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Everything Is a Circle: A New Universal Orbital Model
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作者 Asli Pinar Tan 《Advances in Aerospace Science and Technology》 2024年第3期94-116,共23页
Based on measured astronomical position data of heavenly objects in the Solar System and other planetary systems, all bodies in space seem to move in some kind of elliptical motion with respect to each other. Accordin... Based on measured astronomical position data of heavenly objects in the Solar System and other planetary systems, all bodies in space seem to move in some kind of elliptical motion with respect to each other. According to Kepler’s 1st Law, “orbit of a planet with respect to the Sun is an ellipse, with the Sun at one of the two foci.” Orbit of the Moon with respect to Earth is also distinctly elliptical, but this ellipse has a varying eccentricity as the Moon comes closer to and goes farther away from the Earth in a harmonic style along a full cycle of this ellipse. In this paper, our research results are summarized, where it is first mathematically shown that the “distance between points around any two different circles in three-dimensional space” is equivalent to the “distance of points around a vector ellipse to another fixed or moving point, as in two-dimensional space”. What is done is equivalent to showing that bodies moving on two different circular orbits in space vector-wise behave as if moving on an elliptical path with respect to each other, and virtually seeing each other as positioned at an instantaneously stationary point in space on their relative ecliptic plane, whether they are moving with the same angular velocity, or different but fixed angular velocities, or even with different and changing angular velocities with respect to their own centers of revolution. This mathematical revelation has the potential to lead to far reaching discoveries in physics, enabling more insight into forces of nature, with a formulation of a new fundamental model regarding the motions of bodies in the Universe, including the Sun, Planets, and Satellites in the Solar System and elsewhere, as well as at particle and subatomic level. Based on the demonstrated mathematical analysis, as they exhibit almost fixed elliptic orbits relative to one another over time, the assertion is made that the Sun, the Earth, and the Moon must each be revolving in their individual circular orbits of revolution in space. With this expectation, individual orbital parameters of the Sun, the Earth, and the Moon are calculated based on observed Earth to Sun and Earth to Moon distance data, also using analytical methods developed as part of this research to an approximation. This calculation and analysis process have revealed additional results aligned with observation, and this also supports our assertion that the Sun, the Earth, and the Moon must actually be revolving in individual circular orbits. 展开更多
关键词 Solar System Planetary System PLANET Satellite Earth MOON Topology Circle Sun ELLIPSE ORBIT TRAJECTORY orbital mechanics
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Averaging analyses for spacecraft orbital motions around asteroids
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作者 Wei-Duo Hu D.J.Scheeres 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第3期294-300,共7页
This paper summarizes a few cases of spacecraft orbital motion around asteroid for which averaging method can be applied, i.e., when central body rotates slowly, fast, and when a spacecraft is near to the resonant orb... This paper summarizes a few cases of spacecraft orbital motion around asteroid for which averaging method can be applied, i.e., when central body rotates slowly, fast, and when a spacecraft is near to the resonant orbits between the spacecraft mean motion and the central body's rotation. Averaging conditions for these cases are given. As a major extension, a few classes of near resonant orbits are analyzed by the averaging method. Then some resulted conclusions of these averaging analyses are applied to understand the stabil- ity regions in a numerical experiment. Some stability conclu- sions are obtained. As a typical example, it is shown in detail that near circular 1 : 2 resonant orbit is always unstable. 展开更多
关键词 orbital mechanics ASTEROID Secular motion Resonant orbit Averaging theory
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A Study on the Relationship between the Orbital Lifetime and Inclination of Low Lunar Satellites
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作者 Hai-Hong Wang Lin Liu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第6期665-670,共6页
A detailed theoretical analysis on the orbital lifetime and orbital inclination of a Low Moon-Orbiting satellite (LMOs) and the ‘stable areas' of long orbital lifetime are given. Numerical simulations under the re... A detailed theoretical analysis on the orbital lifetime and orbital inclination of a Low Moon-Orbiting satellite (LMOs) and the ‘stable areas' of long orbital lifetime are given. Numerical simulations under the real force model were carried out, which not only validate the theoretical analysis and also give some valuable results for the orbit design of the LMOs. 展开更多
关键词 celestial mechanics - Low-Moon-Orbiting satellite orbital lifetime
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Periodic Orbits in Rotating Second Degree and Order Gravity Fields 被引量:3
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作者 Wei-Duo Hu Daniel J. Scheeres 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第1期108-118,共11页
