provide unique insights into the formation and evolution of Earth’s building blocks. These histories can be gleaned from meteorites by using numerical models to translate measured properties into planetesimal behaviour. In this paper, we present a new 1D planetesimal thermal evolution and dynamo generation model. This magnetic field generation model is the first of a differentiated, mantled planetesimal that includes both mantle convection and sub-eutectic core solidification. We have improved fundamental aspects of mantle heat transport by including a more detailed viscosity model and stagnant lid convection parametrisations consistent with internal heating. We have also added radiogenic heating from ⁶⁰Fe in the metallic Fe-FeS core. Additionally, we implement a combined thermal and compositional buoyancy flux, as well as the latest magnetic field scaling laws to predict magnetic field strengths during the planetesimal’s thermal evolution until core solidification is complete. We illustrate the consequences of our model changes with an example run for a 500<!--> <!-->km radius planetesimal. These effects include more rapid erosion of core thermal stratification and longer duration of mantle convection compared to previous studies. The additional buoyancy from core solidification has a marginal effect on dynamo strength, but for some initial core sulfur contents it can prevent cessation of the dynamo when mantle convection ends. Our model can be used to investigate the effects of individual parameters on dynamo generation and constrain properties of specific meteorite parent bodies. Combined, these updates mean this model can predict the most reliable and complete magnetic field history for a planetesimal to date, so is a valuable tool for deciphering planetesimal behaviour from meteorite properties.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116323"},"PeriodicalIF":2.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356766","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":"Low temperature phase transitions in the visible and near-infrared (VNIR) reflectance spectra of (NH4)2HPO4 and (NH4)HSO4 salts","authors":"M. Fastelli ,&nbsp;B. Schmitt ,&nbsp;P. Beck ,&nbsp;O. Poch ,&nbsp;A. Zucchini ,&nbsp;P. Comodi","doi":"10.1016/j.icarus.2024.116321","DOIUrl":"10.1016/j.icarus.2024.116321","url":null,"abstract":"<div><div>The detection of ammonium bearing crystalline solids in salt-water systems on icy bodies and solar system bodies could provide information about the ascent of these salts from a deep reservoir within the hydrosphere. Due to their chemical-physical properties, NH₄⁺ compounds play a key role both in the internal dynamics of celestial bodies and in the potential habitability of ocean worlds. In this work we analysed the reflectance spectra of two synthetic NH₄⁺ salts: ammonium hydrogen phosphate (NH₄)₂HPO₄ and ammonium hydrogen sulphate (NH₄)HSO₄ in the 1–4.2 μm spectral range at low temperature, between 110 and 290 K. For (NH₄)₂HPO₄ we also examined the effect of three different grain sizes (150–125 μm; 125–80 μm; 80–32 μm). The collected reflectance spectra show absorption features related to NH₄⁺ group overtone and combination modes in the 1–2.5 μm range. In particular, the bands located at ∼1.09 μm (3ν₃), ∼1.30 μm (2ν₃ + ν₄), ∼1.58 μm (2ν₃), ∼2.02 μm (ν₂ + v₃) and ∼ 2.2 μm (<em>v</em>₃ + v₄) could be useful to discriminate these salts. The low temperature spectra, compared to those at ambient temperature, reveal finer structures, displaying sharper and narrower absorption bands. The selected NH₄⁺-bearing salts are subjected to reversible low temperature phase transitions, which are revealed in the spectra by a progressive growth and shift of the bands toward shorter wavelengths with a drastic change of their depth. We performed laboratory measurements of ammonium (NH₄⁺) compounds to address the limited data available expanding the existing database. The collected cryogenic spectra can be directly compared with remote sensing data from planetary missions of the upcoming decade such as NASA's Europa Clipper, and ESA's JUICE and the newly launched James Webb Space Telescope expanding the existing database of ammonium compounds at cryogenic temperature.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116321"},"PeriodicalIF":2.5,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326803","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":"Refined 70-cm earth-based lunar radar maps and a new interpretation of the Cruger-Sirsalis cryptomare","authors":"Bruce A. Campbell ,&nbsp;Erica R. Jawin ,&nbsp;Gareth A. Morgan","doi":"10.1016/j.icarus.2024.116324","DOIUrl":"10.1016/j.icarus.2024.116324","url":null,"abstract":"<div><div>We present a new processing approach for Earth-based, 70-cm wavelength, dual-polarization radar data collected using the Arecibo and Green Bank Telescopes. Earth-based data represent the only view of the Moon at this wavelength. This methodology greatly improves the synthetic aperture focusing of the images to their best possible spatial resolution, with a concurrent improvement in