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1.
We study the problem of the reconstruction of a non-stationary space symmetrical regular planar potential of the gravitating system on a family of evolving types of orbits being used in the dynamics of stationary stellar systems. An application of such an inverse problem to the dynamical evolution of stellar systems with variable masses is given. The general form of the evolving orbit which we use when writing out the differential equations for non-stationary potential may also be interpreted as an osculating orbit of the perturbed Keplerian motion. In this case we are making an additional transformation of the basic equation of the problem and demonstrating an appropriate example of the construction of a non-stationary potential of a gravitating system. In connection with the stellar dynamical character of our inverse problem, we also give a generalized form of its basic equation in a rotating coordinate system. 相似文献
2.
This paper focuses on some aspects of the motion of a small particle moving near the Lagrangian points of the Earth–Moon system.
The model for the motion of the particle is the so-called bicircular problem (BCP), that includes the effect of Earth and
Moon as in the spatial restricted three body problem (RTBP), plus the effect of the Sun as a periodic time-dependent perturbation
of the RTBP. Due to this periodic forcing coming from the Sun, the Lagrangian points are no longer equilibrium solutions for
the BCP. On the other hand, the BCP has three periodic orbits (with the same period as the forcing) that can be seen as the
dynamical equivalent of the Lagrangian points. In this work, we first discuss some numerical methods for the accurate computation
of quasi-periodic solutions, and then we apply them to the BCP to obtain families of 2-D tori in an extended neighbourhood
of the Lagrangian points. These families start on the three periodic orbits mentioned above and they are continued in the
vertical (z and ż) direction up to a high distance. These (Cantor) families can be seen as the continuation, into the BCP, of the Lyapunov
family of periodic orbits of the Lagrangian points that goes in the (z, ż) direction. These results are used in a forthcoming work [9] to find regions where trajectories remain confined for a
very long time. It is remarkable that these regions seem to persist in the real system.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
A. Kyrala 《Earth, Moon, and Planets》1981,24(3):345-348
The problem of determination of the radial distribution of the planetary orbits is approached under the assumption that the average present radial sizes of the orbits were already determined when the protoplanetary cloud flattened by initial angular momentum aggregated into a set of concentric rings from which the planetary material was ultimately collected. The object of this argument is to derive a consistent stationary distribution of orbits so that the problem of the non-stationary formation of the orbital rings is not here considered. Under the flattening assumption the 3D Poisson equation is replaced by the 2D Helmholtz equation (inhomogeneous) which is solved by use of an averaging theorem generalization of the well-known averaging theorem for the homogeneous Helmholtz equation. Augmenting the ring potentials obtained by specializing the mass distribution in the disk by a solar potential term and a rotational potential, differentiation leads to a generalization of the Kepler 3D law suitable for the many-body problem of a solar system with circular orbits. In this way a system of transcendental equations involving Bessel functions of the first and second kind are obtained which must be satisfied by the orbital radii. Naturally the restriction to circular orbits represents only an approximation to the orbital determination problem, but considering that no arguments have previously been available for the determination even of circular orbits it would seem to represent an advance. 相似文献
4.
We study the equilibrium points and the zero-velocity curves of Chermnykh’s problem when the angular velocity ω varies continuously and the value of the mass parameter is fixed. The planar symmetric simple-periodic orbits are determined numerically and they are presented for three values of the parameter ω. The stability of the periodic orbits of all the families is computed. Particularly, we explore the network of the families when the angular velocity has the critical value ω = 2√2 at which the triangular equilibria disappear by coalescing with the collinear equilibrium point L1. The analytic determination of the initial conditions of the family which emanate from the Lagrangian libration point L1 in this case, is given. Non-periodic orbits, as points on a surface of section, providing an outlook of the stability regions, chaotic and escape motions as well as multiple-periodic orbits, are also computed. Non-linear stability zones of the triangular Lagrangian points are computed numerically for the Earth–Moon and Sun–Jupiter mass distribution when the angular velocity varies. 相似文献
5.
