Small celestial body exploration is of great significance to deep space activities. The dynamics and control of orbits around small celestial bodies is of top priority in the exploration research. It includes the mode...Small celestial body exploration is of great significance to deep space activities. The dynamics and control of orbits around small celestial bodies is of top priority in the exploration research. It includes the modeling of dynamics environment and the orbital dynamics mechanism. This paper introduced state-ofthe-art researches, major challenges, and future trends in this field. Three topics are mainly discussed： the gravitational field modeling of irregular-shaped small celestial bodies, natural orbital dynamics and control, and controlled orbital dynamics. Finally, constructive suggestions are made for China’s future space exploration missions.展开更多
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
In history,the Earth has encountered frequent and massive impacts.Until today,it is still a collided target for Potentially Hazardous Objects(PHOs),gradually making planetary defense a concerned and important research...In history,the Earth has encountered frequent and massive impacts.Until today,it is still a collided target for Potentially Hazardous Objects(PHOs),gradually making planetary defense a concerned and important research topic in the field of aerospace science.Against this background,this work clarifies and discusses some important scientific issues and various critical technologies of planetary defense.First,the current status of planetary defense research is summarized.Subsequently,the classification and characteristics of PHOs are introduced,focusing on their potential impact on planetary defense and related scientific research issues.For the purpose of protecting the Earth and maintaining space safety,the monitoring and characterization,deflection,and mitigation of PHOs have basically occupied all the attention of planetary defense researchers.Therefore,the critical technologies in planetary defense are discussed from these three aspects,and are also compared and analyzed in depth.Based on the current research progress in planetary defense,the challenges for planetary defense are discussed,and future development directions are also analyzed.Finally,a summary of the entire study is provided.展开更多
文摘Small celestial body exploration is of great significance to deep space activities. The dynamics and control of orbits around small celestial bodies is of top priority in the exploration research. It includes the modeling of dynamics environment and the orbital dynamics mechanism. This paper introduced state-ofthe-art researches, major challenges, and future trends in this field. Three topics are mainly discussed： the gravitational field modeling of irregular-shaped small celestial bodies, natural orbital dynamics and control, and controlled orbital dynamics. Finally, constructive suggestions are made for China’s future space exploration missions.
文摘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.
基金supported by the Strategic Priority Research Program on Space Science,the Chinese Academy of Sciences(No.XDA1502030505)。
文摘In history,the Earth has encountered frequent and massive impacts.Until today,it is still a collided target for Potentially Hazardous Objects(PHOs),gradually making planetary defense a concerned and important research topic in the field of aerospace science.Against this background,this work clarifies and discusses some important scientific issues and various critical technologies of planetary defense.First,the current status of planetary defense research is summarized.Subsequently,the classification and characteristics of PHOs are introduced,focusing on their potential impact on planetary defense and related scientific research issues.For the purpose of protecting the Earth and maintaining space safety,the monitoring and characterization,deflection,and mitigation of PHOs have basically occupied all the attention of planetary defense researchers.Therefore,the critical technologies in planetary defense are discussed from these three aspects,and are also compared and analyzed in depth.Based on the current research progress in planetary defense,the challenges for planetary defense are discussed,and future development directions are also analyzed.Finally,a summary of the entire study is provided.
