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Confrontation between Quantized Periods of Some Extra-Solar Planetary Systems and Observations
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作者 A. B. Morcos 《International Journal of Astronomy and Astrophysics》 2013年第2期28-32,共5页
A simple formula, using the quantum numbers of solar system planets and some quantized extra-solar planets, to estimate the periods, is done. The quantum numbers, calculated by other authors, have been used to find th... A simple formula, using the quantum numbers of solar system planets and some quantized extra-solar planets, to estimate the periods, is done. The quantum numbers, calculated by other authors, have been used to find the orbital periods of solar system planets and some extra-solar planets. Observed periods have been used to compare them with the estimated periods from the given formula. It is found that the given relation is applicable perfectly for the solar system planets. Some extra-solar planets, of stars having approximately the same mass as the sun, are chosen to apply the same relation. The differences between the observed and calculated periods for the extra-solar systems have been calculated and tabulated. It is found that the percentage errors between the predicted values and the corresponding observed values for extra-planetary systems are controlled by the star’s mass and its quantum number. The percentage error decreases by increasing the quantum number, for quantum numbers over 4. When the quantum number is less than or equal 4, it is found that the percentage error decreases by decreasing the quantum number. 展开更多
关键词 Quantization PERIODS Extra-planetary extra-solar planet
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Correction:The escape mechanisms of the proto-atmosphere on terrestrial planets:“boil-off”escape,hydrodynamic escape and impact erosion
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作者 Ziqi Wang You Zhou Yun Liu 《Acta Geochimica》 EI CAS CSCD 2024年第3期623-623,共1页
In the original publication of the article,the affiliation“College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,People’s Republic of China”for author Ziqi Wang was missing and i... In the original publication of the article,the affiliation“College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,People’s Republic of China”for author Ziqi Wang was missing and included in this correction article. 展开更多
关键词 ESCAPE planet COLLEGE
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Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS
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作者 Jia-Qi Wang Xiao-Jun Jiang +18 位作者 Jie Zheng Hanna Kellermann Arno Riffeser Liang Wang Karen A.Collins Allyson Bieryla Lars A.Buchhave Steve B.Howell Elise Furlan Eric Girardin Joao Gregorio Eric Jensen Felipe Murgas Mesut Yilmaz Sam Quinn Xing Gao Ruo-Yu Zhou Frank Grupp Hui-Juan Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期129-143,共15页
We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 B.Exoplanet candidates... We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 B.Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium apertures.The analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Objects of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period targets.TOI-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric data.We measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041RJ and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(J) and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1). 展开更多