We have studied periodic orbits generated by Lagrangian solutions of the restricted three body problem when one of the primaries
is an oblate body. We have determined the periodic orbits for different values of μ, h and A (h is energy constant, μ is mass ratio of the two primaries and A is an oblateness factor). These orbits have been determined by giving displacements along the tangent and normal to the mobile
coordinates as defined by Karimov and Sokolsky (Celest. Mech. 46:335, 1989). These orbits have been drawn by using the predictor-corrector method. We have also studied the effect of oblateness by
taking some fixed values of μ, A and h. As starters for our method, we use some known periodic orbits in the classical restricted three body problem. 相似文献
6.
The effect of the eccentricity of a planet’s orbit on the stability of the orbits of its satellites is studied. The model
used is the elliptic Hill case of the planar restricted three-body problem. The linear stability of all the known families
of periodic orbits of the problem is computed. No stable orbits are found, the majority of them possessing one or two pairs
of real eigenvalues of the monodromy matrix, while a part of a family with complex instability is found. Two families of periodic
orbits, bifurcating from the Lagrangian points L1, L2 of the corresponding circular case are found analytically. These orbits are very unstable and the determination of their
stability coefficients is not accurate, so we compute the largest Liapunov exponent in their vicinity. In all cases these
exponents are positive, indicating the existence of chaotic motions 相似文献
7.
We study numerically the asymmetric periodic orbits which emanate from the triangular equilibrium points of the restricted
three-body problem under the assumption that the angular velocity ω varies and for the Sun–Jupiter mass distribution. The
symmetric periodic orbits emanating from the collinear Lagrangian point L
3, which are related to them, are also examined. The analytic determination of the initial conditions of the long- and short-period
Trojan families around the equilibrium points, is given. The corresponding families were examined, for a combination of the
mass ratio and the angular velocity (case of equal eigenfrequencies), and also for the critical value ω = 2
, at which the triangular equilibria disappear by coalescing with the inner collinear equilibrium point L
1. We also compute the horizontal and the vertical stability of these families for the angular velocity parameter ω under consideration.
Series of horizontal–critical periodic orbits of the short-Trojan families with the angular velocity ω and the mass ratio
μ as parameters, are given. 相似文献
8.
Periodic orbits in the photogravitational restricted problem with the smaller primary an oblate body
In this paper, we have studied periodic orbits generated by Lagrangian solutions of the restricted three body problem when
more massive body is a source of radiation and the smaller primary is an oblate body. We have determined periodic orbits for
fixed values of μ, σ and different values of p and h (μ mass ratio of the two primaries, σ oblate parameter, p radiation parameter and h energy constant). These orbits have been determined by giving displacements along the tangent and normal to the mobile co-ordinates
as defined by Karimov and Sokolsky (in Celest. Mech. 46:335, 1989). These orbits have been drawn by using the predictor-corrector method. We have also studied the effect of radiation pressure
on the periodic orbits by taking some fixed values of μ and σ. 相似文献
9.
Strategies for plane change of Earth orbits using lunar gravity and derived trajectories of family G
C. F. de Melo E. E. N. Macau O. C. Winter 《Celestial Mechanics and Dynamical Astronomy》2009,103(4):281-299
The dynamics of the circular restricted three-body Earth-Moon-particle problem predicts the existence of the retrograde periodic
orbits around the Lagrangian equilibrium point L1. Such orbits belong to the so-called family G (Broucke, Periodic orbits
in the restricted three-body problem with Earth-Moon masses, JPL Technical Report 32–1168, 1968) and starting from them it
is possible to define a set of trajectories that form round trip links between the Earth and the Moon. These links occur even
with more complex dynamical systems as the complete Sun-Earth-Moon-particle problem. One of the most remarkable properties
of these trajectories, observed for the four-body problem, is a meaningful inclination gain when they penetrate into the lunar
sphere of influence and accomplish a swing-by with the Moon. This way, when one of these trajectories returns to the proximities
of the Earth, it will be in a different orbital plane from its initial Earth orbit. In this work, we present studies that
show the possibility of using this property mainly to accomplish transfer maneuvers between two Earth orbits with different
altitudes and inclinations, with low cost, taking into account the dynamics of the four-body problem and of the swing-by as
well. The results show that it is possible to design a set of nominal transfer trajectories that require ΔV
Total less than conventional methods like Hohmann, bi-elliptic and bi-parabolic transfer with plane change. 相似文献
10.
