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National Science Review 2022年第11期9卷 121-129页

作者：肖潇俞硕然黄俊张熇张有为肖龙 State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences Planetary Science InstituteChina University of Geosciences State Key Laboratory of Lunar and planetary Sciences Macau University of Science and Technology Chinese Academy of Sciences center for excellence in comparative Planetology China Academy of Space Technology

Temperature probes onboard the Chang’E-4(CE-4) spacecraft provide the first in situ regolith temperature measurements from the far side of the Moon. We present these temperature measurements with a customized thermal model and reveal the particle size of the lunar regolith at the CE-4 landing site to be～15 μm on average over depth, which indicates an immature regolith below the surface. In addition, the conductive component of thermal conductivity is measured as ～1.53 × 10–3W m–1K–1on the surface and～8.48 × 10–3W m–1K–1at a depth of 1 m. The average bulk density is ～471 kg m–3on the surface and～824 kg m–3in the upper 30 cm of the lunar regolith. These thermophysical properties provide important additional ’ground truth’ at the lunar far side, which is critical for the future analysis and interpretation of global temperature observations.

关键词： Chang’E-4 lunar far side regolith temperature thermal conductivity

Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath

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Earth and planetary Physics 2024年第1期8卷 47-58页

作者： Jin Guo TianRan Sun San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS center for excellence in comparative Planetology/CAS Key Lab of Geospace Environment University of Science and Technology of ChinaHefei 230026China Collaborative innovation center of Astronautical Science and Technology Harbin 150001China National Space Science center Chinese Academy of SciencesBeijing 100190China Physics Department Auburn UniversityAuburnALUSA

Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the *** X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a *** performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic *** all cases,magnetic reconnection occurs at low latitude *** soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the *** X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray ***,the magnetopause boundary can be identified using multiple viewing *** also find that solar wind conditions have little effect on the magnetopause *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

关键词： magnetopause X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation

Wavelike perturbations in Titan’s ionosphere and their compositional variation:A preliminary survey of Cassini Ion Neutral Mass Spectrometer measurements

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Earth and planetary Physics 2022年第6期6卷 522-528页

作者： ShiQi Wu DanDan Niu WeiQin Sun XiaoShu Wu HaoYu Lu Jun Cui School of Space and Environment Beihang UniversityBeijing 100191China Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518055GuangdongChina planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082GuangdongChina center for excellence in comparative Planetology Chinese Academy of SciencesHefei 230026China

Wavelike perturbations in the ionosphere of Titan,the largest satellite of Saturn,are explored based on the Cassini Ion Neutral Mass Spectrometer(INMS)*** wavelike perturbations are identified for more than twenty ion species,from simple ones such as N^(+)and CH_(4)^(+)to complex ones such as C_(2)H_(3)CNH^(+)and C_(4)H_(7)^(+).Simultaneous wavelike perturbations in background N_(2),indicative of atmospheric gravity waves,are also observed,motivating us to speculate that the INMS-derived ion perturbations are *** amplitudes of the ion perturbations are found to be larger than that of the N_(2)*** compositional variation is revealed by the data:heavier ion species exhibit greater *** observations might be understood based on considerations either of force balance or chemical loss in Titan’s ionosphere.

关键词： Titan atmospheric gravity waves ionospheric perturbations ionospheric composition Cassini

Response of photoelectron peaks in the Martian ionosphere to solar EUV/X-ray irradiance

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Earth and planetary Physics 2020年第4期4卷 390-395页

作者： XiaoShu Wu Jun Cui YuTian Cao WeiQin Sun Qiong Luo BinBin Ni National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519082China Chinese Academy of Sciences center for excellence in comparative Planetology Hefei 230026China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430074China

An important population of the dayside Martian ionosphere are photoelectrons that are produced by solar Extreme Ultraviolet and X-ray ionization of atmospheric neutrals.A typical photoelectron energy spectrum is characterized by a distinctive peak near 27 eV related to the strong solar HeⅡ emission line at 30.4 nm,and an additional peak near 500 eV related to O Auger *** this study,the extensive measurements made by the Solar Wind Electron Analyzer on board the recent Mars Atmosphere and Volatile Evolution spacecraft are analyzed and found to verify the scenario that Martian ionosphere photoelectrons are driven by solar *** report that the photoelectron intensities at the centers of both peaks increase steadily with increasing solar ionizing flux below 90 nm and that the observed solar cycle variation is substantially more prominent near the O Auger peak than near the HeⅡ *** latter observation is clearly driven by a larger variability in solar irradiance at shorter *** the solar ionizing flux increases from 1 mW·m^-2 to 2.5 mW·m^-2,the photoelectron intensity increases by a factor of 3.2 at the HeⅡ peak and by a much larger factor of 10.5 at the O Auger peak,both within the optically thin regions of the Martian atmosphere.

