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Electromagnetic Field Created by Rotation of Celestial Bodies 被引量:1
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作者 Arkady Dolginov 《Journal of Modern Physics》 2016年第16期2418-2425,共8页
The observed correlation of the angular momenta L<sup>ik</sup> and magnetic moments μ<sub>lm</sub> of celestial bodies (the Sun, planets and stars) was discussed by many au... The observed correlation of the angular momenta L<sup>ik</sup> and magnetic moments μ<sub>lm</sub> of celestial bodies (the Sun, planets and stars) was discussed by many authors but without any explanation. In this paper, a possible explanation of this phenomenon is suggested. It is shown that the function  satisfies Maxwell equations and can be considered as a function which determines the electro-magnetic properties of rotating heavy bodies. The R<sub>iklm</sub> is the Riemann tensor, which determines the gravitational field of the body, r<sub>g</sub> is the gravitational radius of the body, and η is the constant which has to be determined by observations. The field Φ<sub>lm</sub> describes the observed  correlation. It explains the stability of magnetic field of white dwarfs and neutron stars despite the ohmic dissipation. The function Φ<sub>l0</sub><sub></sub> describes the electric field created by rotating heavy bodies. The presented theory does not contradict any existed experiments and observations. 展开更多
关键词 Electromagnetic Field Rotating celestial Bodies GRAVITATION
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Quaternion methods and models of regular celestial mechanics and astrodynamics
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作者 Y.N.CHELNOKOV 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第1期21-80,共60页
This paper is a review,which focuses on our work,while including an analysis of many works of other researchers in the field of quaternionic regularization.The regular quaternion models of celestial mechanics and astr... This paper is a review,which focuses on our work,while including an analysis of many works of other researchers in the field of quaternionic regularization.The regular quaternion models of celestial mechanics and astrodynamics in the Kustaanheimo-Stiefel(KS)variables and Euler(Rodrigues-Hamilton)parameters are analyzed.These models are derived by the quaternion methods of mechanics and are based on the differential equations of the perturbed spatial two-body problem and the perturbed spatial central motion of a point particle.This paper also covers some applications of these models.Stiefel and Scheifele are known to have doubted that quaternions and quaternion matrices can be used efficiently to regularize the equations of celestial mechanics.However,the author of this paper and other researchers refuted this point of view and showed that the quaternion approach actually leads to efficient solutions for regularizing the equations of celestial mechanics and astrodynamics.This paper presents convenient geometric and kinematic interpretations of the KS transformation and the KS bilinear relation proposed by the present author.More general(compared with the KS equations)quaternion regular equations of the perturbed spatial two-body problem in the KS variables are presented.These equations are derived with the assumption that the KS bilinear relation was not satisfied.The main stages of the quaternion theory of regularizing the vector differential equation of the perturbed central motion of a point particle are presented,together with regular equations in the KS variables and Euler parameters,derived by the aforementioned theory.We also present the derivation of regular quaternion equations of the perturbed spatial two-body problem in the Levi-Civita variables and the Euler parameters,developed by the ideal rectangular Hansen coordinates and the orientation quaternion of the ideal coordinate frame.This paper also gives new results using quaternionic methods in the perturbed spatial restricted three-body problem. 展开更多
关键词 celestial mechanics ASTRODYNAMICS perturbed spatial two-body problem central motion REGULARIZATION Levi-Civita and Kustaanheimo-Stiefel(KS)variables Euler parameter QUATERNION
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A New Celestial Mechanics Dynamics of Accelerated Systems
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作者 Gabriel Barceló 《Journal of Applied Mathematics and Physics》 2019年第8期1732-1754,共23页
We present in this text the research carried out on the dynamic behavior of non-inertial systems, proposing new keys to better understand the mechanics of the universe. Applying the field theory to the dynamic magnitu... We present in this text the research carried out on the dynamic behavior of non-inertial systems, proposing new keys to better understand the mechanics of the universe. Applying the field theory to the dynamic magnitudes circumscribed to a body, our research has achieved a new conception of the coupling of these magnitudes, to better understand the behavior of solid rigid bodies, when subjected to multiple simultaneous, non-coaxial rotations. The results of the research are consistent with Einstein’s theories on rotation;however, we propose a different mechanics and complementary to classical mechanics, specifically for systems accelerated by rotations. These new concepts define the Theory of Dynamic Interactions (TDI), a new dynamic model for non-inertial systems with axial symmetry, which is based on the principles of conservation of measurable quantities: the notion of quantity, total mass and total energy. This theory deduces a general equation of motion for bodies endowed with angular momentum, when they are subjected to successive non-coaxial torques. 展开更多