Analysis of periodic orbits in the Saturn-Titan system using the method of Poincare section surfaces
We explore the periodic orbits and the regions of quasi-periodic motion around both the primaries in the Saturn-Titan system
in the framework of planar circular restricted three-body problem. The location, nature and size of periodic and quasi-periodic
orbits are studied using the numerical technique of Poincare surface of sections. The maximum amplitude of oscillations about
the periodic orbits is determined and is used as a parameter to measure the degree of stability in the phase space for such
orbits. It is found that the orbits around Saturn remain around it and their stability increases with the increase in the
value of Jacobi constant C. The orbits around Titan move towards it with the increase in C. At C=3.1, the pericenter and apocenter are 358.2 and 358.5 km, respectively. No periodic or quasi-periodic orbits could be found
by the present method around the collinear Lagrangian point L
1 (0.9569373834…). 相似文献
11.
Szebehely's renowned equation given in 1974, allowing for potential determination from a given orbit or family of orbits, is proved to be equivalent with an equation deduced in 1963 by Drǎmbǎ. This basic equation in the inverse problem of dynamics, for which the denomination of Drǎmbǎ –Szebehely equation is proposed, is generalized for the motion in the n-dimensional Euclidean space. A method for the determination of the potential function from motion equations is extended to this space. 相似文献
12.
The concept of closest approach is analyzed in Hill’s problem, resulting in a partitioning of the position space. The different
behavior between the direct and retrograde motion is explained analytically, resulting in a simple estimate of the variation
of Hill’s periodic and quasi-circular orbits as a function of the Jacobi constant. The local behavior of the orbits on the
zero velocity surfaces and an analytical definition of local escape and capture in Hill’s problem are also given. 相似文献
13.
We consider a model that describes the evolution of distant satellite orbits and that refines the solution of the doubly averaged
Hill problem. Generally speaking, such a refinement was performed previously by J. Kovalevsky and A.A. Orlov in terms of Zeipel’s
method by constructing a solution of the third order with respect to the small parameter m, the ratio of the mean motions of the planet and the satellite. The analytical solution suggested here differs from the solutions
obtained by these authors and is closest in form to the general solution of the doubly averaged problem (∼m
2). We have performed a qualitative analysis of the evolutionary equations and conditions for the intersection of satellite
orbits with the surface of a spherical planet with a finite radius. Using the suggested solution, we have obtained improved
analytical time dependences of the elements of evolving orbits for a number of distant satellites of giant planets compared
to the solution of the doubly averaged Hill problem and, thus, achieved their better agreement with the results of our numerical
integration of the rigorous equations of perturbed motion for satellites. 相似文献
14.
M. K. Ammar 《Astrophysics and Space Science》2008,313(4):393-408
In this paper the effect of solar radiation pressure on the location and stability of the five Lagrangian points is studied,
within the frame of elliptic restricted three-body problem, where the primaries are the Sun and Jupiter acting on a particle
of negligible mass. We found that the radiation pressure plays the rule of slightly reducing the effective mass of the Sun
and changes the location of the Lagrangian points. New formulas for the location of the collinear libration points were derived.
For large values of the force ratio β, we found that at β=0.12, the collinear point L3 is stable and some families of periodic orbits can be drawn around it. 相似文献
15.