signal-to-noise ratio and multi-look summing. Image coverage is also expanded to the full illuminated beam area. Registration to a visible image basemap reduces RMS geographic placement errors to less than ∼2 km. Images collected after the first Planetary Data System archive delivery are also included. Analysis of the circular polarization ratio (CPR) suggests an uncertainty of ∼20 %, based on the likely ∼1 dB error in estimating the background noise in a radar look. We use the new 70-cm maps with topography and 12.6-cm radar images to revisit an initial study of cryptomare units in the Cruger-Sirsalis region, and find that mare contamination of the Orientale ejecta must be well-mixed with highland material, as opposed to the earlier hypothesis of a highland-dominated blanket over mare-rich regolith. This result shows that the two radar wavelengths provide a more complete view of the cryptomare regolith cross section, and that radar signatures can delineate ilmenite contamination of highlands areas where multi-spectral methods are limited by other factors.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116324"},"PeriodicalIF":2.5,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356762","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":"Morphometry and kinematics correlation of wrinkle ridges on Mars: Insights from Trishear modelling","authors":"F. Carboni,&nbsp;O. Karagoz,&nbsp;T. Kenkmann","doi":"10.1016/j.icarus.2024.116330","DOIUrl":"10.1016/j.icarus.2024.116330","url":null,"abstract":"<div><div>Wrinkle ridges are among the most common and controversial compressional tectonic structures on terrestrial planets. While their origins are well inferred to be related to crustal shortening driven by compressional stress, their subsurface characterization is still a matter of debate. Open questions remain about the geometry, number, structural style and kinematics of faults promoting wrinkle ridges. We use the Trishear and Fault-Parallel-Flow integrated forward kinematic modelling to model wrinkle ridges related faults. This is achieved through a series of balanced cross sections and a consequent set of narrow 3D models. We perform a detail kinematic analysis on nine wrinkle ridges: six are located in the circum-Tharsis regions of Lunae Planum and Solis Planum, while three are located in the Hellas Planitia, Hesperia Planum and Syrtis Major Planum, respectively. The applied methodology allows us to quantitatively assess wrinkle ridges geometry and kinematics, and to correlate them with morphometric parameters (i.e., width and relief). Our results indicate how wrinkle ridges tectonics can be characterized by a more complex array of faults than previously modelled. This leads to a total amount of horizontal shortening accommodated differently depending on the number and type of faults (i.e., main fault, backthrust, synthetic faults). The location and geometry of the modelled faults suggest the presence of multiple detachments at different depths and with different mechanical behaviors such as weaker and more frictional décollements, which are likely found within sedimentary interlayers. The amount of shortening, the fault geometry and spacing, as well as the upper faults tips depth are positively correlated with major morphometric parameters of wrinkle ridges topography.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116330"},"PeriodicalIF":2.5,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323118","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":"Chandrayaan-3 landing site evolution by South Pole-Aitken basin and other impact craters","authors":"S. Vijayan ,&nbsp;K.B. Kimi ,&nbsp;Anil Chavan ,&nbsp;R. Aditi ,&nbsp;U. Thahira ,&nbsp;V. Rama Subramanian ,&nbsp;Rishitosh K. Sinha ,&nbsp;Amitabh ,&nbsp;Santosh Vadawale ,&nbsp;M. Shanmugam ,&nbsp;N.P.S. Mithun ,&nbsp;Arpit R. Patel ,&nbsp;Amit Basu Sarbadhikari ,&nbsp;K.V. Iyer ,&nbsp;K. Suresh ,&nbsp;Ajay Prashar ,&nbsp;G. Rima ,&nbsp;Anil Bhardwaj","doi":"10.1016/j.icarus.2024.116329","DOIUrl":"10.1016/j.icarus.2024.116329","url":null,"abstract":"<div><div>The Chandrayaan-3 mission with the Vikram-lander and the Pragyan rover landed in the high latitude highland region near the south pole of the Moon. The landing site is located ∼350 km from the South Pole-Aitken basin rim, an ancient and highly cratered terrain. This site has undergone the complex emplacement sequence of SPA basin ejecta followed by the nearby and distant impact basins and crater ejecta materials. To evaluate the source of individual basin and crater ejecta emplacement over this landing site, we carefully demarcated the nearby and distal basins and craters that could have contributed to the source regolith material. We found that the SPA basin is the major contributor, which deposited nearly ∼1400 m of ejecta materials, and 11 other basins deposited ∼580 m of ejecta. The other complex craters contributed up to ∼90 m of ejecta. Meanwhile, secondary craters of a few km in diameter located adjacent to the landing site contributed to ∼0.5 m ejecta, which are crucial target materials for the Pragyan