关键词 planets and satellites fundamental parameters-planets and satellites gaseous planets-stars fundamental parameters-stars low-mass-methods data analysis-techniques photometric-techniques spectroscopic
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Black Hole Singularities and Planetary Formation
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作者 Louise Riofrio 《Journal of Applied Mathematics and Physics》 2024年第4期1079-1088,共10页
The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift o... The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift observations from the James Webb Space Telescope reveal that distant galaxies and their central black holes formed shortly after the Big Bang. An innovation about the speed of light explains how supermassive black holes could have formed primordially. Predictions of Hawking radiation include the possibility of black holes contributing to the energy of stars such as the Sun. Black holes have also been suggested as a source of radiation and magnetic fields in giant planets. Observations of Enceladus raise the possibility that this moon and other objects near Saturn’s Rings contain small singularities. Extrapolations of this methodology indicate that black holes could exist within solar system bodies including planets. Extended discussion describes how their presence could explain mysteries of internal heat, planetary magnetic fields, and processes of solar system formation. 展开更多
关键词 Black Holes GALAXIES Magnetic Fields planets planetary Formation Speed of Light
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英国高中地理教材栏目设置的特点及启示——以Geography B Evolving Planet为例
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作者 徐波 安龙 +3 位作者 袁圆 欧然然 谢庆玲 冯婷 《咸阳师范学院学报》 2023年第4期84-88,共5页
以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问... 以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问题思考类栏目指向不同教学目标,技能训练类栏目凸显实用性和应用性的学科特色,信息提示类栏目关注学生心理特点,考试导向类栏目提高应试答题技巧。受此启发,未来我国中学地理教材栏目设置应有所侧重,即教材栏目在内容设置上要注重针对性,在形式设置上要增加多样性,在外观设置上要注重醒目性。 展开更多
关键词 地理教材 Geography B Evolving planet 教材栏目
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Relation between Mass and Radius of Exoplanets Distinguished by their Density
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作者 Alberto S.Betzler JoséG.V.Miranda 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期47-55,共9页
The formation of the solar system has been studied since the 18th century and received a boost in 1995 with the discovery of the first exoplanet,51 Pegasi b.The investigations increased the number of confirmed planets... The formation of the solar system has been studied since the 18th century and received a boost in 1995 with the discovery of the first exoplanet,51 Pegasi b.The investigations increased the number of confirmed planets to about5400 to date.The possible internal structure and composition of these planets can be inferred from the relationship between planet mass and radius,M-R.We have analyzed the M-R relation of a selected sample of iron-rock and ice-gas planets using a fractal approach to their densities.The application of fractal theory is particularly useful to define the physical meaning of the proportionality constant and the exponent in an empirical M-R power law in exoplanets,but this does not necessarily mean that they have an internal fractal structure.The M-R relations based on this sample are M=(1.46±0.08)R^(2.6±0.2)for the rocky population(3.6≤ρ≤14.3 g cm^(-3)),with 1.5≤M≤39M_(⊕),and M=(0.27±0.04)R^(2.7±0.2)for ice-gas planets(0.3≤ρ≤2.1 g cm^(-3))with 5.1≤M≤639 M_(⊕)(or■2 M_(J))and orbital periods greater than 10 days.Both M-R relations have in their density range a great