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941.
Dynamic spectra of a Jovian non-Io-A storm recorded simultaneously by the Voyager 1 spacecraft and by the Kiiminki radio spectrograph are compared. It seems that the emission beam of the storm co-rotates with the planet and has a sloped leading edge, in accordance with the result of Maeda and Carr (1984). 相似文献
942.
943.
The classical problem of the critical inclination in artificial satellite theory has been extended to the case when a satellite may have an arbitrary, significant mass and the rotation momentum vector is tilted with respect to the symmetry axis of the planet. If the planet’s potential is restricted to the second zonal harmonic, according to the assumptions of the main problem of the satellite theory, two various phenomena can be observed: a critical inclination that asymptotically tends to the well known negligible mass limit, and a critical tilt that can be attributed to the effect of transforming the gravity field harmonics to a different reference frame. Stability of this particular solution of the two rigid bodies problem is studied analytically using a simple pendulum approximation. 相似文献
944.
945.
946.
947.
The eclipsing binary AV Hya has been observed photoelectrically inU, B andV filters on 15 nights. The primary eclipse appeared to be total with a totality of 23 min duration. A modified period of 0d.6 834 062 has been obtained. Geometrical elements could only be determined for partial transit case. 相似文献
948.
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
949.
The seasonal variation of the nocturnal average intensity, and the typical variation of the sodium airglow intensity during the night have been deduced, using a data set that has been accumulated over a period of 5 years. The maximum intensity, which occurs at the equinoxes, is about 2–3 times as large as the intensity during winter, when the intensity of the D2 line is about 30 R. The nocturnal variation is symmetrical about midnight, where the intensity is some 30% less than just after (before) dusk (dawn) values. 相似文献
950.