rover insitu analysis. Pragyan rover images revealed the landing site is devoid of &gt;1 m boulders along the traverse revealing typical highland terrain. The Pragyan rover Navcam and Orbital High Resolution Camera regional images revealed linear distal ejecta rays possibly from the distant impacts as insitu evidence of foreign material at the CH-3 landing site. We found a semi-circular, heavily degraded structure encompassed around the landing site, which is interpreted as a buried impact crater ∼160 km in diameter probably formed before the SPA basin. The erasure of pre-SPA basin craters is caused by both the direct burial by SPA basin ejecta, high seismic shaking during SPA formation, and then followed by various post-SPA craters and its associated some of the degradation processes. Overall, Chandrayaan-3 landed within an ancient region that hosts some of the most deeply excavated materials on the Moon.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116329"},"PeriodicalIF":2.5,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323117","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":"Survey of remnant seasonal ice patches at southern polar Mars","authors":"M. Gergacz ,&nbsp;A. Kereszturi","doi":"10.1016/j.icarus.2024.116331","DOIUrl":"10.1016/j.icarus.2024.116331","url":null,"abstract":"<div><div>On Mars after the recession of the seasonal polar ice cap, small icy patches in shady and/or low thermal conductivity places are left behind. These regions are then illuminated by direct sunlight during the summer, warm up and in an ideal case a liquid phase could emerge. This work is surveying HiRISE images for such ice patches and found 148 images with ice patches on them out of the 730 images that fit the selection criteria of location and season. Their separation of ice from other bright patches, like clouds or lighter shades of surface layers and rocks was possible by their bluish color and strong connection to local topography Images with ice patches ranged between 140° and 200° solar longitude in the latitude band between −40° and − 60°. The diameter of the ice patches ranges between 1.5 and 300 m, and they remain on the surface even after the seasonal polar cap has passed over the area for at least the duration range of 1.5–139 Martian days. This range of duration indicates not ephemerally formed ice in the night but longer presence at the surface.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116331"},"PeriodicalIF":2.5,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315756","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 direction of core solidification in asteroids: Implications for dynamo generation","authors":"K.H. Dodds ,&nbsp;J.F.J. Bryson ,&nbsp;J.A. Neufeld ,&nbsp;R.J. Harrison","doi":"10.1016/j.icarus.2024.116319","DOIUrl":"10.1016/j.icarus.2024.116319","url":null,"abstract":"<div><div>Paleomagnetic studies of meteorites over the past two decades have revealed that the cores of multiple meteorite parent bodies, including those of certain chondritic groups, generated dynamo fields as they crystallised. However, uncertainties in the direction and mode of core solidification in asteroid-sized bodies have meant using the timings and durations of these fields to constrain parent body properties, such as size, is challenging. Here, we use updated equations of state and liquidus relationships for Fe-FeS liquids at low pressures to calculate the locations at which solids form in these cores. We perform these calculations for core-mantle boundary (CMB) pressures from 0–2 GPa, and Fe-FeS liquid concentrations on the iron-rich side of the eutectic, as well as two values of iron thermal expansivity that cover the measured uncertainties in this parameter, and adiabatic and conductive cooling of these cores. We predict inward core crystallisation from the CMB in asteroids due to their low <span><math><mi>&lt; 0.5 GPa</mi></math></span> pressures regardless of the uncertainties in other key core parameters. However, due to low internal pressures in these cores, remelting of any iron snow, as proposed to generate Ganymede’s present-day field, may be unlikely as the cores are approximately isothermal. Therefore a different mode of inward core solidification is possibly required to explain compositionally-driven dynamo action in asteroids. Additionally, we identify possible regimes at higher <span><math><mi>&gt; 0.6 − 2 GPa</mi></math></span> pressures in which crystallisation can occur concurrently at the CMB and the centre.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116319"},"PeriodicalIF":2.