arXiv - PHYS - Earth and Planetary Astrophysics最新文献_第4页

Analytical theory of the spin-orbit state of a binary asteroid deflected by a kinetic impactor 动能撞击器偏转双小行星自旋轨道状态的解析理论

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06534

Michalis Gaitanas, Christos Efthymiopoulos, Ioannis Gkolias, George Voyatzis, Kleomenis Tsiganis

引用次数: 0

New evidence supporting past dust ejections from active asteroid (4015) Wilson-Harrington 支持活动小行星（4015）威尔逊-哈灵顿过去尘埃喷射的新证据

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06448

Sunho Jin, Masateru Ishiguro, Jooyeon Geem, Hiroyuki Naito, Jun Takahashi, Hiroshi Akitaya, Daisuke Kuroda, Seitaro Urakawa, Seiko Takagi, Tatsuharu Oono, Tomohiko Sekiguchi, Davide Perna, Simone Ieva, Yoonsoo P. Bach, Ryo Imazawa, Koji S. Kawabata, Makoto Watanabe, Hangbin Jo

{"title":"New evidence supporting past dust ejections from active asteroid (4015) Wilson-Harrington","authors":"Sunho Jin, Masateru Ishiguro, Jooyeon Geem, Hiroyuki Naito, Jun Takahashi, Hiroshi Akitaya, Daisuke Kuroda, Seitaro Urakawa, Seiko Takagi, Tatsuharu Oono, Tomohiko Sekiguchi, Davide Perna, Simone Ieva, Yoonsoo P. Bach, Ryo Imazawa, Koji S. Kawabata, Makoto Watanabe, Hangbin Jo","doi":"arxiv-2409.06448","DOIUrl":"https://doi.org/arxiv-2409.06448","url":null,"abstract":"Context. (4015) Wilson-Harrington (hereafter, WH) was discovered as a comet\u0000in 1949 but has a dynamical property consistent with that of a near-Earth\u0000asteroid. Although there is a report that the 1949 activity is associated with\u0000an ion tail, the cause of the activity has not yet been identified. Aims. This\u0000work aims to reveal the mysterious comet-like activity of the near-Earth\u0000asteroid. Methods. We conducted new polarimetric observations of WH from May\u00002022 to January 2023, reanalyses of the photographic plate images taken at the\u0000time of its discovery in 1949, and dust tail simulation modelings, where the\u0000dust terminal velocity and ejection epoch are taken into account. Results. We\u0000found that this object shows polarization characteristics similar to those of\u0000low-albedo asteroids. We derived the geometric albedo ranging from pV = 0.076\u0000+- 0.010 to pV = 0.094 +- 0.018 from our polarimetry (the values vary depending\u0000on the data used for fitting and the slope-albedo relationship coefficients).\u0000In addition, the 1949 image showed an increase in brightness around the\u0000nucleus. Furthermore, we found that the color of the tail is consistent with\u0000sunlight, suggesting that the 1949 activity is associated with dust ejection.\u0000From the dust tail analysis, ~9 x 10^5 kg of material was ejected episodically\u0000at a low velocity equivalent to or even slower than the escape velocity.\u0000Conclusions. We conclude that WH is most likely an active asteroid of main belt\u0000origin and that the activity in 1949 was likely triggered by mass shedding due\u0000to fast rotation.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Volatile-rich Sub-Neptunes as Hydrothermal Worlds: The Case of K2-18 b 作为热液世界的富挥发性次海王星：K2-18 b的案例

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06258

Cindy N. Luu, Xinting Yu, Christopher R. Glein, Hamish Innes, Artyom Aguichine, Joshua Krissansen-Totton, Julianne I. Moses, Shang-Min Tsai, Xi Zhang, Ngoc Truong, Jonathan J. Fortney