关键词 MECHANICS DYNAMIC INTERACTIONS Non-Inertial SYSTEMS DYNAMIC Coupling celestial MECHANICS
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Giorgio Vasari’s Celestial Utopia of Whimsy and Joy:Constellations,Zodiac Signs,and Grotesques
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作者 Liana De Girolami Cheney 《Cultural and Religious Studies》 2019年第3期111-141,共31页
This study elaborates on the decoration of the ceiling in the refectory of the former Monteoliveto monastery in Naples,today part of the church of Sant’Anna dei Lombardi.It consists of three parts:an explanation of t... This study elaborates on the decoration of the ceiling in the refectory of the former Monteoliveto monastery in Naples,today part of the church of Sant’Anna dei Lombardi.It consists of three parts:an explanation of the ceiling design with its geometrical configurations of circles,octagons,hexagons,ovals,and squares;an iconographical analysis solely focusing on the ceiling decoration,which consists of grotesques,constellations,and zodiac signs;and a discussion of some of the literary and visual sources employed in the decoration.The Florentine Mannerist painter Giorgio Vasari,aided by several assistants,renovated and painted the ceilings between 1544 and 1545.Don Giammateo d’Anversa,the Abbot General of the Monteolivetan Order in Naples,composed the iconographical program with the assistance of insightful suggestions from the Florentine Monteolivetan prior Don Miniato Pitti,who was Vasari’s patron and friend as well.This oversight inspired Vasari to paint a celestial utopia of hilarity and whimsicality on the Neapolitan ceiling,thus leavening the other imagery,which combined both religious and secular representations of moral virtues and divine laws. 展开更多
关键词 CONSTELLATIONS zodiac signs GROTESQUES NEOPLATONISM harmony of the spheres refectory geometrical configurations celestial utopia whimsicality and laughter
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Notes on the Motion of Celestial Bodies
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作者 Gianni Donati 《Journal of Applied Mathematics and Physics》 2020年第12期2757-2774,共18页
A novel method for the computation of the motion of multi-body systems is proposed against the traditional one, based on the dynamic exchange of attraction forces or using complex field equations, that hardly face two... A novel method for the computation of the motion of multi-body systems is proposed against the traditional one, based on the dynamic exchange of attraction forces or using complex field equations, that hardly face two-body problems. The Newton gravitational model is interpreted as the emission of neutrino/gravitons from celestial bodies that combine to yield a cumulative flux that interacts with single bodies through a momentum balance. The neutrino was first found by Fermi to justify the energy conservation in <i><span style="white-space:nowrap;">&#946;</span></i> decay and, using his model;we found that the emission of neutrino from matter is almost constant independently from the nuclides involved. This flux can be correlated to Gauss constant G, allowing the rebuilding of Newton law on the basis of nuclear data, the neutrino weight and the speed of light. Similarly to nature, we can therefore separate in the calculations the neutrino flux, that represents the gravitational field, is dependent on masses and is not bound to the number of bodies involved, from the motion of each body that, given the field, is independent of the mass of bodies themselves. The conflict between exchanges of forces is avoided, the mathematics is simplified, the computational time is reduced to seconds and the stability of result is guaranteed. The example of computation of the solar system including the Sun and eight planets over a period of one to one hundred years is reported, together with the evolution of the shape of the orbits. 展开更多
关键词 ASTROPHYSICS celestial Mechanics Nuclear Physics Particle Physics GRAVITY Grand Unified Theory
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Proposal of New Criteria for Celestial Mechanics
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作者 Gabriel Barceló 《International Journal of Astronomy and Astrophysics》 2013年第4期385-391,共7页