predictive power for the determination of the mass of exoplanets and even for the largest icy moons of the solar system.The average fractal dimension of these planets is D=2.6±0.1,indicating that these objects likely have a similar degree of heterogeneity in their densities and a nearly similar composition in each sample.The M-R diagram shows a"gap"between ice-gas and iron-rock planets.This gap is a direct consequence of the density range of these two samples.We empirically propose an upper mass limit of about 100 M_(⊕),so that an M-R relation for ice-gas planets in a narrow density range is defined by M∝R^(3). 展开更多
关键词 planets and satellites:formation planets and satellites:terrestrial planets planets and satellites:gaseous planets
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A Linear Operator Method to Compute the Normal Modes with Rotation of any Asymmetric 3D Planet with Pure Vector Spherical Harmonics
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作者 Mian Zhang Cheng-Li Huang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期224-254,共31页
In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surfac... In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surface spherical harmonics(GSSHs) are usually applied to the elliptical models with a stress tensor, which cannot be expressed in vector spherical harmonics explicitly. However, GSSHs involve complicated math. LOM is an alternative to GSSHs,whereas it only deals with the coupling fields of the same azimuthal order m, as is the case when a planet model is axially symmetric and rotates about that symmetry axis. We extend LOM to any asymmetric 3D model. The lower degree spheroidal modes of the Earth are computed to validate our method, and the results agree very well with what is observed. We also compute the normal modes of a two-layer Saturn model as a simple application. 展开更多
关键词 planets and satellites:interiors Earth planets and satellites:gaseous planets
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The Perihelion Precession of the Planets Indicates a Variability of the Gravitational Constant
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作者 Hans Peter Weber 《Journal of Modern Physics》 CAS 2023年第5期670-675,共6页
The gravitational constant G according to the theory of NEWTON is the most imprecise constant of all physical constants. Moreover, there are a number of phenomena which suggest that this is caused by its invariant nat... The gravitational constant G according to the theory of NEWTON is the most imprecise constant of all physical constants. Moreover, there are a number of phenomena which suggest that this is caused by its invariant nature and the gravitation constant might be in fact a variable. In this article, a possible dependence of the gravitational constant on the distance between the two mass points is determined from the observed values of the perihelion displacement of the planets. However, to fit the observed measurements the 1/r<sup>2</sup> dependence is modified to a 1/r2+1/R</sup> dependence with “R” as the Rydberg constant. With the proposed new power function, the perihelion precessions of the planets are recalculated and then compared with previous observations as well as the postulated anomaly of Saturn. 展开更多
关键词 Gravitational Constant Perihelion Precession of the planets Gravitational Equation with Variable G
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近邻宜居行星巡天计划:利用空间天体测量法寻找下一个“地球” 被引量:1
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作者 季江徽 李海涛 +10 位作者 张俊波 李东 方亮 王素 邓雷 陈果 李飞 董瑶 李保权 高晓东 鲜浩 《空间科学学报》 CAS CSCD 北大核心 2024年第2期193-214,共22页