{"title":"Volatile-rich Sub-Neptunes as Hydrothermal Worlds: The Case of K2-18 b","authors":"Cindy N. Luu, Xinting Yu, Christopher R. Glein, Hamish Innes, Artyom Aguichine, Joshua Krissansen-Totton, Julianne I. Moses, Shang-Min Tsai, Xi Zhang, Ngoc Truong, Jonathan J. Fortney","doi":"arxiv-2409.06258","DOIUrl":"https://doi.org/arxiv-2409.06258","url":null,"abstract":"Temperate exoplanets between the sizes of Earth and Neptune, known as\u0000\"sub-Neptunes\", have emerged as intriguing targets for astrobiology. It is\u0000unknown whether these planets resemble Earth-like terrestrial worlds with a\u0000habitable surface, Neptune-like giant planets with deep atmospheres and no\u0000habitable surface, or something exotic in between. Recent JWST transmission\u0000spectroscopy observations of the canonical sub-Neptune K2-18 b revealed ~1%\u0000CH4, ~1% CO2, and a non-detection of CO in the atmosphere. While previous\u0000studies have proposed that the observed atmospheric composition could help\u0000constrain the lower atmosphere conditions and determine the interior structure\u0000of sub-Neptunes like K2-18 b, the possible interactions between the atmosphere\u0000and a hot, supercritical water ocean at its base remain unexplored. In this\u0000work, we investigate whether a global supercritical water ocean, resembling a\u0000planetary-scale hydrothermal system, can explain these observations on K2-18\u0000b-like sub-Neptunes through equilibrium aqueous geochemical calculations. We\u0000find that the observed atmospheric CH4/CO2 ratio implies a minimum ocean\u0000temperature of ~715 K, whereas the corresponding CO/CO2 ratio allows ocean\u0000temperatures up to ~1060 K. These results indicate that a global supercritical\u0000water ocean on K2-18 b is plausible. While life cannot survive in this ocean,\u0000this work represents the first step towards understanding how a global\u0000supercritical water ocean may influence observable atmospheric characteristics\u0000on volatile-rich sub-Neptunes. Future observations with better constrained NH3\u0000and CO mixing ratios could further help distinguish between possible interior\u0000compositions of K2-18 b.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bulk and atmospheric metallicities as direct probes of sequentially varying accretion mechanisms of gas and solids onto planets 作为气体和固体依次变化的行星吸积机制直接探针的体积和大气金属性

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06670

Yasuhiro Hasegawa, Mark R. Swain

{"title":"Bulk and atmospheric metallicities as direct probes of sequentially varying accretion mechanisms of gas and solids onto planets","authors":"Yasuhiro Hasegawa, Mark R. Swain","doi":"arxiv-2409.06670","DOIUrl":"https://doi.org/arxiv-2409.06670","url":null,"abstract":"Core accretion is the standard scenario of planet formation, wherein planets\u0000are formed by sequential accretion of gas and solids, and is widely used to\u0000interpret exoplanet observations. However, no direct probes of the scenario\u0000have been discussed yet. Here, we introduce an onion-like model as one\u0000idealization of sequential accretion and propose that bulk and atmospheric\u0000metallicities of exoplanets can be used as direct probes of the process. Our\u0000analytical calculations, coupled with observational data, demonstrate that the\u0000trend of observed exoplanets supports the sequential accretion hypothesis. In\u0000particular, accretion of planetesimals that are $gtrsim $ 100 km in size is\u0000most favored to consistently explain the observed trends. The importance of\u0000opening gaps in both planetesimal and gas disks following planetary growth is\u0000also identified. New classification is proposed, wherein most observed planets\u0000are classified into two interior statuses: globally mixed and locally\u0000(well-)mixed. Explicit identification of the locally (well-)mixed status\u0000enables reliable verification of sequential accretion. During the JWST era, the\u0000quality and volume of observational data will increase drastically and improve\u0000exoplanet characterization. This work provides one key reference of how both\u0000the bulk and atmospheric metallicities can be used to constrain gas and solid\u0000accretion mechanisms of planets.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The HD 191939 Exoplanet System is Well-Aligned and Flat HD 191939系外行星系统排列整齐且平坦

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06795

Jack Lubin, Erik A. Petigura, Judah Van Zandt, Corey Beard, Fei Dai, Samuel Halverson, Rae Holcomb, Andrew W. Howard, Howard Isaacson, Jacob Luhn, Paul Robertson, Ryan A. Rubenzahl, Gudmundur Stefansson, Joshua N. Winn, Max Brodheim, William Deich, Grant M. Hill, Steven R. Gibson, Bradford Holden, Aaron Householder, Russ R. Laher, Kyle Lanclos, Joel Payne, Arpita Roy, Roger Smith, Abby P. Shaum, Christian Schwab, Josh Walawender