Periodic orbits in an arbitrary 2nd degree and order uniformly rotating gravity field are studied. We investigate the four equilibrium points in this gravity field. We see that close relation exists between the stabil... Periodic orbits in an arbitrary 2nd degree and order uniformly rotating gravity field are studied. We investigate the four equilibrium points in this gravity field. We see that close relation exists between the stability of these equilibria and the existence and stability of their nearby periodic orbits. We check the periodic orbits with non-zero periods. In our searching procedure for these periodic orbits, we remove the two unity eigenvalues from the state transition matrix to find a robust, non-singular linear map to solve for the periodic orbits. The algorithm converges well, especially for stable periodic orbits. Using the searching procedure, which is relatively automatic, we find five basic families of periodic orbits in the rotating second degree and order gravity field for planar motion, and discuss their existence and stability at different central body rotation rates. 展开更多
关键词 celestial / orbital mechanics - asteroid - periodic orbit - resonance
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Solution set on the natural satellite formation orbits under first-order earth's non-spherical perturbation 被引量:1
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作者 Humei Wang Wei Yang Junfeng Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期503-510,共8页
Using the reference orbital element approach, the precise governing equations for the relative motion of formation flight are formulated. A number of ideal formations with respect to an elliptic orbit can be designed ... Using the reference orbital element approach, the precise governing equations for the relative motion of formation flight are formulated. A number of ideal formations with respect to an elliptic orbit can be designed based on the relative motion analysis from the equations. The features of the oscillating reference orbital elements are studied by using the perturbation theory. The changes in the relative orbit under perturbation are divided into three categories, termed scale enlargement, drift and distortion respectively. By properly choosing the initial mean orbital elements for the leader and follower satellites, the deviations from originally regular formation orbit caused by the perturbation can be suppressed. Thereby the natural formation is set up. It behaves either like non-disturbed or need little control to maintain. The presented reference orbital element approach highlights the kinematics properties of the relative motion and is convenient to incorporate the results of perturbation analysis on orbital elements. This method of formation design has advantages over other methods in seeking natural formation and in initializing formation. 展开更多
关键词 orbital mechanics . Satellite formation flight .orbital elements . Reference orbital elements . Perturbation
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Predicting Rate Constants for Nucleophilic Reactions of Amines with Diarylcarbenium Ions Using an ONIOM Method
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作者 张志平 王晨 +1 位作者 傅尧 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第6期669-674,745,共7页
The rate constants of the nucleophilic reactions between amines and benzhydrylium ions were calculated using first-principles theoretical methods. Solvation models including PCM, CPCM, and COSMORS, as well as differen... The rate constants of the nucleophilic reactions between amines and benzhydrylium ions were calculated using first-principles theoretical methods. Solvation models including PCM, CPCM, and COSMORS, as well as different types of atomic radii including UA0, UAKS, UAHF, Bondi, and UFF, and several single-point energy calculation methods (B3LYP, B3P86, B3PW91, BHANDH, PBEPBE, BMK, M06, MP2, and ONIOM method) were examined. By comparing the correlation between experimental rate constants and the calculated values, the ONIOM(CCSD(T)/6-311++G(2df,2p):B3LYP/6-311++G(2df,2p))//B3LYP/6- 31G(d)/PCM/UFF) method was found to perform the best. This method was then employed to calculate the rate constants of the reactions between diverse amines and diarylcarbenium ions. The calculated rate constants for 65 reactions of amines with diarylcarbenium ions are in agreement with the experimental values, indicating that it is feasible to predict the rate constant of a reaction between an amine and a diarylcarbenium ion through ab initio calculation. 展开更多
关键词 AMINE Diarylcarbenium ion Nucleophilic reaction Rate constant N-layered integrated molecule orbit and molecule mechanics
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Orbit Determination Using Satellite-to-Satellite Tracking Data 被引量:9
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作者 Ying-ChunLiu LinLiu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第3期281-286,共6页
Satellite-to-Satellite tricking (SST) data can be used to determine the orbits of spacecraft in two ways. One is combined orbit determination, which combines SST data with ground-based tracking data and exploits the ... Satellite-to-Satellite tricking (SST) data can be used to determine the orbits of spacecraft in two ways. One is combined orbit determination, which combines SST data with ground-based tracking data and exploits the enhanced tracking geometry. The other is the autonomous orbit determination, which uses only SST. The latter only fits some particular circumstances since it suffers the rank defect problem in other circumstances. The proof of this statement is presented. The nature of the problem is also investigated in order to find an effective solution. Several. methods of solution are discussed. The feasibility of the methods is demonstrated by their application to a simulation. 展开更多