近邻宜居行星巡天计划(Closeby Habitable Exoplanet Survey,CHES)采用空间微角秒级别的高精度天体测量技术,普查太阳系近邻(10 pc内)约100颗FGK等类型恒星,探测宜居带类地行星或超级地球;详细普查宜居行星的数目、真实质量和三维轨道... 近邻宜居行星巡天计划(Closeby Habitable Exoplanet Survey,CHES)采用空间微角秒级别的高精度天体测量技术,普查太阳系近邻(10 pc内)约100颗FGK等类型恒星,探测宜居带类地行星或超级地球;详细普查宜居行星的数目、真实质量和三维轨道等信息,这将是国际上首次近邻宜居带类地行星的空间探测任务.CHES的有效载荷是一台口径为1.2 m,视场为0.44°×0.44°,焦距为36 m的高像质、低畸变、高稳定光学望远镜,采用同轴三反TMA光学成像系统.为实现宜居带类地行星探测,CHES任务中的测量精度为1μas,是目前国际测量精度最高的空间探测项目.在空间科学先导专项背景型号项目的支持下,CHES团队深入凝练和论证科学目标,成功突破了三项关键技术难题:实现了畸变大视场高像质空间望远镜光学系统技术的重要突破;突破了10–5 pixel级别星间距测量技术;实现了卫星系统高稳定度姿态控制精度及热控精度的创新.CHES预计发现50颗类地行星,引领中国空间科学探测技术的跨越式发展. 展开更多
关键词 高精度天体测量法 系外行星 近邻宜居行星
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天基分布式光学合成孔径技术 被引量:1
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作者 王小勇 张家福 +1 位作者 李凌 郭崇岭 《空间科学学报》 CAS CSCD 北大核心 2024年第2期356-367,共12页
宜居带行星探测研究是近年系外行星研究的热点领域之一,探测太阳系附近的宜居行星对研究生命起源等具有重要意义,成为系外行星探测的重要内容.天基分布式合成孔径技术作为系外宜居行星探测的重要手段,已经成为目前前沿光学技术研究的热... 宜居带行星探测研究是近年系外行星研究的热点领域之一,探测太阳系附近的宜居行星对研究生命起源等具有重要意义,成为系外行星探测的重要内容.天基分布式合成孔径技术作为系外宜居行星探测的重要手段,已经成为目前前沿光学技术研究的热点方向,但是仍有诸多技术问题需解决.本文从宜居行星搜寻计划的需求出发,根据以迈克尔逊干涉成像为基础的天基分布式合成孔径系统技术原理,介绍了国内外典型分布式合成孔径系统的技术发展,重点分析了实现天基分布式干涉成像所需采用的控制系统和技术,并阐述了解决高精度空间测距、高精度时间同步、多层级位相同步等关键问题的技术要点.为未来大型柔性可重构空间望远系统的建造提供了参考. 展开更多
关键词 宜居行星 分布式 合成孔径 干涉成像
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Guarding Our Blue Planet
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作者 ZHOU LIN 《China Today》 2023年第6期56-58,共3页
Chinese young people are gearing up for preserving the ocean and marine wildlife.IU Qian is a diving instructor and an ardent volunteer for marine environmental protection.He has been to many tourist attractions aroun... Chinese young people are gearing up for preserving the ocean and marine wildlife.IU Qian is a diving instructor and an ardent volunteer for marine environmental protection.He has been to many tourist attractions around the world,such as the Nile River in Africa and the Red Sea lying between Africa and Asia.He turned his passion into a career,devoting himself to exploring deeper waters and sharing his knowledge and skills with more people in preserving the blue planet. 展开更多
关键词 planet PRESERVING GUARD
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A Novel Explanation of the Origin of the Magnetic Field of Stars and Planets
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作者 Elie W’ishe Sorongane 《Open Journal of Applied Sciences》 2023年第8期1289-1300,共12页
Today, the origin of the magnetic field of stars and planets is explained by the dynamo effect. Since Cowling’s anti-dynamo theorem has forbidden a purely axisymmetric dynamo, scientists are all convinced today that ... Today, the origin of the magnetic field of stars and planets is explained by the dynamo effect. Since Cowling’s anti-dynamo theorem has forbidden a purely axisymmetric dynamo, scientists are all convinced today that the fluid flow in the core of a star cannot be laminar, so it is turbulent. However, we will see in this study that the configuration in which the conductive fluid contained in the core of a star is in rapid rotation around an axis of symmetry is the one that best explains the origin of the magnetic field of stars and planets. It also explains why certain types of stars have very intense magnetic fields. Indeed, we will show here that the magnetic field of stars and planets is created by the electric current generated by the rotational movement of charged fluid particles as in an electromagnet. The lines of this magnetic field are channelled by the solid paramagnetic seed which plays the role of magnetic core in the cores of planets and stars. The seed is composed mainly of Iron and Nickel on the planets and of solid helium-3 in the stars. In this work, we will use this model of rapidly rotating fluids to introduce a new way to ionize a neutral gas and maintain it in a plasma state for indefinitely large time scales, to present a new technique for generating very intense magnetic fields, to establish a new magnetic nucleation process and to propose a new type of nuclear fusion reactor in which the plasma is perpetually rapidly rotating. 展开更多