{"title":"The HD 191939 Exoplanet System is Well-Aligned and Flat","authors":"Jack Lubin, Erik A. Petigura, Judah Van Zandt, Corey Beard, Fei Dai, Samuel Halverson, Rae Holcomb, Andrew W. Howard, Howard Isaacson, Jacob Luhn, Paul Robertson, Ryan A. Rubenzahl, Gudmundur Stefansson, Joshua N. Winn, Max Brodheim, William Deich, Grant M. Hill, Steven R. Gibson, Bradford Holden, Aaron Householder, Russ R. Laher, Kyle Lanclos, Joel Payne, Arpita Roy, Roger Smith, Abby P. Shaum, Christian Schwab, Josh Walawender","doi":"arxiv-2409.06795","DOIUrl":"https://doi.org/arxiv-2409.06795","url":null,"abstract":"We report the sky-projected spin-orbit angle $lambda$ for HD 191939 b, the\u0000innermost planet in a 6 planet system, using Keck/KPF to detect the\u0000Rossiter-McLaughlin (RM) effect. Planet b is a sub-Neptune with radius 3.4\u0000$pm$ 0.8 R$_{oplus}$ and mass 10.0 $pm$ 0.7 M$_{oplus}$ with an RM\u0000amplitude $<$1 ms$^{-1}$. We find the planet is consistent with a well-aligned\u0000orbit, measuring $lambda= , $ 3.7 $pm$ 5.0 degrees. Additionally, we place\u0000new constraints on the mass and period of the distant super-Jupiter, planet f,\u0000finding it to be 2.88 $pm$ 0.26 $M_J$ on a 2898 $pm$ 152 day orbit. With\u0000these new orbital parameters, we perform a dynamical analysis of the system and\u0000constrain the mutual inclination of the non-transiting planet e to be smaller\u0000than 12 degrees relative to the plane shared by the inner three transiting\u0000planets. Additionally, the further planet f is inclined off this shared plane,\u0000the greater the amplitude of precession for the entire inner system, making it\u0000increasingly unlikely to measure an aligned orbit for planet b. Through this\u0000analysis, we show that this system's wide variety of planets are all\u0000well-aligned with the star and nearly co-planar, suggesting that the system\u0000formed dynamically cold and flat out of a well-aligned proto-planetary disk,\u0000similar to our own solar system.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

FAST Observations of Four Comets to Search for the Molecular Line Emissions between 1.0 and 1.5 GHz Frequencies 对四颗彗星进行 FAST 观测以搜索 1.0 和 1.5 千兆赫频率之间的分子线发射

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06227

Long-Fei Chen, Chao-Wei Tsai, Jian-Yang Li, Bin Yang, Di Li, Yan Duan, Chih-Hao Hsia, Zhichen Pan, Lei Qian, Donghui Quan, Xue-Jian Jiang, Xiaohu Li, Ruining Zhao, Pei Zuo

{"title":"FAST Observations of Four Comets to Search for the Molecular Line Emissions between 1.0 and 1.5 GHz Frequencies","authors":"Long-Fei Chen, Chao-Wei Tsai, Jian-Yang Li, Bin Yang, Di Li, Yan Duan, Chih-Hao Hsia, Zhichen Pan, Lei Qian, Donghui Quan, Xue-Jian Jiang, Xiaohu Li, Ruining Zhao, Pei Zuo","doi":"arxiv-2409.06227","DOIUrl":"https://doi.org/arxiv-2409.06227","url":null,"abstract":"We used the Five-hundred-meter Aperture Spherical radio Telescope (FAST) to\u0000search for the molecular emissions in the L-band between 1.0 and 1.5 GHz toward\u0000four comets, C/2020 F3 (NEOWISE), C/2020 R4 (ATLAS), C/2021 A1 (Leonard), and\u000067P/Churyumov-Gerasimenko during or after their perihelion passages. Thousands\u0000of molecular transition lines fall in this low-frequency range, many attributed\u0000to complex organic or prebiotic molecules. We conducted a blind search for the\u0000possible molecular lines in this frequency range in those comets and could not\u0000identify clear signals of molecular emissions in the data. Although several\u0000molecules have been detected at high frequencies of great than 100 GHz in\u0000comets, our results confirm that it is challenging to detect molecular\u0000transitions in the L-band frequency ranges. The non-detection of L-band\u0000molecular lines in the cometary environment could rule out the possibility of\u0000unusually strong lines, which could be caused by the masers or non-LTE effects.\u0000Although the line strengths are predicted to be weak, for FAST, using the\u0000ultra-wide bandwidth receiver and improving the radio frequency interference\u0000environments would enhance the detectability of those molecular transitions at\u0000low frequencies in the future.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Slow Rotation for the Super-Puff Planet Kepler-51d 超级泡芙行星开普勒-51d的缓慢自转