Based on a new interpretation on the behavior of rigid bodies exposed to simultaneous non-coaxial rotations, we have developed a hypothesis: the Theory of Dynamics Interactions, which can be applied to understand cele... Based on a new interpretation on the behavior of rigid bodies exposed to simultaneous non-coaxial rotations, we have developed a hypothesis: the Theory of Dynamics Interactions, which can be applied to understand celestial mechanics. We have analyzed the velocity and acceleration fields generated in a rigid body with intrinsic angular momentum, when exposed to successive torques, to assess new criteria for this speeds coupling. In this context, reactions and inertial fields take place, which cannot be justified by means of classical mechanics. We believe that the results obtained after the analysis of dynamics fields systems accelerated by rotation will allow us to conceive a new perspective in celestial dynamics, astrometry, stellar dynamics and galactic astronomy, unknown up to date. After carrying out ample research, we have come to the conclusion that there still exists an unstructured scientific area under the present general assumptions and, more specifically, in the area of dynamic systems submitted to rotational accelerations. The aim of this paper is to present information of the surprising results obtained, and to attract the interest towards the investigation of this new area of knowledge in rotational non-inertial dynamics, and its multiple and remarkable scientific applications. 展开更多
关键词 celestial MECHANICS ASTRODYNAMICS Stellar DYNAMICS GALACTIC Astronomy ASTROMETRY DYNAMICS Fields Dynamical Systems Theory Orbital MECHANICS Intrinsic Angular Momentum SPEEDS Coupling
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A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques
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作者 Shi-Hai Yang Bo Xu Xin Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期245-264,共20页
As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5)... As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is proposed.However, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission. 展开更多
关键词 minor planets asteroids:general celestial mechanics Planetary Systems
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Time Dilation Cosmology 2
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第4期448-461,共14页
This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conu... This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conundrums in astrophysics, and ties astrophysics directly to quantum physics. It begins with a brief summary of the TDC model and contains the new derivation for the time dilation version of the formula for summing relativistic velocities, Einstein’s gravitational constant and the time dilation versions for the Lorentz factor and the Euclidean norm of the 3d velocity vector, the two of which can then be used in the Four-velocity formula. It is demonstrated how orbital curvature is manifested as the resultant of two time dilation-manifested velocities. It also explains why an interferometer cannot distinguish free fall from zero gravity and further elaborates on the author’s previous explanations of how spiral galaxies are formed, and contains mathematical proof that Black Holes are actually Magnetospheric Eternally Collapsing Objects (MECOs) that are massless spacetime vortices. 展开更多
关键词 GRAVITATION Time Time Dilation celestial Mechanics ISM: Kinematics and Dynamics Cosmology: Theory Galaxies: Evolution
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Effect of Orbital Characteristic of Inclined Third-body on Motion of Secondary-body for a Hierarchical Triple Systems
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作者 Majid Bakhtiari 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期1-11,共11页
The influence of a third-body's orbital elements on the second-body's motion in a hierarchical triple system is a crucial problem in astrophysics.Most prolonged evaluation studies have focused on a distant zer... The influence of a third-body's orbital elements on the second-body's motion in a hierarchical triple system is a crucial problem in astrophysics.Most prolonged evaluation studies have focused on a distant zero-inclined thirdbody.This study presents a new perspective on second-body motion equations that addresses a perturbing-body in an elliptic orbit derived with consideration of the axial-tilt(obliquity)of the primary.The proposed model is compared by the dual-averaged method and the N-body problem algorithm.After validation,a generalized threebody model is derived to investigate the effects of the third-body's orbital elements on secondary-body motion behavior.The proposed model considers short-time oscillations that affect secular evaluation and applies to exoplanets with all the primary and third body eccentricities,inclinations,and mass ratios.It is shown that the obliquity of the primary(or third-body's inclination)must be considered for precise long-term assessment,even in highly-hierarchical systems. 展开更多
关键词 celestial mechanics planets and satellites:dynamical evolution and stability Planetary Systems GRAVITATION
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Analytical Study of the Co-orbital Motion in the Circular Restricted Three-body Problem
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作者 Xinhe Shen Tao Liu Xinhao Liao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第4期121-132,共12页