关键词 Magnetic Field STARS planets ELECTROMAGNET Fluid ROTATION Plasma
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Hubble WFC3 Spectroscopy of the Terrestrial Planets L 98–59c and d:No Evidence for a Clear Hydrogen Dominated Primary Atmosphere
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作者 Li Zhou Bo Ma +1 位作者 Yong-Hao Wang Yi-Nan Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第2期140-162,共23页
The nearby bright M-dwarf star L 98–59 has three terrestrial-sized planets.One challenge remaining in characterizing atmospheres around such planets is that it is not known a priori whether they possess any atmospher... The nearby bright M-dwarf star L 98–59 has three terrestrial-sized planets.One challenge remaining in characterizing atmospheres around such planets is that it is not known a priori whether they possess any atmospheres.Here we report on study of the atmospheres of L 98–59 c and L 98–59 d using near-infrared spectral data from the G141 grism of Hubble Space Telescope(HST)/Wide Field Camera 3.We can reject the hypothesis of a clear atmosphere dominated by hydrogen and helium at a confidence level of ~3σ for both planets.Thus they could have a primary hydrogen-dominated atmosphere with an opaque cloud layer,or could have lost their primary hydrogen-dominated atmosphere and re-established a secondary thin atmosphere,or have no atmosphere at all.We cannot distinguish between these scenarios for the two planets using the current HST data.Future observations with the James Webb Space Telescope would be capable of confirming the existence of atmospheres around L 98–59 c and d and determining their compositions. 展开更多
关键词 planets and satellites atmospheres-planets and satellites terrestrial planets-instrumentation spectrographs-planets and satellites individual(L 98-59 c L 98-59 d)
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基于One Planet Living框架的城市可持续发展规划——以新加坡滨海湾为例
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作者 何丰 《安徽建筑》 2023年第3期14-16,共3页
文章基于One Planet Living框架归纳分析了新加坡滨海湾在可持续发展方面实行的具体策略及措施,并重点对交通与出行、水资源可持续管理和健康与福祉三项原则详细研究,总结了滨海湾可持续发展规划的成功经验,以期为我国城市可持续发展提... 文章基于One Planet Living框架归纳分析了新加坡滨海湾在可持续发展方面实行的具体策略及措施,并重点对交通与出行、水资源可持续管理和健康与福祉三项原则详细研究,总结了滨海湾可持续发展规划的成功经验,以期为我国城市可持续发展提供借鉴和新思路。 展开更多
关键词 滨海湾 可持续发展 One planet Living
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行星紫外光谱探测载荷技术发展综述
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作者 余俊 杜洋 +4 位作者 张嵬 余越 齐润泽 王伟 王占山 《上海航天(中英文)》 CSCD 2024年第5期79-89,共11页
行星大气是深空探测、空间天文等领域的重要研究方向,其中紫外谱段是行星大气活动研究中重要的环节。为了获得不同地外行星的紫外光谱信息,国际研究团队近几十年来开展了相关技术研究,并研制了大量科学探测载荷。本文主要综述了行星紫... 行星大气是深空探测、空间天文等领域的重要研究方向,其中紫外谱段是行星大气活动研究中重要的环节。为了获得不同地外行星的紫外光谱信息,国际研究团队近几十年来开展了相关技术研究,并研制了大量科学探测载荷。本文主要综述了行星紫外光谱探测载荷的发展,并分析了紫外核心器件技术发展推进下的紫外光谱载荷技术的发展与迭代,最后给出了我国在行星紫外光谱探测领域可能的发展方向和重点研究方向。 展开更多
关键词 行星 紫外 空间探测 光谱仪
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激励频率对换挡行星传动系统非线性动力学影响分析
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作者 伍晓龙 杜垚森 +1 位作者 高鹏举 王晓赛 《机械传动》 北大核心 2024年第3期27-34,共8页
