Icarus最新文献

{"title":"Investigating formation processes of secondary sulfate minerals in the semi-arid climate of the Rio Puerco watershed, New Mexico using sulfur and oxygen isotopes – Implications for the origin of gypsum veins in Gale crater on Mars","authors":"Ivy Ettenborough,&nbsp;Anna Szynkiewicz","doi":"10.1016/j.icarus.2024.116384","DOIUrl":"10.1016/j.icarus.2024.116384","url":null,"abstract":"<div><div>Secondary sulfate minerals are common throughout the sedimentary deposits of Mount Sharp, located within Gale crater on Mars. However, the source of sulfate (SO₄²⁻) and past climatic conditions during their formation are not well understood. Therefore, we investigated the δ³⁴S, δ¹⁸O, and δ²H of gypsum veins and other Mg- and Ca- sulfates forming as salt crusts and cement within the shallow sediments of the Rio Puerco watershed in central New Mexico. The δ³⁴S values of vein gypsum and acid-soluble SO₄²⁻ (cement) varied over the same range (−33.3 to −12.9 ‰ and −34.6 to −12.1 ‰, respectively), which was similar to the δ³⁴S of bedrock sulfide minerals (−37.4 to −5.9 ‰). This implies that sulfide oxidation is the main source of SO₄²⁻ in the Rio Puerco aqueous system. The measured δ¹⁸O values of SO₄²⁻ (−8.9 to +3.1 ‰) as well as δ¹⁸O and δ²H values of gypsum hydration water (−8.9 to +0.6 ‰, and −112 to −82 ‰, respectively) overlapped with the isotope composition of local meteoric precipitation, suggesting that sulfide oxidation to SO₄²⁻ and gypsum formation have occurred under semi-arid climate conditions. The isotope results suggest the top-down infiltration of meteoric water leads to leaching of SO₄²⁻, Mg⁺, and Ca²⁺ from bedrock sulfide weathering followed by abundant formation of Mg- and Ca-sulfates in surface deposits and gypsum veins with depth. Because of spatial and mineralogical similarities in the secondary Mg- and Ca-sulfate mineral occurrences, we hypothesize that chemical weathering of sulfide minerals could have been the main source of SO₄²⁻ in the aqueous system of Gale crater.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"428 ","pages":"Article 116384"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759678","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":"Rotation period estimates for 14 asteroids with the Earth MOID less than 1.1 AU","authors":"Ilgmars Eglitis,&nbsp;Darja Svincicka","doi":"10.1016/j.icarus.2024.116380","DOIUrl":"10.1016/j.icarus.2024.116380","url":null,"abstract":"<div><div>In the present study, the Lomb–Scargle Scargle (L–S) method was employed for the analysis of brightness measurements from multiple observatories as published in the Minor Planet Center (MPC) circulars, as well as brightness measurements from the Baldone Observatory, to determine the periods of asteroids. The periods of fifteen asteroids were determined. The research yielded results for both asteroids with previously known periods and those without listed periods in the ALCDEF lightcurve database. The results revealed the potential for this approach to be used in the subsequent identification of yet-unknown periods of asteroids. This was demonstrated by the confirmation of periods for four of the five asteroids with known periods from the ALCDEF lightcurve database, namely 1951, 1963, 2134 and 2150. In the case of the fifth asteroid, 2174, for which a previously determined rotation period had been provided, an additional, possible shorter rotation period was identified. As has been shown, the use of the L–S method in conjunction with independent analysis of many series of brightness measurements from different observatories is a suitable approach, even for a small series of samples of brightness observations unevenly spread over a long time, for the determination of periods. Furthermore, this approach is effective even when there are significant intervals between measurements, which is not the case with the classical Fourier method. Additionally, the exclusion of observations that deviate significantly from the linear relationship of the phase diagram, by the three-sigma criterion, markedly enhanced the efficacy and precision of the method. As a result, periods were identified for the first time for asteroids 1779, 1818, 2128, 2318, 2497, 2503, 2538, 2539, and 2583.