In the restricted three-body problem(RTBP), if a small body and a planet stably orbit around a central star with almost exactly the same semimajor axis, and thus almost the same mean motion, this phenomenon is called ... In the restricted three-body problem(RTBP), if a small body and a planet stably orbit around a central star with almost exactly the same semimajor axis, and thus almost the same mean motion, this phenomenon is called the coorbital motion, or equivalently, the 1:1 mean motion resonance. The classical expansion of the disturbing function is divergent when the semimajor axis ratio of the small body to the planet is close to unity. Thus, most of the previous studies on the co-orbital dynamics were carried out through numerical integrations or semi-analytical approaches. In this work, we construct an analytical averaged model for the co-orbital motion in the framework of the circular RTBP. This model is valid in the entire coorbital region except in the vicinity of the collision singularity. The results of the analytical averaged model are in good agreement with the numerical averaged model even for moderate eccentricities and inclinations. The analytical model can reproduce the tadpole, horseshoe and quasi-satellite orbits common in the planar problem. Furthermore, the asymmetry of 1:1 resonance and the compound orbits(Icarus 137:293–314) in the general spatial problem can also be obtained from the analytical model. 展开更多
关键词 celestial mechanics-methods analytical-minor planets-asteroids GENERAL
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PyMsOfa:A Python Package for the Standards of Fundamental Astronomy(SOFA)Service
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作者 Jianghui Ji Dongjie Tan +4 位作者 Chunhui Bao Xiumin Huang Shoucun Hu Yao Dong Su Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第12期184-189,共6页
The Standards of Fundamental Astronomy(SOFA)is a service provided by the International Astronomical Union that offers algorithms and software for astronomical calculations,which was released in two versions for FORTRA... The Standards of Fundamental Astronomy(SOFA)is a service provided by the International Astronomical Union that offers algorithms and software for astronomical calculations,which was released in two versions for FORTRAN77 and ANSI C,respectively.In this work,we implement the Python package PyMsOfa for SOFA service by three ways:(1)a Python wrapper package based on a foreign function library for Python(ctypes),(2)a Python wrapper package with the foreign function interface for Python calling C code(cffi)and(3)a Python package directly written in pure Python codes from SOFA subroutines.The package PyMsOfa has fully implemented 247 functions of the original SOFA routines released on 2023 October 11.In addition,PyMsOfa is also extensively examined,which is exactly consistent with those test examples given by the original SOFA.This Python package can be suitable to not only the astrometric detection of habitable planets from the Closeby Habitable Exoplanet Survey mission,but also for the frontier themes of black holes and dark matter related to astrometric calculations and other fields.The source codes are available via http://pypi.org/project/PyMsOfa/and https://github.com/CHES2023/PyMsOfa. 展开更多
关键词 Astrometry and celestial Mechanics-planets and satellites detection-planets and satellites terrestrial planets
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Studying the Equilibrium Points of the Modified Circular Restricted Three-body Problem: The Case of Sun–Haumea System
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作者 INurul Huda B.Dermawan +2 位作者 M.B.Saputra R.Sadikin T.Hidayat 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期232-242,共11页
We intend to study a modified version of the planar Circular Restricted Three-Body Problem(CRTBP) by incorporating several perturbing parameters. We consider the bigger primary as an oblate spheroid and emitting radia... We intend to study a modified version of the planar Circular Restricted Three-Body Problem(CRTBP) by incorporating several perturbing parameters. We consider the bigger primary as an oblate spheroid and emitting radiation while the small primary has an elongated body. We also consider the perturbation from a disk-like structure encompassing this three-body system. First, we develop a mathematical model of this modified CRTBP.We have found there exist five equilibrium points in this modified CRTBP model, where three of them are collinear and the other two are non-collinear. Second, we apply our modified CRTBP model to the Sun–Haumea system by considering several values of each perturbing parameter. Through our numerical investigation, we have discovered that the incorporation of perturbing parameters has resulted in a shift in the equilibrium point positions of the Sun–Haumea system compared to their positions in the classical CRTBP. The stability of equilibrium points is investigated. We have shown that the collinear equilibrium points are unstable and the stability of non-collinear equilibrium points depends on the mass parameter μ of the system. Unlike the classical case, non-collinear equilibrium points have both a maximum and minimum limit of μ for achieving stability. We remark that the stability range of μ in non-collinear equilibrium points depends on the perturbing parameters. In the context of the Sun–Haumea system, we have found that the non-collinear equilibrium points are stable. 展开更多
关键词 celestial mechanics Kuiper Belt:general planets and satellites:dynamical evolution and stability
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A Data-driven Method for Realistic Covariance Prediction of Space Object with Sparse Tracking Data
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作者 Hong-Kang Liu Bin Li +1 位作者 Yan Zhang Ji-Zhang Sang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期220-237,共18页
