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No short hair behaviors of ultra-compact stars
European Physical Journal C: Particles and Fields, 2021 In the black hole spacetime, a no short hair theorem was proved, which states that the effective radius of black hole hairs must extend beyond the null circular orbit.
Yan Peng
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Innermost Stable Circular Orbit of a Spinning Particle in Kerr Spacetime [PDF]
, 1997 We study stability of a circular orbit of a spinning test particle in a Kerr spacetime. We find that some of the circular orbits become unstable in the direction perpendicular to the equatorial plane, although the orbits are still stable in the radial ...
A. Abromovici +28 more
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Geometric Calibration of Parameters in the Perpendicular-Orbit Circular Scanning Satellite Camera
Remote SensingPerpendicular-orbit circular scanning satellites overcome the conflict between ground resolution and width observed in traditional optical satellites by using a perpendicular-orbit circular scanning imaging method and splicing along the orbit, achieving ...
Xufeng Zhang +3 more
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Design Method of Orthogonal Circular Orbit Satellite Constellation Based on Geometric Analysis [PDF]
Jisuanji gongcheng, 2020 Orthogonal circular orbit constellation combines the advantages of polar orbit constellation and equatorial orbit constellation to achieve continuous global coverage,improving the coverage performance of pure polar orbit constellation at low and middle ...
BAO Xiang, LEI Lei, SHEN Gaoqing, LI Zhilin
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Coplanar multi-turn rendezvous in near-circular orbit using a low-thrust engine
RUDN Journal of Engineering Research, 2022 The authors describe an algorithm that allows calculating the parameters of maneuvers performed on several turns by the low-thrust engine, which ensure the flight of the active spacecraft to the specified vicinity of the target space object. The movement
Andrey A. Baranov, Adilson Pedro Olivio
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RUDN Journal of Engineering Research, 2021 The basis for ensuring a high level of reliability and safety in dynamic operations is a comprehensive experimental development of products in conditions as close to the real conditions of operation as possible with the use of mathematical and simulation
Veniamin V. Malyshev +3 more
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Orbit Decomposition Method for Rotordynamic Coefficients Identification of Annular Seals
Applied Sciences, 2021 The elliptical orbit whirl model is widely used to identify the frequency-dependent rotordynamic coefficients of annular seals. The existing solution technique of an elliptical orbit whirl model is the transient computational fluid dynamics (CFD) method.
Mingjie Zhang +3 more
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Lyapunov exponent, ISCO and Kolmogorov–Senai entropy for Kerr–Kiselev black hole
European Physical Journal C: Particles and Fields, 2021 Geodesic motion has significant characteristics of space-time. We calculate the principle Lyapunov exponent (LE), which is the inverse of the instability timescale associated with this geodesics and Kolmogorov–Senai (KS) entropy for our rotating Kerr ...
Monimala Mondal +2 more
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Bound on Photon Circular Orbits in General Relativity and Beyond
Galaxies, 2021 The existence of a photon circular orbit can tell us a lot about the nature of the underlying spacetime, since it plays a pivotal role in the understanding of the characteristic signatures of compact objects, namely the quasi-normal modes and shadow ...
Sumanta Chakraborty
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To Circularize or Not To Circularize?—Orbital Evolution of Satellite Galaxies [PDF]
The Astrophysical Journal, 2003 We investigated the orbital evolution of satellite galaxies using numerical simulations. It has been long believed that the orbit suffers circularization due to the dynamical friction from the galactic halo during orbital decay. This circularization was confirmed by numerous simulations where dynamical friction is added as external force. However, some
Hashimoto, Yoshikazu +2 more
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