关键词 Celestial mechanics: orbit determination - Methods: miscellaneous
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The Erosion Effect of Kapton Film in a Ground-based Atomic Oxygen Irradiation Simulator 被引量:4
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作者 王海斗 MA Guozheng +3 位作者 XU Binshi XING Zhiguo LI Guolu ZHANG Sen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1277-1282,共6页
In order to investigate the effect of space environmental factors on spacecraft materials, a ground-based simulation facility for space atomic oxygen(AO) irradiation was developed in our laboratory. Some Kapton film... In order to investigate the effect of space environmental factors on spacecraft materials, a ground-based simulation facility for space atomic oxygen(AO) irradiation was developed in our laboratory. Some Kapton film samples were subjected to AO beam generated by this facility. The Kapton films before and after AO exposure were analyzed comparatively using optical microscopy, scanning electronic microscopy, atomic force microscopy, high-precision microbalance, and X-ray photoelectron spectroscopy. The experimental results indicate that the transmittance of Kapton film will be reduced by AO irradiation notably, and its color deepens from pale yellow to brown. Surface roughness of the AO-treated sample is already increased obviously after AO irradiation for 5 hours, and exhibits a flannel-like appearance after 15 hours’ exposure in AO beam. The imide rings and benzene rings in kapton molecule are partially decomposed, and some new bonds form during AO irradiation. The mass loss of kapton film increases linearly with the increase of AO fluence, which is resulted from the formation of volatile products, such as CO, CO2 and NOx. The breakage in structure and degradation in properties of AO-treated Kapton film can be attributed to the integrated effect ofimpaction and oxidization of AO beam. The test results agree well with the space flight experimental data. 展开更多
关键词 space environment simulation low earth orbit atomic oxygen Kapton film erosion mechanism
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THEORETICAL ANALYSIS OF HYDROGENATION MECHANISM CATALYZED BY Pd-Fe_2O_3/D_(3520)
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作者 胡卫兵 张胜民 张曼征 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第4期35-38,共4页
The mechanism of catalytic hydrogenation of styrene is analyzed by catalysis theory and frontier molecular orbital theory.
关键词 olefinic double bonds hydrogenation mechanism frontier molecular orbital theory
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Satellite-station time synchronization information based real-time orbit error monitoring and correction of navigation satellite in Beidou System 被引量:4
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作者 HE Feng ZHOU ShanShi +5 位作者 HU XiaoGong ZHOU JianHua LIU Li GUO Rui LI XiaoJie WU Shan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第7期1395-1403,共9页
Satellite-station two-way time comparison is a typical design in Beidou System(BDS)which is significantly different from other satellite navigation systems.As a type of two-way time comparison method,BDS time synchron... Satellite-station two-way time comparison is a typical design in Beidou System(BDS)which is significantly different from other satellite navigation systems.As a type of two-way time comparison method,BDS time synchronization is hardly influenced by satellite orbit error,atmosphere delay,tracking station coordinate error and measurement model error.Meanwhile,single-way time comparison can be realized through the method of Multi-satellite Precision Orbit Determination(MPOD)with pseudo-range and carrier phase of monitor receiver.It is proved in the constellation of 3GEO/2IGSO that the radial orbit error can be reflected in the difference between two-way time comparison and single-way time comparison,and that may lead to a substitute for orbit evaluation by SLR.In this article,the relation between orbit error and difference of two-way and single-way time comparison is illustrated based on the whole constellation of BDS.Considering the all-weather and real-time operation mode of two-way time comparison,the orbit error could be quantifiably monitored in a real-time mode through comparing two-way and single-way time synchronization.In addition,the orbit error can be predicted and corrected in a short time based on its periodic characteristic.It is described in the experiments of GEO and IGSO that the prediction accuracy of space signal can be obviously improved when the prediction orbit error is sent to the users through navigation message,and then the UERE including terminal error can be reduced from 0.1 m to 0.4 m while the average accuracy can be improved more than 27%.Though it is still hard to make accuracy improvement for Precision Orbit Determination(POD)and orbit prediction because of the confined tracking net and the difficulties in dynamic model optimization,in this paper,a practical method for orbit accuracy improvement is proposed based on two-way time comparison which can result in the reflection of orbit error. 展开更多
关键词 satellite navigation orbital mechanics time synchronization ephemeris fitting
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