共查询到20条相似文献，搜索用时 15 毫秒
1.
Radial,transverse and normal satellite position perturbations due to the geopotential 总被引：1，自引：0，他引：1
Perturbations in the position of a satellite due to the Earth's gravitational effects are presented. The perturbations are given in the radial, transverse (or alongtrack) and normal (or cross-track) components. The solution is obtained by projecting the Kepler element perturbations obtained by Kaula [Kaula, 1966] into each of the three components. The resulting perturbations are presented in a form analogous to the form of Kaula's solution which facilitates implementation and interpretation. 相似文献
2.
3.
Position and velocity perturbations in the orbital frame in terms of classical element perturbations
Stefano Casotto 《Celestial Mechanics and Dynamical Astronomy》1993,55(3):209-221
The transformation of classical orbit element perturbations to perturbations in position and velocity in the radial, transverse and normal directions of the orbital frame is developed. The formulation is given for the case of mean anomaly perturbations as well as for eccentric and true anomaly perturbations. Approximate formulas are also developed for the case of nearly circular orbits and compared with those found in the literature. 相似文献
4.
Stefano Casotto 《Celestial Mechanics and Dynamical Astronomy》1993,55(3):223-241
Kaula's celebrated solution to the problem of satellite motion in the gravitational field of a rigid body is transformed to give the perturbation spectra in both position and velocity in the radial, transverse and normal directions of the orbital reference frame. This work is an extension and a refinement of the theory of orbital perturbations due to the geopotential previously published by Rosborough and Tapley (1987). 相似文献
5.
The formulae for the perturbations in radial, transverse and binormal components of the Earth artificial satellite motion have been derived. Perturbations due to the tesseral part of the geopotential are considered. The geopotential expressed in terms of the orbital elements has the form proposed by Wnuk (1988). The formulae for the perturbations have been obtained using the Hori (1966) method. They can be effectively applied in calculation of the perturbations in the components including the coefficients of the high order and degree tesseral harmonics. The derived formulae reveal no singularities at zero eccentricity. 相似文献
6.
In this paper, starting with the Szebehely and Bond (1983) equation, we rediscuss the regularization and linearization of the perturbed planar two-body problem.We study the generalization of the Sundman's (1912) transformation proposed by Szebehely and Bond and obtain the radial and transverse perturbations (represented by powers of the radial distance r), which can be linearized with these transformations. In this way we generalize some previous results of Belen'kii (1981a, b) and Szebehely and Bond (1983).We also consider another generalization of Sundman's transformation, introduced by Cidet al. (1983), in the case when the radial and transverse perturbations are presented by polynomials in the reciprocal of the distance. As a consequence we give a partial answer to a problem suggested by Szebehely and Bond (1983). 相似文献
7.
Stefano Casotto 《Celestial Mechanics and Dynamical Astronomy》1995,62(1):1-22
A new method for calculating the perturbation spectrum in the framework of Kaula's linear satellite theory (LST) is introduced. The novelty of this approach consists in using recent results on the spectral decomposition of the perturbation frequencies in LST to provide a closed formulation for the amplitude and the phase of each line in the perturbation spectrum. The theory presented here can be applied to perturbations in the elements or in the radial and transverse directions due to the geopotential or to the tides. Separate algorithms are developed for application to orbits with circulating or frozen perigee. 相似文献
8.
S. V. Sazonov 《Planetary and Space Science》1991,39(12):1667-1671
The non-linear regime of electrostatic perturbations of the equatorial ionospheric F-region generated by Rayleigh-Taylor instability has been discussed, taking into account conductivity along magnetic field lines. A closed non-linear equation has been derived in the stationary limit for the polarization electric field potential. It coincides with the Karman equation of an ideal liquid. To solve the equation, the averaged variational Whitham method has been proposed. Some solutions localized along and across the geomagnetic field, B, as well as quasi-periodic solutions in the transverse direction, have been investigated. Non-linear longitudinal localization of perturbations has been shown to be due to electron-ion collisions. 相似文献
9.
P. D. Ariel 《Astrophysics and Space Science》1988,141(1):141-149
The gravitational instability of an incompressible, infinitely conducting plasma layer of finite thickness surrounded a non-conducting matter has been investigated taking into account the effect of the finite Larmor radius. The magnetic field is assumed to be directed parallel to the interfaces. Only the perturbations transverse to the magnetic field are considered, though both the symmetric and asymmetric nature of the perturbations are taken into account. Using the normal mode technique, dispersion relations are obtained.It is found that the finite larmor radius has, in general, a stabilizing influence on the configuration. Even when the system is thoroughly unstable, it has been shown that there exists a critical value of the wave-number, such that the motion is stabilized for wave-numbers of perturbations exceeding this critical value. 相似文献
10.