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-10 DOI: arxiv-2409.06697

Caleb Lammers, Joshua N. Winn

{"title":"Slow Rotation for the Super-Puff Planet Kepler-51d","authors":"Caleb Lammers, Joshua N. Winn","doi":"arxiv-2409.06697","DOIUrl":"https://doi.org/arxiv-2409.06697","url":null,"abstract":"Super-puffs are low-density planets of unknown origin and composition. If\u0000they form by accreting nebular gas through a circumplanetary disk, one might\u0000expect super-puffs to be spinning quickly. Here, we derive upper limits on the\u0000rotational oblateness of the super-puff Kepler-51d, based on precise transit\u0000observations with the NIRSpec instrument aboard the James Webb Space Telescope.\u0000The absence of detectable oblateness-related anomalies in the light curve leads\u0000to an upper limit of about $0.15$ on the planet's sky-projected oblateness.\u0000Assuming the sky-projected oblateness to be representative of the true\u0000oblateness, the rotation period of Kepler-51d is $gtrsim 40$ hours, or\u0000equivalently, its rotation speed is $lesssim 42%$ of the breakup speed.\u0000Alternatively, if the apparently low density of Kepler-51d is due to an opaque\u0000planetary ring, the ring must be oriented within $27deg$ of face-on and have\u0000an inner radius smaller than $1.2$ times the planet's radius. The lack of\u0000anomalies exceeding $0.01%$ in the ingress and egress portions of the light\u0000curve also places a constraint on the model of Wang & Dai, in which the\u0000planet's apparently low density is due to a dusty outflowing atmosphere.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"403 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Formation of Close-in Neptunes Around Low-Mass Stars Through Breaking Resonant Chains 通过打破共振链在低质量恒星周围形成近邻海王星

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-09 DOI: arxiv-2409.05748

Donald Liveoak, Sarah Millholland

{"title":"Formation of Close-in Neptunes Around Low-Mass Stars Through Breaking Resonant Chains","authors":"Donald Liveoak, Sarah Millholland","doi":"arxiv-2409.05748","DOIUrl":"https://doi.org/arxiv-2409.05748","url":null,"abstract":"Conventional planet formation theories predict a paucity of massive planets\u0000around small stars, especially very low-mass ($0.1 - 0.3 M_{odot}$)\u0000mid-to-late M dwarfs. Such tiny stars are expected to form planets of\u0000terrestrial sizes, but not much bigger. However, this expectation is challenged\u0000by the recent discovery of LHS 3154 b, a planet with period of 3.7 days and\u0000minimum mass of $13.2 M_{oplus}$ orbiting a $0.11 M_{odot}$ star. Here,\u0000we propose that close-in Neptune-mass planets like LHS 3154 b formed through an\u0000anomalous series of mergers from a primordial compact system of super-Earths.\u0000We perform simulations within the context of the \"breaking the chains\"\u0000scenario, in which super-Earths initially form in tightly-spaced chains of\u0000mean-motion resonances before experiencing dynamical instabilities and\u0000collisions. Planets as massive and close-in as LHS 3154 b ($M_p sim 12 - 20 \u0000M_{oplus}$, $P < 7$ days) are produced in $sim$1% of simulated systems, in\u0000broad agreement with their low observed occurrence. These results suggest that\u0000such planets do not require particularly unusual formation conditions but\u0000rather are an occasional byproduct of a process that is already theorized to\u0000explain compact multi-planet systems. Interestingly, our simulated systems with\u0000LHS 3154 b-like planets also contain smaller planets at around $sim 30$ days,\u0000offering a possible test of this hypothesis.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Short-Timescale Spatial Variability of Ganymede's Optical Aurora Ganymede 的光学极光的短时空间变异性