关键词： Mars ionosphere photoelectron solar irradiance MAVEN

Statistics matters in interpretations of non-traditional stable isotopic data

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Acta Geochimica 2020年第2期39卷 271-279页

作者： Chun-Hui Li CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026AnhuiChina CAS center for excellence in comparative Planetology Hefei 230026AnhuiChina

Increasing volumes of of non-traditional stable isotope data have brought new opportunities to gain important insights into geochemical and planetary ***,there is a worrysome trend that the isotopic data are interpreted in a fashion that its statistical approaches are chosen *** communication summarizes the rules regarding calculating the mean,standard deviation and relative standard deviation of a population,as well as error propagation and significant *** rules should be used when reporting geochemical data,especially for isotope *** two examples,I show that statistics matters in isotopic data interpretation.

关键词： Isotopic data processing Error propagation Significant digits Difference between means with uncertainties

A tale of planet formation: from dust to planets

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Research in Astronomy and Astrophysics 2020年第10期20卷 249-286页

作者： Beibei Liu Jianghui Ji Zhejiang Institute of Modern Physics Department of Physics&Zhejiang University-Purple Mountain Observatory Joint Research Center for AstronomyZhejiang UniversityHangzhou 310027China Department of Astronomy and Theoretical Physics Lund ObservatoryBox 43SE-22100Sweden CAS Key Laboratory of planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China CAS center for excellence in comparative Planetology Hefei 230026China

The characterization of exoplanets and their birth protoplanetary disks has enormously advanced in the last *** from that,our global understanding of the planet formation processes has been substantially *** this review,we first summarize the cutting-edge states of the exoplanet and disk *** further present a comprehensive panoptic view of modern core accretion planet formation scenarios,including dust growth and radial drift,planetesimal formation by the streaming instability,core growth by planetesimal accretion and pebble *** discuss the key concepts and physical processes in each growth stage and elaborate on the connections between theoretical studies and observational ***,we point out the critical questions and future directions of planet formation studies.

关键词： planets and satellites:general planets and satellites:formation planets and satellites:dynamical evolution and stability protoplanetary disks

Theoretical and numerical studies of chorus waves: A review

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Science China Earth Sciences 2020年第1期63卷 78-92页

作者： Xin TAO Fulvio ZONCA Liu CHEN Yifan WU CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS center for excellence in comparative Planetology Hefei 230026China ENEA Centro Ricerche Frascati CP 65-00044 FrascatiItaly Institute of Fusion Theory and Simulation and Department of Physics Zhejiang UniversityHangzhou 310027China Department of Physics and Astronomy University of CaliforniaIrvineCA 92697USA

Theoretical and numerical models of chorus waves are reviewed in this paper. Specifically, we focus on the nonlinear wave particle interactions and the current understanding of the frequency chirping of rising tone chorus waves. Various other related topics, such as the optimal excitation condition of chorus, the formation of subpackets, and the non-adiabaticity of the nonlinear interaction are also discussed. We end this review paper with a short list of questions of chorus waves that are still under research and debate.

关键词： Chorus waves Frequency chirping Triggered emissions

The anisotropy of suprathermal electrons in the Martian ionosphere

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Earth and planetary Physics 2024年第3期8卷 459-471页

作者： YuTian Cao Jun Cui XiaoShu Wu WenJun Liang RuiQi Fu HaoYu Lu planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China Key Laboratory of Geospace Environment University of Science&Technology of ChinaChinese Academy of SciencesHefei 230026China center for excellence in comparative Planetology Chinese Academy of SciencesHefei 230026China School of Space and Environment Beihang UniversityBeijing 102206China

Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth investigation of the pitch angle distribution of suprathermal electrons at two representative energies, 19−55 eV and 124−356 eV, using the extensive measurements made by the Solar Wind Electron Analyzer on board the Mars Atmosphere and Volatile Evolution. Throughout the study, we focus on the overall degree of anisotropy, defined as the standard deviation of suprathermal electron intensity among different directions which is normalized by the mean omni-directional intensity. The available data reveal the following characteristics: (1) In general, low energy electrons are more isotropic than high energy electrons, and dayside electrons are more isotropic than nightside electrons;(2) On the dayside, the anisotropy increases with increasing altitude at low energies but remains roughly constant at high energies, whereas on the nightside, the anisotropy decreases with increasing altitude at all energies;(3) Electrons tend to be more isotropic in strongly magnetized regions than in weakly magnetized regions, especially on the nightside. These observations indicate that the anisotropy is a useful diagnostic of suprathermal electron transport, for which the conversion between the parallel and perpendicular momenta as required by the conservation of the first adiabatic invariant, along with the atmospheric absorption at low altitudes, are two crucial factors modulating the observed variation of the anisotropy. Our analysis also highlights the different roles on the observed anisotropy exerted by suprathermal electrons of different origins.