We analyse the behaviour of linear magnetohydrodynamic perturbations of a coronal arcade modelled by a half-cylinder with an azimuthal magnetic field and non-uniform radial profiles of the plasma pressure, temperature, and the field. Attention is paid to the perturbations with short longitudinal (in the direction along the arcade) wavelengths. The radial structure of the perturbations, either oscillatory or evanescent, is prescribed by the radial profiles of the equilibrium quantities. Conditions for the corrugation instability of the arcade are determined. It is established that the instability growth rate increases with decreases in the longitudinal wavelength and the radial wave number. In the unstable mode, the radial perturbations of the magnetic field are stronger than the longitudinal perturbations, creating an almost circularly corrugated rippling of the arcade in the longitudinal direction. For coronal conditions, the growth time of the instability is shorter than one minute, decreasing with an increase in the temperature. Implications of the developed theory for the dynamics of coronal active regions are discussed. 相似文献
11.
M. Atiqur Rahman 《Astrophysics and Space Science》2012,341(2):477-484
Waves propagating in the relativistic electron-positron or ions plasma are investigated in a frame of two-fluid equations using the 3+1 formalism of general relativity developed by Thorne, Price and Macdonald (TPM). The plasma is assumed to be freefalling in the radial direction toward the event horizon due to the strong gravitational field of a Schwarzschild black hole. The local dispersion relations for transverse and longitudinal waves have been derived, in analogy with the special relativistic formulation as explained in an earlier paper, to take account of relativistic effects due to the event horizon using WKB approximation. 相似文献
12.
含粘滞的弱磁化吸积盘的非轴对称脉动不稳定性 总被引：1，自引：0，他引：1
本文讨论了一种含扩散型粘滞的弱磁化等温吸积盘模型．在作者原有工作的基础上研究了吸积盘对非轴对称扰动（含径向、环向和垂向三个方向的扰动）所表现的脉动不稳定性．结果表明，径向扰动是最重要、最根本的扰动：在无径向扰动时，吸积盘中不存在环向扰动与垂向扰动所产生的脉动不稳定性．在径向扰动存在时，吸积盘除了可能存在纯径向脉动不稳定性外，还可能存在由于径向扰动与垂向扰动的耦合所引起的轴对称脉动不稳定性，以及由于径向扰动与环向扰动的耦合所引起的非轴对称脉动不稳定性．当上述三个方向的扰动并存时，对应的非轴对称脉动不稳定性也可能存在． 相似文献
13.
The magnetohydrodynamic stability of a streaming liquid cylinder subject to surface tension and pervaded by a magnetic vacuum field has been elaborated for all axisymmetric and non-axisymmetric disturbances. The dispersion relation is obtained and studied analytically and numerically. the streaming has always a destabilizing effect. The axial magnetic fields inside and outside the jet have always stabilizing effects for all perturbations. The transverse magnetic field has a destabilizing effect. However, if the axial field intensity is so high and paramount over that the transverse field, the destabilizing character of the model is suppressed. The latter is satisfied if the Alfvén wave velocity is greater than the equilibrium liquid velocity. 相似文献
14.
In this paper we give a detailed general relativistic formulation of the study of structure and stability of charged fluid
disks around compact objects like black holes neglecting the self-gravitation of the disk itself. Having presented the general
equations for equilibrium as well as for perturbations we solve explicitly the cases of rigidly and differentially rotating
thin disks, with constant charge density and zero pressure, confined to the equatorial plane of the black hole. By using normal
mode analysis we have analysed the stability of such disks under purely radial perturbations and find that the disks are generally
stable.
On leave of absence from Government College, Jagadalpur 494005 相似文献
15.
Hans Rickman Marc Fouchard Christiane Froeschlé Giovanni B. Valsecchi 《Celestial Mechanics and Dynamical Astronomy》2008,102(1-3):111-132
We present Monte Carlo simulations of the dynamical evolution of the Oort cloud over the age of the Solar System, using an initial sample of one million test comets without any cloning. Our model includes perturbations due to the Galactic tide (radial and vertical) and passing stars. We present the first detailed analysis of the injection mechanism into observable orbits by comparing the complete model with separate models for tidal and stellar perturbations alone. We find that a fundamental role for injecting comets from the region outside the loss cone (perihelion distance q > 15 AU) into observable orbits (q < 5 AU) is played by stellar perturbations. These act in synergy with the tide such that the total injection rate is significantly larger than the sum of the two separate rates. This synergy is as important during comet showers as during quiescent periods and concerns comets with both small and large semi-major axes. We propose different dynamical mechanisms to explain the synergies in the inner and outer parts of the Oort Cloud. We find that the filling of the observable part of the loss cone under normal conditions in the present-day Solar System rises from <1% for a < 20 000 AU to about 100% for a ? 100 000 AU. 相似文献
16.