Covariance of the orbital state of a resident space object(RSO)is a necessary requirement for various space situational awareness tasks,like the space collision warning.It describes an accuracy envelope of the RSO'... Covariance of the orbital state of a resident space object(RSO)is a necessary requirement for various space situational awareness tasks,like the space collision warning.It describes an accuracy envelope of the RSO's location.However,in current space surveillance,the tracking data of an individual RSO is often found insufficiently accurate and sparsely distributed,making the predicted covariance(PC)derived from the tracking data and classical orbit dynamic system usually unrealistic in describing the error characterization of orbit predictions.Given the fact that the tracking data of an RSO from a single station or a fixed network share a similar temporal and spatial distribution,the evolution of PC could share a hidden relationship with that data distribution.This study proposes a novel method to generate accurate PC by combining the classical covariance propagation method and the data-driven approach.Two popular machine learning algorithms are applied to model the inconsistency between the orbit prediction error and the PC from historical observations,and then this inconsistency model is used for the future PC.Experimental results with the Swarm constellation satellites demonstrate that the trained Random Forest models can capture more than 95%of the underlying inconsistency in a tracking scenario of sparse observations.More importantly,the trained models show great generalization capability in correcting the PC of future epochs and other RSOs with similar orbit characteristics and observation conditions.Besides,a deep analysis of generalization performance is carried out to describe the temporal and spatial similarities of two data sets,in which the Jaccard similarity is used.It demonstrates that the higher the Jaccard similarity is,the better the generalization performance will be,which may be used as a guide to whether to apply the trained models of a satellite to other satellites.Further,the generalization performance is also evaluated by the classical Cramer von Misses test,which also shows that trained models have encouraging generalization performance. 展开更多
关键词 celestial mechanics-methods analytical-miscellaneous
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Time Dilation Cosmology
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 CAS 2023年第6期839-864,共26页
This model ties gravitation and celestial mechanics and kinematics directly to time dilation. It is a new theory of cosmology and the evolution of galaxies. Space and time are not two separate things, but two aspects ... This model ties gravitation and celestial mechanics and kinematics directly to time dilation. It is a new theory of cosmology and the evolution of galaxies. Space and time are not two separate things, but two aspects of a single thing, “spacetime”. Whatever affects space, affects time, and vice-versa. If time speeds up, space must contract to maintain the speed of light, c, and when space thickens into a mass, it is harder to evolve forward, and time appears to slow. If spatial events are spinning as time passes, then the forward direction of time is spinning. This is Einstein’s curvature in the forward direction of time. Herein, the basis is outlined for time dilation cosmology in a spacetime/quantum continuum, including the time dilation-based derivation of the mass of the Cosmic Microwave Background Radiation (CMBR), and time dilation formulas are derived for stellar system orbital, and galactic rotation, velocities, the force in time in Newtons, the Hamiltonian, the Hubble shift, the empirical gravitational constant, G, and other formulas, showing their direct relationship to the difference in the rate of time between the far distant observer’s invariant 1 s/s rate of time and the slower rate of time at the coordinate point, proving the universe is not composed of separate bodies moving through space, but is an evolving 3-dimensional holographic continuum containing varying densities evolving forward in the forward direction of time, the 4th dimension, at apparently different rates of time, the velocities merely being compensation for those slower rates of time in a continuum evolving forward overall at c, which is why light propagates at c, even from a moving source. As per General Relativity, if there is no rate of time difference between coordinate points, there is no gravitational attraction between those points, and no gravitationally induced velocity. This model resolves all the major conundrums in astrophysics, eliminating Dark Energy and Dark Matter, and ties astrophysics directly to quantum physics. 展开更多
关键词 GRAVITATION Time celestial Mechanics ISM: Kinematics and Dynamics Cosmology: Theory Galaxies: Evolution
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Modification of the Lagrange-Jacobi Equation and Its Application
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作者 Chingis Omarov Gulnara Omarova 《World Journal of Mechanics》 2023年第6期127-134,共8页