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-09 DOI: arxiv-2409.06055

Zachariah Milby, Katherine de Kleer, Carl Schmidt, François Leblanc

{"title":"Short-Timescale Spatial Variability of Ganymede's Optical Aurora","authors":"Zachariah Milby, Katherine de Kleer, Carl Schmidt, François Leblanc","doi":"arxiv-2409.06055","DOIUrl":"https://doi.org/arxiv-2409.06055","url":null,"abstract":"Ganymede's aurora are the product of complex interactions between its\u0000intrinsic magnetosphere and the surrounding Jovian plasma environment and can\u0000be used to derive both atmospheric composition and density. In this study, we\u0000analyzed a time-series of Ganymede's optical aurora taken with Keck I/HIRES\u0000during eclipse by Jupiter on 2021-06-08 UTC, one day after the Juno flyby of\u0000Ganymede. The data had sufficient signal-to-noise in individual 5-minute\u0000observations to allow for the first high cadence analysis of the spatial\u0000distribution of the aurora brightness and the ratio between the 630.0 and 557.7\u0000nm disk-integrated auroral brightnesses -- a quantity diagnostic of the\u0000relative abundances of O, O$_2$ and H$_2$O in Ganymede's atmosphere. We found\u0000that the hemisphere closer to the centrifugal equator of Jupiter's\u0000magnetosphere (where electron number density is highest) was up to twice as\u0000bright as the opposing hemisphere. The dusk (trailing) hemisphere, subjected to\u0000the highest flux of charged particles from Jupiter's magnetosphere, was also\u0000consistently almost twice as bright as the dawn (leading) hemisphere. We\u0000modeled emission from simulated O$_2$ and H$_2$O atmospheres during eclipse and\u0000found that if Ganymede hosts an H$_2$O sublimation atmosphere in sunlight, it\u0000must collapse on a faster timescale than expected to explain its absence in our\u0000data given our current understanding of Ganymede's surface properties.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Infrared Compositional Measurements in Comet C/2017 K2 (Pan-STARRS) at Heliocentric Distances Beyond 2.3 AU 日心距离超过 2.3 AU 时 C/2017 K2 彗星（Pan-STARRS）的红外成分测量结果

arXiv - PHYS - Earth and Planetary Astrophysics Pub Date : 2024-09-09 DOI: arxiv-2409.05789

Chemeda Ejeta, Erika Gibb, Michael A. DiSanti, Hideyo Kawakita, Boncho P. Bonev, Neil Dello Russo, Nathan Roth, Younas Khan, Adam J. McKay, Michael R. Combi, Lori Feaga, Mohammad Saki, Ronald J. Vervack Jr., Yinsi Shou

{"title":"Infrared Compositional Measurements in Comet C/2017 K2 (Pan-STARRS) at Heliocentric Distances Beyond 2.3 AU","authors":"Chemeda Ejeta, Erika Gibb, Michael A. DiSanti, Hideyo Kawakita, Boncho P. Bonev, Neil Dello Russo, Nathan Roth, Younas Khan, Adam J. McKay, Michael R. Combi, Lori Feaga, Mohammad Saki, Ronald J. Vervack Jr., Yinsi Shou","doi":"arxiv-2409.05789","DOIUrl":"https://doi.org/arxiv-2409.05789","url":null,"abstract":"Comet C/2017 K2 (Pan-STARRS) provided a rare opportunity to investigate the\u0000evolution of coma composition and outgassing patterns over a transitional\u0000heliocentric distance (Rh) range where activity drivers in comets are thought\u0000to change from \"hypervolatile\" (CO, CH$_4$, C$_2$H$_6$, and/or\u0000CO$_2$)-dominated to H2O-dominated. We performed high-resolution,\u0000cross-dispersed, near-infrared spectroscopy of C/2017 K2 with iSHELL at the\u0000NASA Infrared Telescope Facility (IRTF) and NIRSPEC at the W. M. Keck 2\u0000Observatory. We report gas rotational temperatures (Trot) and molecular\u0000production rates (Q; mol/s) or upper limits for the hypervolatile species\u0000CH$_4$, CO, and C$_2$H$_6$, together with less volatile ices (CH$_3$OH, H$_2$O,\u0000HCN, C$_2$H$_2$, NH$_3$, and OCS) over a range of pre-perihelion distances, Rh=\u00003.15 - 2.35 au. We also report (or stringently constrain) abundance ratios\u0000(mixing ratios) of the targeted species with respect to CO, C$_2$H$_6$, and\u0000(when detected) H$_2$O. All volatiles were enriched relative to water in C/2017\u0000K2 when compared to their mean values among Oort Cloud comets, whereas\u0000abundances relative to C2H6 were consistent with their average values from\u0000other long-period comets.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0