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319303","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":"Coupled tidal tomography and thermal constraints for probing Mars viscosity profile","authors":"Alex Guinard,&nbsp;Agnès Fienga,&nbsp;Anthony Mémin,&nbsp;Clément Ganino","doi":"10.1016/j.icarus.2024.116318","DOIUrl":"10.1016/j.icarus.2024.116318","url":null,"abstract":"<div><div>Computing the tidal deformations of Mars, we explored various Mars spherically symmetric internal structures with different types of interface between the mantle and the liquid core. By assessing their compatibility with a diverse set of geophysical observations we show that despite the very short periods of excitation, tidal deformation is very efficient to constrain Mars interior. We calculated densities and thicknesses for Martian lithosphere, mantle, core–mantle boundary layers and core and found them consistent with preexisting results from other methods. We also estimated new viscosities for these layers. We demonstrated that the geodetic records associated with thermal constraints are very sensitive to the presence of a 2-layered interface on the top of the liquid core in deep Martian mantle. This interface is composed by 2 layers of similar densities but very different viscosity and rheology: the layer on the top of the core is liquid (Newtonian, NBL) and the one at the base of the mantle, overlaying the liquid one, is an Andrade layer (ABL) with a viscosity in average 10 orders of magnitude greater than the Newtonian layer. Our results also indicate that the existence of this 2-layered interface significantly impacts the viscosity profiles of the mantle and the lithosphere. More precisely, models including the 2-layered interface do not display significant viscosity contrast between the mantle and the lithosphere, preventing mechanical decoupling between a lithosphere and the mantle immediately below. Such models are in favor of a stagnant lid regime that can be supported by the current absence of an Earth-like plate tectonics on Mars. Finally, in our results, the presence of liquid Newtonian layer at the top of the liquid core is incompatible with the existence of a solid inner core.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116318"},"PeriodicalIF":2.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0019103524003786/pdfft?md5=0c0e6dd63f31d5726acabf1dd61b4e68&pid=1-s2.0-S0019103524003786-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315818","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":"Seasonality of aeolian landforms on Meridiani Planum, Mars","authors":"J. Kozakiewicz ,&nbsp;D. Maj ,&nbsp;S. Mol ,&nbsp;M. Sobucki ,&nbsp;T. Michaels ,&nbsp;N. Frodyma","doi":"10.1016/j.icarus.2024.116325","DOIUrl":"10.1016/j.icarus.2024.116325","url":null,"abstract":"<div><div>The wind interacts with the surface of Mars, forming aeolian landforms. The orientation of these landforms informs us about the formative wind directions. The observations of the orientation of aeolian landforms on Meridiani Planum between Mars years 26 and 38 indicated that there is a seasonality of formative wind directions in this region. The studied landforms were shaped by a predominant SE wind during summer, while during winter several wind directions played a role in their formation. Throughout the Mars year, the most formative were the NW winds. The presence of dark wind streaks oriented toward the west during winter indicates that E winds occur in this season on Meridiani Planum, as previously predicted by numerical simulations. It was also found that aeolian deflation led to complete erosion of smaller dunes, and that the relatively strong deflation was responsible for the scarcity of fine-grained ripples on Meridiani Planum. In this region, fine-grained ripples were found only in a few locations, and they were mainly small bedforms with wavelengths up to several centimeters.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116325"},"PeriodicalIF":2.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142318535","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":"Size-based spectrophotometric analysis of the Polana-Eulalia Complex","authors":"L.T. McClure ,&nbsp;J.P. Emery ,&nbsp;C.A. Thomas ,&nbsp;K.J. Walsh ,&nbsp;R.K. Williams","doi":"10.1016/j.icarus.2024.116322","DOIUrl":"10.1016/j.icarus.2024.116322","url":null,"abstract":"<div><div>The Polana-Eulalia Complex (PEC) is an Inner Main Belt, C-complex asteroid population that may be the source of the near-Earth asteroid spacecraft mission targets (101955) Bennu and (162173) Ryugu. Here, we report a size-based investigation of the visible (VIS; 0.47 —0.89 μm) spectrophotometric slopes of the PEC's constituent families, the “New Polana” and Eulalia Families. Using two releases of the Sloan Digital Sky Survey's Moving Object Catalog as well as the 3rd data release of the Gaia catalog, we present evidence of size-based slope variability within each family. We find that Eulalia family members exhibit lower average slopes than Polana family members in all catalogs' samples, particularly for objects &lt;9 km in diameter. We are unable to conclude that VIS slope distinguishability between the families is statistically significant, but we explore a potential cause of the bulk slope differences between the PEC families, in addition to providing commentary on size-slope trends generally.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"425 ","pages":"Article 116322"},"PeriodicalIF":2.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315819","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}