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"428 ","pages":"Article 116380"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745842","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":"322P/SOHO: The counterpart of a historical comet in 254 CE?","authors":"Jianhua Cui,&nbsp;Geng Li,&nbsp;Yongheng Zhao","doi":"10.1016/j.icarus.2024.116382","DOIUrl":"10.1016/j.icarus.2024.116382","url":null,"abstract":"<div><div>The historical observations of East Asia provide a systematic and accurate record of bright periodic comets and could help us understand their past states. However, except for these comets, few other comets have been successfully associated with historical observations. Here we report that the sunskirter 322P/SOHO is probably associated with a historical comet in 254 CE, although it appeared no visible cometary activity in recent observations. By analyzing astrometric data from the IAU Minor Planet Center, we determine the orbit of 322P and suggest that its motion is affected by non-gravitational forces based on sodium sublimation, indicating its high devolatilization. The orbital integration shows that the position and perihelion date of 322P are highly corresponding to a historical comet in 254 CE. This comet had an extremely long tail that stretched across the sky, indicating the intense activity outburst. The dynamical properties of 322P and its similarity to dark comets suggests that it possibly originated from a volatile object in the main belt, but has undergone the rotational splitting and devolatilization. Previous studies have also suggested the possible splitting. Given that splitting is a common cause of activity outburst, we suggest that 322P might have experienced a fragmentation in 254 CE and released a large amount of material, which led to the spectacular tail and devolatilization. Only faint sodium-driven activity remained afterwards, which could explain the lack of historical observations after 254 CE.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"429 ","pages":"Article 116382"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757600","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":"Where on the Moon was the eruption that produced the recently reported ∼ 120 million year old volcanic glass beads?","authors":"James W. Head ,&nbsp;Lionel Wilson ,&nbsp;Yuqi Qian","doi":"10.1016/j.icarus.2024.116378","DOIUrl":"10.1016/j.icarus.2024.116378","url":null,"abstract":"<div><div>Three anomalously young, ∼120 Ma old lunar mare pyroclastic beads have recently been reported (Wang et al., 2024) from Chang'e-5 (CE-5 soils, particularly distinguished from impact melt beads by sulfur isotope (³⁴S/³²S) composition and correlations with sulfur concentration. We examine lunar pyroclastic eruption theory and candidate eruption conditions in order to locate the vent and assess its geological context, finding that the estimated maximum pyroclast dispersal range from a candidate source vent is likely to be ∼200 km, placing it within the area of the CE-5–2.0 Ga sampled Em4 unit. The greatest predicted dispersal distances are associated with an explosive eruption from a stalled dike several kilometers below the surface, creating an elongated, multi-km-scale pit crater potentially surrounded by a dark pyroclastic ring. We assessed the Chang'e-5 region for such candidates and found none. This raises the possibility that the ∼120 Ma pyroclastic beads might have been delivered to the site from an impact crater outside Em4, but the most likely candidates are sufficiently large and at such great distances that they are likely to have reset the ages of any young pyroclastic beads thus delivered. Lacking a clear source for extraordinarily young pyroclastic beads, we reassess the possibility that the ∼120 Ma beads may be of local impact melt origin. Evidence favoring this hypothesis includes the abundant CE-5 impact glass bead ages in the 100–200 Ma year range previously reported (Long et al., 2022), and the similarities in composition and characteristics of the three beads and those of local impact origin. To address these conundra, further regional searches for a source vent and continued geochemical characterization and dating of CE-5 regolith glass beads should be undertaken.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"428 ","pages":"Article 116378"},"PeriodicalIF":2.5,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745837","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":"Quasi-Biennial Oscillation absent in Mars atmospheric reanalysis datasets","authors":"J. Michael Battalio","doi":"10.1016/j.icarus.2024.116367","DOIUrl":"10.1016/j.icarus.2024.116367","url":null,"abstract":"<div><div>Mars’s atmosphere shares many of the same types of oscillations exhibited in Earth’s climate, like the Semiannual Oscillation and Annular Modes, but using two Martian reanalysis datasets derived from Mars Climate Sounder observations, we find that Mars fails to generate a Quasi-Biennial Oscillation (QBO). The lack of a QBO may stem from the absence of a stratosphere on Mars — as the background flow is critical for setting the altitude that vertically propagating waves deposit momentum — or the extreme latitudinal variation of the overturning circulation disrupts waves sources. The lack of a QBO on Mars may enable unique comparisons between Earth’s and Mars’s atmospheres.