换挡机构是变速系统中最关键的部件之一,其性能直接影响传动系统的动力性和平稳性。建立了二级换挡行星传动系统动力学方程,研究了外界激励频率对传动系统复杂动力学特性的影响;通过分析分岔图、时域响应图、相图、庞加莱截面图以及频... 换挡机构是变速系统中最关键的部件之一,其性能直接影响传动系统的动力性和平稳性。建立了二级换挡行星传动系统动力学方程,研究了外界激励频率对传动系统复杂动力学特性的影响;通过分析分岔图、时域响应图、相图、庞加莱截面图以及频谱图变化规律,明晰了二级换挡行星传动系统混沌振动特性,获得了外界激励频率稳定振动区间;利用比例微分控制方法对传动系统混沌振动进行控制,将混沌振动调整为稳定的单周期振动。研究结果为提高换挡行星传动系统运转的稳定性奠定了基础。 展开更多
关键词 换挡机构 行星齿轮 混沌振动 混沌控制
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弱引力环境四足机器人的强化学习姿态机动控制
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作者 高海波 齐骥 +3 位作者 苏桓立 霍明英 于海涛 邓宗全 《宇航学报》 EI CAS CSCD 北大核心 2024年第10期1676-1684,共9页
针对四足机器人在小天体表面跳跃巡游探测过程中的空中姿态控制问题,提出了一种基于强化学习的无模型控制方案。在小天体的弱引力环境下,机器人单次跳跃的滞空时间很长,机器人需要利用这段时间修正起跳带来的姿态偏差以实现安全着陆,或... 针对四足机器人在小天体表面跳跃巡游探测过程中的空中姿态控制问题,提出了一种基于强化学习的无模型控制方案。在小天体的弱引力环境下,机器人单次跳跃的滞空时间很长,机器人需要利用这段时间修正起跳带来的姿态偏差以实现安全着陆,或改变偏航角以改变未来行进方向。提出的基于近端策略优化(PPO)算法训练的控制器以猫落反射为启发,无需引入额外的姿态控制执行器。仿真结果表明,训练得到的控制器可通过控制四足机器人摆动腿部关节实现三轴姿态机动。设计并搭建了四足机器人气浮微重力模拟试验平台,通过样机试验,控制策略模型的有效性得到了验证。 展开更多
关键词 星球探测机器人 小天体探测 强化学习 微低重力模拟
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天语计划——寻找第二个太阳系及探索动态宇宙
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作者 冯发波 芮易成 +32 位作者 杜芝茂 林清 张聪聪 周丹 崔开明 OGIHARA Masahiro 杨明 林杰 蔡永志 杨涛只 庞晓莹 简明杰 李文雄 郭恒潇 史弦 史建春 李荐扬 郭康柔 姚嵩 陈啊明 贾鹏 谭先瑜 JENKINS S.James 蒋宏轩 张铭缘 李可欣 肖光耀 郑书玥 宣一帆 郑捷 何敏 JONES R.A.Hugh 宋翠英 《天文学报》 CAS CSCD 北大核心 2024年第4期1-43,共43页
像木星和土星这样的冷巨行星对类地行星的形成和宜居性起到了关键作用,因此,对像太阳系这样具有多个冷巨行星的系统的搜寻具有重要意义.Kepler以及TESS (Transiting Exoplanet Survey Satellite)太空望远镜成功地通过凌星的方法发现了... 像木星和土星这样的冷巨行星对类地行星的形成和宜居性起到了关键作用,因此,对像太阳系这样具有多个冷巨行星的系统的搜寻具有重要意义.Kepler以及TESS (Transiting Exoplanet Survey Satellite)太空望远镜成功地通过凌星的方法发现了大量短周期行星,然而这些巡天项目的观测基线不足以发现更长周期的行星.为此,天语计划将部署两台1m望远镜(天语一号和天语二号),用于结合天语和其他计划的数据通过凌星法来发现冷巨行星及其他行星,并最终发现类太阳系.天语一号具有约10平方度的视场以及高速CMOS (complementary metal-oxide-semiconductor)科学相机,将对超过1000万颗恒星每小时进行一次高精度测光采样,并通过天语二号的多波段测光、光谱仪以及高分辨率成像对天语一号发现的候选行星进行确认.天语望远镜将放置于海拔约4000m的中国青海冷湖,是目前中国境内最好观测台址之一.天语对亮于14等星的测光精度为0.1%,对亮于18等星的测光精度优于1%,天语预计在5yr内将在类太阳周期发现超过300颗凌星行星,其中包括约17颗冷巨行星.基于系统轨道共面以及孪生地球发生率为10%的假设,天语预计将发现1-2个类太阳系,并可被未来的地球2.0计划所证实.此外,天语还将通过多种巡天观测模式测量从亚秒到周时标的光变,探测不同时标的时域现象,包括超新星早期光变、稀有变星和双星、潮汐瓦解事件、Be星、彗星活动以及系外小行星等.这些发现不仅将深化我们对宇宙的理解,还将为公众科学和科普提供重要平台. 展开更多
关键词 技术:测光 行星与卫星:探测 行星与卫星:形成 恒星:超新星:普通 星:变星:普通 小行星:普通 恒星:伽马 射线暴:普通
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基于CHES卫星的模拟观测与轨道反演
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作者 暴春晖 季江徽 +6 位作者 谭东杰 晋升 黄秀敏 王素 陈果 董瑶 刘佳成 《天文学报》 CAS CSCD 北大核心 2024年第4期99-112,共14页
迄今为止,视向速度法与凌星法发现了绝大多数系外行星,天体测量法与之相比在行星轨道参数和质量确定等方面具有独特优势.近邻宜居行星巡天计划(Closeby Habitable Exoplanet Survey,CHES)拟基于微角秒级空间天体测量方法搜寻太阳系近邻... 迄今为止,视向速度法与凌星法发现了绝大多数系外行星,天体测量法与之相比在行星轨道参数和质量确定等方面具有独特优势.近邻宜居行星巡天计划(Closeby Habitable Exoplanet Survey,CHES)拟基于微角秒级空间天体测量方法搜寻太阳系近邻(距离太阳约10 pc)的100颗类太阳型恒星周围的宜居带类地行星;开展近邻行星系统的全面普查,获取行星真实质量和三维轨道参数,建立完备的近邻系外行星数据库.基于CHES卫星的观测模式与科学目标,针对Alpha Centauri A、模拟太阳系系统、51 Peg与黑洞Cyg X-1进行了模拟观测,生成了天体测量仿真数据,使用Lomb-Scargle与贝叶斯信息准则(Bayesian information criteria,BIC)两种周期谱分析行星轨道周期信号,并采用Markov Chain Monte Carlo(MCMC)算法对行星系统进行轨道反演,获得的结果与行星初始参数吻合.进一步讨论了参考星周围存在的巨行星对于宜居行星探测的影响,利用BIC周期谱方法可识别周围可能存在行星的参考星. 展开更多
关键词 天体测量学 行星与卫星:探测 类地行星 方法:数值
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基于半球形瞬时撞击坑的近地天体撞击诱发海啸的深水波模型
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作者 李妙蕾 史建春 +4 位作者 马月华 张瑞利 赵海斌 唐梦辉 杨大陶 《天文学报》 CAS CSCD 北大核心 2024年第5期110-120,共11页
采用初始扰动为半球形瞬时撞击坑作为初始条件,建立了近地天体撞击诱发海啸的深水波模型,应用到特定情形下(小行星直径为140 m、撞击速度与密度采用车里雅宾斯克陨击参数、撞击区域平均海洋深度采用太平洋平均水深4 km)研究了近地天体... 采用初始扰动为半球形瞬时撞击坑作为初始条件,建立了近地天体撞击诱发海啸的深水波模型,应用到特定情形下(小行星直径为140 m、撞击速度与密度采用车里雅宾斯克陨击参数、撞击区域平均海洋深度采用太平洋平均水深4 km)研究了近地天体撞击海洋诱发海啸的波高最大值随距离和时间的演化情况.对比不同的瞬时撞击坑模型和传播模型对海啸波高的影响发现:半球形瞬时撞击坑诱发的海啸危害比抛物形瞬时撞击坑更大;相对于深水波模型,浅水波模型给出撞击诱发海啸的规模较大;对于中等尺寸(直径在几百米范围内)的小行星,研究其撞击海洋诱发海啸,更适合采用瞬时撞击坑形状为半球形的深水波模型. 展开更多
关键词 小行星:普通 地球 流体力学 方法:解析
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