The Lagrange-Jacobi equation is one of the significant tools for the qualitative analysis of the n-body problem. In this paper, we present the modified Lagrange-Jacobi equation by introducing a new formal parameter of... The Lagrange-Jacobi equation is one of the significant tools for the qualitative analysis of the n-body problem. In this paper, we present the modified Lagrange-Jacobi equation by introducing a new formal parameter of n-body problem and propose its application to the dynamical study of clusters of galaxies which are large-scale structures of Universe. We put forward and study a new dynamical problem which is related to the stage of relaxation of observed stationary clusters of galaxies which are considered as a non-equilibrium systems of point masses. We also received the analytical form of the potential energy of such galaxy clusters. One of the applications of this analytical form is the analytical relation between the time  of setting up the virial equilibrium in relaxing clusters of galaxies and the cosmological epoch T. 展开更多
关键词 celestial Mechanics Large-Scale Structure of Universe GALAXIES CLUSTERS Cosmological Epoch
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Orbital evolution of a planet with tidal dissipation in a restricted three-body system
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作者 Wen-Lei Wang Xue-Qing Xu Xin-Hao Liao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第9期79-96,共18页
The angle between planetary spin and the normal direction of an orbital plane is supposed to reveal a range of information about the associated planetary formation and evolution. Since the orbit’s eccentricity and in... The angle between planetary spin and the normal direction of an orbital plane is supposed to reveal a range of information about the associated planetary formation and evolution. Since the orbit’s eccentricity and inclination oscillate periodically in a hierarchical triple body and tidal friction makes the spin parallel to the normal orientation of the orbital plane with a short timescale in an isolated binary system, we focus on the comprehensive effect of third body perturbation and tidal mechanism on the angle. Firstly, we extend the Hut tidal model(1981) to the general spatial case, adopting the equilibrium tide and weak friction hypothesis with constant delay time, which is suitable for arbitrary eccentricity and any angle ? between the planetary spin and normal orientation of the orbital plane. Furthermore, under the constraint of angular momentum conservation, the equations of orbital and ratational motion are given. Secondly, considering the coupled effects of tidal dissipation and third body perturbation, and adopting the quadrupole approximation as the third body perturbation effect, a comprehensive model is established by this work. Finally, we find that the ultimate evolution depends on the timescales of the third body and tidal friction. When the timescale of the third body is much shorter than that of tidal friction, the angle ? will oscillate for a long time,even over the whole evolution;when the timescale of the third body is observably larger than that of the tidal friction, the system may enter stable states, with the angle ? decaying to zero ultimately, and some cases may have a stable inclination beyond the critical value of Lidov-Kozai resonance. In addition, these dynamical evolutions depend on the initial values of the orbital elements and may aid in understanding the characteristics of the orbits of exoplanets. 展开更多
关键词 ASTROMETRY and celestial mechanics:celestial MECHANICS planet-star interactions planets and satellites:dynamical evolution and stability
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A tightly coupled rotational SINS/CNS integrated navigation method for aircraft 被引量:4
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作者 NING Xiaolin YUAN Weiping LIU Yanhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期770-782,共13页
Strapdown inertial navigation system(SINS)/celestial navigation system(CNS)integrated navigation is widely used to achieve long-time and high-precision autonomous navigation for aircraft.In general,SINS/CNS integrated... Strapdown inertial navigation system(SINS)/celestial navigation system(CNS)integrated navigation is widely used to achieve long-time and high-precision autonomous navigation for aircraft.In general,SINS/CNS integrated navigation can be divided into two integrated modes:loosely coupled integrated navigation and tightly coupled integrated navigation.Because the loosely coupled SINS/CNS integrated system is only available in the condition of at least three stars,the latter one is becoming a research hotspot.One major challenge of SINS/CNS integrated navigation is obtaining a high-precision horizon reference.To solve this problem,an innovative tightly coupled rotational SINS/CNS integrated navigation method is proposed.In this method,the rotational SINS error equation in the navigation frame is used as the state model,and the starlight vector and star altitude are used as measurements.Semi-physical simulations are conducted to test the performance of this integrated method.Results show that this tightly coupled rotational SINS/CNS method has the best navigation accuracy compared with SINS,rotational SINS,and traditional tightly coupled SINS/CNS integrated navigation method. 展开更多
关键词 celestial NAVIGATION system(CNS) rotation modulation technology ROTATIONAL STRAPDOWN INERTIAL NAVIGATION system(SINS) ROTATIONAL SINS/CNS integrated NAVIGATION
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Analysis of the wide area differential correction for BeiDou global satellite navigation system 被引量:3