关键词： Mars ionosphere suprathermal electron pitch angle distribution

A Two-limb Explanation for the Optical-to-infrared Transmission Spectrum of the Hot Jupiter HAT-P-32Ab

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Research in Astronomy and Astrophysics 2023年第2期23卷 223-240页

作者：李馨凯陈果赵海斌王红池 CAS Key Laboratory of planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS center for excellence in comparative Planetology Hefei230026China CAS Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China

We present a new optical transmission spectrum of the hot Jupiter HAT-P-32Ab acquired with the Carnegie Observatories Spectrograph and Multiobject Imaging Camera(COSMIC) on the Palomar 200 inch Hale Telescope(P200).The P200/COSMIC transmission spectrum,covering a wavelength range of 3990–9390 A,is composed of 25 spectrophotometric bins with widths ranging from 200 to 400 A and consistent with previous transit measurements obtained in the common wavelength *** derive a combined optical transmission spectrum based on measurements from five independent instruments,which,along with the 1.1–1.7 μm spectrum acquired by the Hubble Space Telescope and two Spitzer measurements,exhibits an enhanced scattering slope blueward of a relatively flat optical continuum,a water absorption feature at 1.4 μm,and a carbon dioxide feature at 4.4 μ*** perform Bayesian spectral retrieval analyses on the 0.3–5.1 μm transmission spectrum and find that it can be well explained by a two-limb approximation of 134_(-33)^(+45)×solar metallicity,with a strongly hazy morning limb of 1134_(-194)^(+232) K and a haze-free evening limb of 1516_(-44)^(+33) *** makes HAT-P-32Ab a promising target for James Webb Space Telescope to look for asymmetric signatures directly in the light curves.

关键词： techniques spectroscopic-planets and satellites atmospheres-planets and satellites individual(HAT-P-32Ab)

Mineral chemistry and 3D tomography of a Chang’E 5 high-Ti basalt:implication for the lunar thermal evolution history

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Science Bulletin 2022年第7期67卷 755-761页

作者： Yun Jiang Ye Li Shiyong Liao Zongjun Yin Weibiao Hsu Key Laboratory of planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China center for excellence in comparative Planetology Chinese Academy of SciencesHefei 230026China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Paleontology&Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China

In December 2020, Chang’E-5(CE-5), China’s first lunar sample return mission, successfully collected samples totaling 1731 g from the northern Oceanus Procellarum. The landing site was located in a young mare plain, a great distance from those of Apollo and Luna missions. These young mare basalts bear critical scientific significance as they could shed light on the nature of the lunar interior(composition and structure) as well as the recent volcanism on the Moon. In this article, we investigated a CE-5 basalt sample(CE5 C0000 YJYX065) using a combination of state-of-art techniques, including high resolution X-ray tomographic microscopy(HR-XTM), energy dispersive X-ray spectroscopy(EDS)-based scanning electron microscope(SEM), and electron probe microanalysis(EPMA) to reveal its 3 D petrology and *** results show that this sample has a fine-to medium-grained subophitic texture, with sparse olivine phenocrysts setting in the groundmass of pyroxene, plagioclase, ilmenite and trace amounts of other phases. It has an extremely high ilmenite modal abundance(17.8 vol%) and contains a significant amount(0.5 vol%) of Ca-phosphate grains. The mineral chemistry is in excellent agreement with that of Apollo and Luna high-Ti basalts. The major phase pyroxenes also display strong chemical zoning with compositions following the trends observed in Apollo high-Ti basalts. Based on current data, we came to the conclusion that CE5 C0000 YJYX065 is a high-Ti mare basalt with a rare earth element(REE) enriched signature. This provides a rigid ground-truth for the geological context at the CE-5 landing site and clarifies the ambiguity inferred from remote sensing surveys.

关键词： Chang’E-5 High-Ti basalt Mare basalt High resolution X-ray tomographic microscopy(HR-XTM) Lunar return sample