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931.
A new formulation is presented for the perturbed Lambert problem. The formulation employs the variation-of-parameters method in the KS transformed state space to determine perturbations of a Keplerian Lambert solution. The approach is universal (in that its validity is not restricted to a particular energy domain). For the case of the second zonal harmonic (oblateness) perturbation, first order perturbations are carried out entirely analytically; non-iterative corrections are determined through solution of a pair of algebraic equations. For more general perturbations, numerical quadratures are required. 相似文献
932.
O.A. Troshichev V.A. Gizler I.A. Ivanova A.Yu. Merkuryeva 《Planetary and Space Science》1979,27(12):1451-1459
The distant effects of the field-aligned currents (FAC) observed by TRIAD are computed for conditions of low and moderate activity. The systems of total ionospheric currents (both Hall and Pedersen) generated by corresponding FAC are also examined and the contribution of the distant effects and the ionospheric currents into the total equivalent current system is estimated. The conclusions are as follows. In cases of low magnetic activity the magnetic effects produced by Pedersen currents are mainly cancelled by the FAC distant effect in accord with Fukushima's theorem. In cases of moderate activity when the zone of high ionospheric conductivity and the two-sheet FAC structure are present the FAC distant effect is too small to cancel the effect of Pedersen currents. For these conditions the system of total ionospheric currents shows the best correspondence with the experimental equivalent current system. Effects produced by the IMF azimuthal component are also analysed. 相似文献
933.
We have analysed the 1978 UBV photoelectric observations of the short-period (RS CVn type) binary system RT And, using the rectifiable methods of Russell and Merrill (1952) and Kitamura (1965). The primary minimum is a transit. The solutions allow us to classify the system as a detached one, but a certain disagreement results with respect to solutions of previous epochs. A graphical test of the reliability of the solution is given. 相似文献
934.
A comparison of soft X-ray pictures of the Sun (S-054 experiment of Skylab) with K-line spectroheliograms (Mount Wilson) shows that the X-ray bright points tend to emerge randomly throughout the Ca network pattern. However, all those bright points that developed into active regions emerged at the boundaries of network cells. This suggests that the magnetic flux of active regions comes from greater depths in the convection zone than the shallow flux that gives rise to the random emergence of bright points.Also Physics Department, C-011, University of California at San Diego, La Jolla, Calif., U.S.A. 相似文献
935.
A spectrum scanning Stokes polarimeter 总被引:1,自引:0,他引:1
936.
Lowell's value for the mass of Planet X was about seven times that of the Earth. Postdiscovery determinations of the mass of Pluto from analysis of the observed motions of Uranus and Neptune reduced this value to about one Earth mass. More extended analyses in the past 10 years have lowered this value to about one-tenth of an Earth mass. The mass so derived, however, fails to agree by a factor of 50 with that determined from the motion of the newly discovered satellite Charon. The discrepancy may arise from unmodeled effects in the motions of the outer planets. 相似文献
937.
C. L. Goudas M. leftaki E. G. Petsagourakis 《Celestial Mechanics and Dynamical Astronomy》1989,47(1):1-14
The zero-velocity curves and surfaces created by two parallel or antiparallel magnetic dipoles moving on concentric circles are computed. It is found that for all combinations of values of the mass parameter µ and the ratio of the magnitudes of the magnetic moments of the two dipoles, there exist closed regions inside of which charged particles are permanently trapped. 相似文献
938.
Nonlinear axisymmetric oscillations of a warm baroclinic eddy are considered within the framework of an reduced-gravity model of the dynamics of a multilayer ocean. A class of exact analytical solutions describing pure inertial oscillations of an eddy formation is found. The thicknesses of layers in the eddy vary according to a quadratic law, and the horizontal projections of the velocity in the layers depend linearly on the radial coordinate. Owing to a complicated structure of the eddy, weak limitations on the vertical distribution of density, and an explicit form of the solution, the latter can be treated as a generalization of the exact analytical solutions of this form that were previously obtained for homogeneous and baroclinic eddies in the ocean. 相似文献
939.
报告了中、美两国在喜马拉雅山区进行的第一次深反射地震试验的结果.试验剖面南起喜马拉雅山山脊南亚东县的帕里镇,向北穿过喜马拉雅山脊的荡拉,到达康马南的萨马达.剖面长约100km.共中心点(CMP)叠加剖面上显示出:1.在地壳中部有一强反射带,向北缓倾斜下去,延长达100km以上.它可能代表了一个活动的逆冲断裂或是一条巨大的拆离带,印度地壳整体或下地壳沿此拆离层俯冲到藏南之下.2.上部地壳的反射很丰富,显示了上地壳存在着大规模的叠瓦状结构.3.下地壳的反射同相轴呈现短而有规律的分布,显示了塑性流变特征.4.在测线南部莫霍反射明显,深度达72-75km.发现南部有双莫霍层的存在.5.试验中还取得莫霍层下面32,38,48s等双程走时的多条反射,向北倾斜,反射同相轴延续较长,信息丰富,反映了上地幔的成层结构和变形特征.这些结果对印度大陆地壳整体或其下地壳俯冲到藏南特提斯喜马拉雅地壳之下,并导致西藏南端地壳增厚的观点,给予了实质性的支持. 相似文献
940.
On scans obtained with the Oxford photoelectric spectrometer, the [Ca ii] transition 4s 2S1/2-3d 2D3/2; is identified with a weak Fraunhofer line. It is argued that the strength of the line is consistent with the abundance of calcium which is derived from the permitted lines of Ca i and Ca ii. 相似文献