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"427 ","pages":"Article 116367"},"PeriodicalIF":2.5,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A note on the direction of core solidification in asteroids, the iron melting curve, and phase equilibria parameterizations","authors":"Q. Williams","doi":"10.1016/j.icarus.2024.116381","DOIUrl":"10.1016/j.icarus.2024.116381","url":null,"abstract":"<div><div>The accuracy of the pressure/temperature/composition parameterization of Buono and Walker (2011) to describe the liquidus of iron and the Fe-FeS system is examined. In the pressure range critical for asteroidal core crystallization (0- ∼2 GPa), the model predicts a shape for the iron melting curve (initially negatively sloped, and turning over near 0.7 GPa) that is inconsistent with previous experimental observations, thermodynamic constraints, and millennia of empirical metallurgical observations. Dodds et al. (2025) recently used this model to derive notable conclusions about the behavior of the solidifying cores of asteroids: the robustness of their conclusions is assessed. Two basic caveat emptor guidelines for employing parameterizations of phase equilibria data are suggested: (1) ensure that the model's fit is consistent with simple thermodynamic expectations; and (2) verify that the data used to formulate the model provide adequate coverage in the region of interest.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"427 ","pages":"Article 116381"},"PeriodicalIF":2.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706041","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":"Lifetime, size and emission of laser-induced plasmas for in-situ laser-induced breakdown spectroscopy on Earth, Mars and Moon","authors":"Fabian Seel ,&nbsp;Susanne Schröder ,&nbsp;Elise Clavé ,&nbsp;Enrico Dietz ,&nbsp;Peder Bagge Hansen ,&nbsp;Kristin Rammelkamp ,&nbsp;Heinz-Wilhelm Hübers","doi":"10.1016/j.icarus.2024.116376","DOIUrl":"10.1016/j.icarus.2024.116376","url":null,"abstract":"<div><div>The spectroscopic technique of laser-induced breakdown spectroscopy (LIBS) is a powerful method to perform rapid chemical analysis of geologic samples with short measurement times and no need for sample preparation. After the ChemCam instrument aboard NASA’s MSL rover proved its suitability for space missions that explore planetary surfaces in 2012, the interest in LIBS instruments as payloads has grown and several subsequent missions have successfully used this technique since. The characteristics of a LIBS plasma depend on experimental and environmental parameters as well as on sample properties, including atmospheric conditions, laser irradiance and sample lithology. Consequently, LIBS instruments need to be designed and optimized specifically for each use case to maximize their science output. To aid in the development of new LIBS instruments for space exploration, we investigate the influence of atmospheric conditions, laser irradiance and sample lithology on the lifetime, size and emission of laser-induced plasmas. In our measurements, we use a plasma imaging setup with high temporal resolution of down to 2<!--> <!-->ns to investigate the evolution of the plasma from its ignition to its decay. We present a comparable data set recorded at terrestrial, Martian and airless atmospheric conditions, covering irradiances between 0.79<!--> <!-->GW/mmˆ2 and 1.43<!--> <!-->GW/mmˆ2 and samples with diverse properties, namely basalt and soapstone, as well as the lunar regolith simulants LHS-1 and LMS-1. Our measurements show the strong influence of atmospheric conditions on the plasma size and emission, while the lithologies and laser irradiances covered in this work play a minor role. This shows that instruments designed to work at certain atmospheric conditions can be used for a range of laser parameters and sample properties. Furthermore, we demonstrate that the decay of the plasma emission and the expansion of the plasma plume parallel to the sample surface can be described well by a power law and a drag model, respectively.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"427 ","pages":"Article 116376"},"PeriodicalIF":2.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706042","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":"Growth of amorphous ice grains by sintering in a protoplanetary disk","authors":"Sin-iti Sirono","doi":"10.1016/j.icarus.2024.116370","DOIUrl":"10.1016/j.icarus.2024.116370","url":null,"abstract":"<div><div>An icy grain in a protoplanetary nebula mainly consists of amorphous H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O ice and can grow through the migration of H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O molecules (sintering). The growth rate through sintering strongly depends on the diffusion constant of H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O molecules. I estimated the size of amorphous ice grains as a function of the sintering duration based on the diffusion constant of amorphous ice determined by the molecular dynamics simulation. It has been found that the growth proceeds in a wide disk region (<span><math><mrow><mo>∼</mo><mn>20</mn><mspace></mspace></mrow></math></span>AU), and grain can grow to <span><math><mrow><mo>∼</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup><mspace></mspace></mrow></math></span>cm around the snowline. The growth of the icy grains can affect the evolution of the icy dust aggregates in a protoplanetary disk.