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作者 Ran Li Yue-Ling Cao +6 位作者 Xiao-Gong Hu Cheng-Pan Tang Shan-Shi Zhou Xin Meng Li Liu Ran-Ran Su Zhi-Qiao Chang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第11期17-28,共12页
The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orb... The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orbit and clock corrections conforming with RTCA standards will be broadcast to authorized users. The hybrid constellation and regional monitoring network pose challenges for the high precision separation of orbit and satellite clock corrections. Three correction models of kinematic,dynamic and Two-way Satellite Time Frequency Transfer(TWSTFT)-based dynamic were studied to estimate the satellite orbit and clock corrections. The correction accuracy of the three models is compared and analyzed based on the BDS observation data. Results show that the accuracies(root mean square, RMS) of dual-frequency real-time positioning for the three models are about 1.76 m, 1.78 m and 2.08 m respectively, which are comparable with the performance of WAAS and EGNOS. With dynamic corrections, the precision of Precise Point Positioning(PPP) experiments may reach about 23 cm after convergence. 展开更多
关键词 celestial MECHANICS -methods data ANALYSIS -SPACE VEHICLES
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CHES: A Space-borne Astrometric Mission for the Detection of Habitable Planets of the Nearby Solar-type Stars 被引量:1
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作者 Jiang-Hui Ji Hai-Tao Li +18 位作者 Jun-Bo Zhang Liang Fang Dong Li Su Wang Yang Cao Lei Deng Bao-Quan Li Hao Xian Xiao-Dong Gao Ang Zhang Fei Li Jia-Cheng Liu Zhao-Xiang Qi Sheng Jin Ya-Ning Liu Guo Chen Ming-Tao Li Yao Dong Zi Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第7期32-59,共28页
The Closeby Habitable Exoplanet Survey(CHES) mission is proposed to discover habitable-zone Earth-like planets of nearby solar-type stars(~10 pc away from our solar system) via microarcsecond relative astrometry.The m... The Closeby Habitable Exoplanet Survey(CHES) mission is proposed to discover habitable-zone Earth-like planets of nearby solar-type stars(~10 pc away from our solar system) via microarcsecond relative astrometry.The major scientific objectives of CHES are:to search for Earth Twins or terrestrial planets in habitable zones orbiting100 FGK nearby stars;further to conduct a comprehensive survey and extensively characterize nearby planetary systems.The primary payload is a high-quality,low-distortion,high-stability telescope.The optical subsystem is a coaxial three-mirror anastigmat(TMA) with a 1.2 m-aperture,0°.44 × 0°.44 field of view and 500 nm-900 nm working wave band.The camera focal plane is composed of a mosaic of 81 scientific CMOS detectors each with4 k × 4 k pixels.The heterodyne laser interferometric calibration technology is employed to ensure microarcsecond level(1 μas) relative astrometry precision to meet the requirements for detection of Earth-like planets.The CHES satellite operates at the Sun-Earth L2 point and observes all the target stars for 5 yr.CHES will offer the first direct measurements of true masses and inclinations of Earth Twins and super-Earths orbiting our neighbor stars based on microarcsecond astrometry from space.This will definitely enhance our understanding of the formation of diverse nearby planetary systems and the emergence of other worlds for solar-type stars,and finally provide insights to the evolution of our own solar system. 展开更多
关键词 Astrometry and celestial Mechanics planets and satellites:detection planets and satellites:terrestrial planets stars:solar-type
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Radio frequency compatibility analysis for BDSBAS and GPS/WAAS 被引量:1
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作者 Cheng Liu Wei-Guang Gao +2 位作者 Jun Lu Yi Zhou Shan-Shan Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第8期235-244,共10页
Radio frequency signal compatibility is the basis of interoperability of the Satellite eBased Augmentation System(SBAS).SBAS should abide by relative international radio regulations of International Telecommunication ... Radio frequency signal compatibility is the basis of interoperability of the Satellite eBased Augmentation System(SBAS).SBAS should abide by relative international radio regulations of International Telecommunication Union(ITU) and meet the compatibility requirements of radio frequency signal between the Global Navigation Satellite System(GNSS)/SBAS,in order to avoid negative mutual interference.According to ITU Proposal and related reference and assumptions,the paper made simulation of signal receiving maximum power in the Bei Dou Satellite-Based Augmentation System(BDSBAS)global signal coverage.And then,interference of BDSBAS to Global Positioning System(GPS)/WAAS(Wide Area Augmentation System) on L1/L5 bands were calculated and analyzed,with equivalent carrierto-noise ratio as the evaluation parameter.The result shows that the carrier-to-noise ratio decrease of GPS/WAAS caused by BDSBAS B1 C and B2 a signals are extremely lower than inter-system interference of GPS/WAAS,and thus can be ignored in practical applications.Therefore,BDSBAS will not cause the service performance degradation of GPS and WAAS. 展开更多
关键词 space vehicles methods:data analysis celestial mechanics
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