L. Benet T. H. Seligman D. Trautmann 《Celestial Mechanics and Dynamical Astronomy》1998,71(3):167-189
We study the scattering motion of the planar restricted three‐body problem for small mass parameters μ. We consider the symmetric
periodic orbits of this system with μ = 0 that collide with the singularity together with the circular and parabolic solutions
of the Kepler problem. These divide the parameter space in a natural way and characterize the main features of the scattering
problem for small non‐vanishing μ. Indeed, continuation of these orbits yields the primitive periodic orbits of the system
for small μ. For different regions of the parameter space, we present scattering functions and discuss the structure of the
chaotic saddle. We show that for μ < μc and any Jacobi integral there exist departures from hyperbolicity due to regions of
stable motion in phase space. Numerical bounds for μc are given.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
In this paper we consider a restricted equilateral four-body problem where a particle of negligible mass is moving under the Newtonian gravitational attraction of three masses (called primaries) which move on circular orbits around their center of masses such that their configuration is always an equilateral triangle (Lagrangian configuration). We consider the case of two bodies of equal masses, which in adimensional units is the parameter of the problem. We study numerically the existence of families of unstable periodic orbits, whose invariant stable and unstable manifolds are responsible for the existence of homoclinic and heteroclinic connections, as well as of transit orbits traveling from and to different regions. We explore, for three different values of the mass parameter, what kind of transits and energy levels exist for which there are orbits with prescribed itineraries visiting the neighborhood of different primaries. 相似文献
17.
Richard Schwarz Markus Gyergyovits Rudolf Dvorak 《Celestial Mechanics and Dynamical Astronomy》2004,90(1-2):139-148
The orbits of real asteroids around the Lagrangian points L4 and L 5of Jupiter with large inclinations (i > 20°) were integrated for 50 Myrs. We investigated the stability with the aid of the
Lyapunov characteristic exponents (LCE) but tested also two other methods: on one hand we integrated four neighbouring orbits
for each asteroid and computed the maximum distance in every group, on the other hand we checked the variation of the Delaunay
element H of the asteroid. In a second simulation – for a grid of initial eccentricity versus initial inclination – we examined the
stability of the orbits around both Lagrangian points for 20° < i < 55° and 0.0 < e < 0.20. For the initial semimajor axes
we have chosen the one ofJupiter(a = 5.202 AU). We determined the stability with the aid of the LCEs and also the maximum
eccentricity of the orbits during the whole integration time. The region around L4 turned out to be unstable for large inclinations and eccentricities (i > 55° and e > 0.12). The stable region shrinks for
orbits around L5: we found that they become unstable already for i > 45° and e > 0.10. We interpret it as a first hint why we observe more
Trojans around the leading Lagrangian point. The results confirm the stability behaviour of the real Trojans which we computed
in the first part of the paper. 相似文献
18.
Sándor Molnár 《Celestial Mechanics and Dynamical Astronomy》1981,25(1):81-88
It is shown, that the potential obtained from Joukovsky's formula, corresponding to a given family of orbits is a general solution of Szebehely's equation. Then it is shown how a general solution of Szebehely's equation can be obtained from its particular solution. This method is applied to several examples. Potentials generating families of concentric elliptic orbits and families of orbits of conic sections are determined. Finally, the inverse Keplerian problem is solved using Szebehely's equation in polar coordinates. 相似文献
19.
Boris Garfinkel 《Celestial Mechanics and Dynamical Astronomy》1985,36(1):19-45
E.W. Brown conjectured (1911) that the family of the long-periodic orbits in the Troian case of the restricted problem of three bodies terminates in an asymptotic orbit passing through the Lagrangian point L3 at t=±∞. In 1977 the author showed that such an orbit deviates from L3 by the epicyclic term mg (±∞). It is shown here that $$g\left( { \pm \infty } \right) = 0,$$ so that the Brown conjecture regarding L3 is false. Contrary to what Brown believed, there is an entire family ofhomoclinic orbits, doubly asymptotic to short-periodic orbits around L3. In the complex z-plane of the Poincaré eccentric variables, the latter orbits are circles of radius mR, with R bounded away from zero. The kinematics of the homoclinic family is investigated here in some detail. 相似文献
20.
S. Grigoriadou G. Bozis B. Elmabsout 《Celestial Mechanics and Dynamical Astronomy》1999,74(3):211-221
Szebehely’s equation is a first order partial differential equation relating a given family of orbits f (x, y) = q traced
by a unit mass material point, the total energy E=E(f), and the unknown potential V=V (x, y) which produces the family. Although
linear in V, this equation cannot generally be solved. In this paper we develop the reasoning for finding several cases for
which Szebehely’s equation can be solved by quadratures.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献