Exact solutions have been found to the Fokker-Planck equations, incorporating stochastic velocity changes and modelling particles moving in an inverse square central force field under an inverse square collision frequency. The solutions for the velocity distribution contain a combination of collisional and dynamical (reversible) heating. At a general position, there are two populations each with three distinct temperatures, one normal to the orbital plane and the others closely parallel and perpendicular to the mean orbit. Collisional heating is strong and most readily detected in the secondary component of gas which reaches upstream directions along indirect orbits (attractive central force). For interplanetary helium gas reaching 1 a.u., the collisional heating ranges from effective transverse increase of 200 K and radial increase of 1500 K in the downstream wake, to several thousand K increase in radial temperature of the secondary component transverse to the initial gas stream. In interpreting 584 Å sky background radiation observations, the dynamical changes in the velocity spread have to be taken into account for helium gas that is initially hot, when Doppler shifts relative to the solar emission line are significant; the present solutions being the thermal approximations to the distribution function reveal the appropriate radial temperature as a function of space. 相似文献
17.
Formation of the FeI 5324.19 line in the sun and theoretical calibration of solar magnetic telescope
《Chinese Astronomy and Astrophysics》1982,6(2):129-136
Using the Unno-Beckers equations and the Rnnge-Kutta method with variable steplength, we calculated the formation in a magnetic field of the FeI λ 5324.19 line in the solar photosphere, sunspot penumbra and umbra, and determined various theoretical calibration parameters for the magnetic and radial velocity fields. These parameters for the transverse and velocity fields have good linearity and stability and adequate sensitivity, making the line very suitable for the study of solar active regions. When observing the transverse field, the filter should best be placed 0.10 – 0.11 A away from the line centre. The calibration is rather complicated when magneto-optical effects are considered. Temperature sensitivity effects of this line should not be serious. 相似文献
18.
Numerous studies in the past few years have analyzed possible effects of planetary migration on the small bodies of the Solar System (mainly asteroids and KBOs), with the double aim of explaining certain dynamical structures in these systems, as well as placing limits on the magnitude of the radial migration of the planets. Here we undertake a similar aim, only this time concentrating on the dynamical stability of planetary satellites in a migration scenario. However, different from previous works, the strongest perturbations on satellite systems are not due to the secular variation of the semimajor axes of the planets, but from the planetesimals themselves. These perturbations result from close approaches between the planetesimals and satellites.We present results of several numerical simulations of the dynamical evolution of real and fictitious satellite systems around the outer planets, under the effects of multiple passages of a population of planetesimals representing the large-body component of a residual rocky disk. Assuming that this component dominated the total mass of the disk, our results show that the present systems of satellites of Uranus and Neptune do not seem to be compatible with a planetary migration larger than even one quarter that suggested by previous studies, unless these bodies were originated during the late stage of evaporation of the planetesimal disk. For larger variations of the semimajor axes of the planets, most of the satellites would either be ejected from the system or suffer mutual collisions due to excitation in their eccentricities. For the systems of Jupiter and Saturn, these perturbations are not so severe, and even large migrations do not introduce large instabilities.Nevertheless, even a small number of 1000-km planetesimals in the region may introduce significant excitation in the eccentricities and inclinations of satellites. Adequate values of this component may help explain the present dynamical distribution of distant satellites, including the highly peculiar orbit of Nereid. 相似文献
19.
Alton P. Mayo 《Celestial Mechanics and Dynamical Astronomy》1979,19(4):317-333
Analytic expressions are derived for the perturbation of planetary orbits due to a thick constant density asteroid belt. The derivations include extensions and adaptations of Plakhov's analytic expressions for the perturbations in five of the orbital elements for closed orbits around Saturn's rings. The equations of Plakhov are modified to include the effect of ring thickness and additional equations are derived for the perturbations in the sixth orbital element, the mean anomaly. The gravitational potential and orbital perturbations are derived for the asteroid belt with and without thickness, and for a hoop approximation to the belt. The procedures are also applicable to Saturn's rings and the newly discovered rings of Uranus.The effects of the asteroid belt thickness on the gravitational potential coefficients and the orbital motions are demonstrated. Comparisons between the Mars orbital perturbations obtained using the analytic expressions and those obtained using numerical integration are discussed. The effects of the asteroid belt on the Earth based ranging to Mars are also demonstrated. 相似文献
20.
We consider radial periodic perturbations of a central force field and prove the existence of rotating periodic solutions, whose orbits are nearly circular. The proof is mainly based on the Implicit Function Theorem, and it permits to handle some small perturbations involving the velocity, as well. Our results apply, in particular, to the classical Kepler problem. 相似文献