Orbital elements of five close visual binary stars     

M. Scardia  J.‐L. Prieur  E. Aristidi  L. Koechlin 《Astronomische Nachrichten》2000,321(4):255-262

Revised orbital elements of the visual binary stars STT 2, STT 4, BU 1015, STT 6 and BU 395 are given. Dynamical parallaxes and total masses of the systems have been calculated.  相似文献   

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徐天河  贺凯飞 《大地测量与地球动力学》2008,28(2):81-85

??????????CHAMP?????????????????????????????н?????1???????????С?????LS??????????CHAMP?????????????????????????????????????????????????????????????????????????????????????CHAMP??????????У???????????????????????????1?GFZ????????????1???? CHAMP????RSO????????????????????????20???????(5??100) m ²s ^-2??С??????????????LS????????????60??60???????????????????EIGEN??CG03C??EIGEN2???????б?????????????????????Ч?????????????????CHAMP????????????????????LS???????????????ε?EGM96??EIGEN1S??EIGEN2????  相似文献   

Inhomogeneous potentials producing homogeneous orbits     

G. Bozis  M.-C. Anisiu  C. Blaga 《Astronomische Nachrichten》1997,318(5):313-318

We prove that, in general, a given two-dimensional inhomogeneous potential V(x,y) does not allow for the creation of homogeneous families of orbits. Yet, depending on the case at hand, if the given potential satisfies certain conditions, this potential is compatible either with one (or two) monoparametric homogeneous families of orbits or at most with five such familes. The orbits are then found on the grounds of the given potential.  相似文献   

Vertical stability of periodic solutions around the triangular equilibrium points     

E. Perdios  C. G. Zagouras 《Celestial Mechanics and Dynamical Astronomy》1991,51(1):75-81

The vertical stability character of the families of short and long period solutions around the triangular equilibrium points of the restricted three-body problem is examined. For three values of the mass parameter less than equal to the critical value of Routh (μ _R ) i.e. for μ = 0.000953875 (Sun-Jupiter), μ = 0.01215 (Earth-Moon) and μ = μ _R = 0.038521, it is found that all such solutions are vertically stable. For μ > (μ _R ) vertical stability is studied for a number of ‘limiting’ orbits extended to μ = 0.45. The last limiting orbit computed by Deprit for μ = 0.044 is continued to a family of periodic orbits into which the well known families of long and short period solutions merge. The stability characteristics of this family are also studied.  相似文献   

Periodic orbits in three-dimensional planetary systems     

S. Ichtiaroglou  K. Katopodis  Michalodimitrakis 《Journal of Astrophysics and Astronomy》1989,10(4):367-380

Three-dimensional planetary systems are studied, using the model of the restricted three-body problem for Μ =.001. Families of three-dimensional periodic orbits of relatively low multiplicity are numerically computed at the resonances 3/1, 5/3, 3/5 and 1/3 and their stability is determined. The three-dimensional orbits are found by continuation to the third dimension of the vertical critical orbits of the corresponding planar problem  相似文献   

On the dynamics in the asteroids belt. Part II: Detailed study of the main resonances     

Alessandro Morbidelli  Antonio Giorgilli 《Celestial Mechanics and Dynamical Astronomy》1989,47(2):173-204

The general theory exposed in the first part of this paper is applied to the following resonances with Jupiter's motion : 3/2, 2/1, 5/2, 3/1, 7/2, 4/1; these are the most relevant resonances for the asteroids. The whole analysis is performed in the framework of the spatial problem of three bodies, both in the circular and in the elliptic case. The results are also compared with the observed distribution of the asteroids.  相似文献   

Orbital structure of self-consistent triaxial stellar systems     

Roberto O. Aquilano  Juan C. Muzzio  Hugo D. Navone  Alejandra F. Zorzi 《Celestial Mechanics and Dynamical Astronomy》2007,99(4):307-324

We used a multipolar code to create, through the dissipationless collapses of systems of 1,000,000 particles, three self-consistent triaxial stellar systems with axial ratios corresponding to those of E4, E5 and E6 galaxies. The E5 and E6 models have small, but significant, rotational velocities although their total angular momenta are zero, that is, they exhibit figure rotation; the rotational velocity decreases with decreasing flattening of the models and for the E4 model it is essentially zero. Except for minor changes, probably caused by unavoidable relaxation effects, the systems are highly stable. The potential of each system was subsequently approximated with interpolating formulae yielding smooth potentials, stationary for the non-rotating model and stationary in the rotating frame for the rotating ones. The Lyapunov exponents could then be computed for randomly selected samples of the bodies that make up the different systems, allowing the recognition of regular and partially and fully chaotic orbits. Finally, the regular orbits were Fourier analyzed and classified using their locations on the frequency map. As it could be expected, the percentages of chaotic orbits increase with the flattening of the system. As one goes from E6 through E4, the fraction of partially chaotic orbits relative to that of fully chaotic ones increases, with the former surpassing the latter in model E4; the likely cause of this behavior is that triaxiality diminishes from E6 through E4, the latter system being almost axially symmetric. We especulate that some of the partially chaotic orbits may obey a global integral akin to the long axis component of angular momentum. Our results show that is perfectly possible to have highly stable triaxial models with large fractions of chaotic orbits, but such systems cannot have constant axial ratios from center to border: a slightly flattened reservoir of highly chaotic orbits seems to be mandatory for those systems.  相似文献   

Occurrence of Planetary Rings with Shepherds     

Luis Benet 《Celestial Mechanics and Dynamical Astronomy》2001,81(1-2):123-128

We consider the system of planetary rings with shepherds as a restricted three or four-body problem, neglecting interactions between ring particles. We show that the generic occurrence of rings for the case of rotating short-range potentials can be extended to the case of gravitational potentials. The consecutive collision periodic orbits created by saddle-center bifurcations are of central importance.  相似文献   

Computing periodic orbits of the three-body problem: Effective convergence of Newton’s method on the surface of section     

V.?S.?Kalantonis  V.?V.?Markellos  E.?A.?PerdiosEmail author 《Astrophysics and Space Science》2005,298(3):441-451

We consider Newton’s method for computing periodic orbits of dynamical systems as fixed points on a surface of section and seek to clarify and evaluate the method’s uncertainty of convergence. Several fixed points of various multiplicities, both stable and unstable are computed in a new version of Hill’s problem. Newton’s method is applied with starting points chosen randomly inside the maximum possible—for any method—circle of convergence. The employment of random starting points is continued until one of them leads to convergence, and the process is repeated a thousand times for each fixed point. The results show that on average convergence occurs with very few starting points and non-converging iterations being wasted.  相似文献   

Spectroscopic binaries near the north Galactic pole paper 24: HD 106104, 109281, 109463 and 110743     

R. F. Griffin 《Journal of Astrophysics and Astronomy》2001,22(2-3):187-211

The four stars treated in this paper have been under observation with photoelectric radial-velocity spectrometers for many years. They have proved to be binaries with periods of 30, 1828, 1514 and 822 days respectively; the orbits are of modest eccentricity apart from that of HD 110743 which is indistinguishable from a circle. The mass functions are small, and no companion has been observed for any of the stars. HD 110743, a K dwarf, is much the nearest of the four, and its orbit is of short enough period for the photocentric motion to have been recognized byHipparcos. An eleventh-magnitude star rather more than 1≈ away from HD 106104 is shown to be a genuine physical companion, with practically identical radial velocity, proper motion and distance modulus, although the projected separation is about 13,000 AU.  相似文献