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"427 ","pages":"Article 116370"},"PeriodicalIF":2.5,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706044","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":"The extent of formation of organic molecules in the comae of comets showing relatively high activity","authors":"Sana Ahmed ,&nbsp;Kinsuk Acharyya","doi":"10.1016/j.icarus.2024.116374","DOIUrl":"10.1016/j.icarus.2024.116374","url":null,"abstract":"<div><div>Comets are a rich reservoir of complex organic molecules. Ground and space-based observatories have recently greatly enhanced the cometary molecular inventory. Although these molecules’ origin is believed to be the cometary nucleus, they can be partially synthesized in the coma. We studied organic molecules’ nucleus versus coma origins for various initial conditions, using a multifluid chemical-hydrodynamical model and an updated chemical network. For the study, we considered four comets [C/1996 B2 (Hyakutake), C/2012 F6 (Lemmon), C/2013 R1 (Lovejoy), and C/2014 Q2 (Lovejoy)] due to their relatively high activity and observation of large number of organic species. We emphasized on the C-H-O and N-bearing species, including the simplest amino acid, glycine. We discuss the formation pathways of the organics and the conditions for their formation in the coma and find that the abundance varies from one comet to another due to differences in the initial conditions, relative abundances of the reactants and temperature. We compare the organic abundances when they are present as parent volatiles to their formation solely due to gas-phase chemistry. Their abundance purely due to the coma chemistry is moderately to significantly lower compared to that when they are parent volatiles. However, we find that the production rates of some of the coma-synthesized organic molecules can reach peak values of <span><math><mrow><mo>∼</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>22</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>26</mn></mrow></msup></mrow></math></span> molecules s⁻¹, which is in the realm of detection by in situ/space-based observations, and can therefore be important considering future missions to comets. We also compare our modeled abundances with those observed in 67P/C-G by <em>Rosetta</em>, which detected several organics at a large heliocentric distance and low production rate.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"427 ","pages":"Article 116374"},"PeriodicalIF":2.5,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706114","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":"Schumann Resonances as a tool to constrain the depth of Titan’s buried water ocean: Re-assessment of Huygens observations and preparation of the EFIELD/Dragonfly experiment","authors":"Paul Lagouanelle,&nbsp;Alice Le Gall","doi":"10.1016/j.icarus.2024.116372","DOIUrl":"10.1016/j.icarus.2024.116372","url":null,"abstract":"<div><div>Among the lines of evidence for a buried ocean on Titan is the possible detection of Schumann-like Resonances (SR), in 2005, by the Permittivity, Wave and Altimetry (PWA) analyzer on board the ESA Huygens probe. SR are Extremely Low Frequency electromagnetic waves resonating between two electrically conductive layers. On Titan, it has been proposed that they propagate between the moon’s ionosphere and a salty subsurface water ocean. Their characterization by electric field sensors can provide constraints on Titan’s cavity characteristics and in particular on the depth of Titan’s ocean which is key to better assess Titan’s habitability. For this work we have developed a numerical model of Titan’s electromagnetic cavity as well as a surrogate model (i.e., an approximate mathematical model) able to accurately approximate the behavior of the cavity. This surrogate model can be used to conduct simulations and sensitivity analyses at a low computational cost. It is used both to re-assess PWA/Huygens measurements and to predict the future performance of the EFIELD experiment on board the NASA Dragonfly mission. We demonstrate that the PWA/Huygens measurements, in particular due to their low spectral resolution, do not bring any meaningful constraint on Titan’s ocean depth. On the other hand, the finer resolution of the EFIELD experiment and its ability to capture several harmonics of SR should provide more robust constraints on Titan’s internal structure, especially if the electrical properties of the ice crust and the atmosphere can be better constrained.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"428 ","pages":"Article 116372"},"PeriodicalIF":2.5,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745838","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}