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941.
942.
We present result for the mass of (1) Ceres, determined from its close encounter with asteroid (5303) Parijskij. Gravitational
effects of (1) Ceres on the motion of (5303) Parijskij is the largest found so far. Also, we analyzed available data of close
encounter with (7298) 1992 WM5. 相似文献
943.
Time evolution of the interplanetary dust particle under the action of the solar electromagnetic radiation (Poynting-Robertson effect) is investigated. Evolution of the initially circular orbit in terms of the orbital elements present in the standard equations for their secular changes is considered. It is pointed out that the osculating eccentricity is practically constant during the motion in spite of generally accepted opinion that the standard equations for the secular changes of orbital elements represent time evolution of the osculating elements. 相似文献
944.
945.
The apparent yearly precession of the solar globe has been defined and described in some detail. Line-of-sight velocities less than ±18 m s-1 occur at the solar disk. The importance of the line-of-sight component of the precession in general, and as a test velocity in contemporary photospheric velocity research is pointed out. 相似文献
946.
Celestial Mechanics and Dynamical Astronomy - Differences among the Earth gravity field models, which were (in Klokočník and Pospíšilová, 1981) expressed as dispersions of... 相似文献
947.
Pavel Voráček 《Astrophysics and Space Science》1979,65(2):415-418
In this paper the expression for the magnitude of the so-called induced force, acting on a mass particle, is deduced. The origin of this force is causally connected to the increase of the rest mass of the particle in the gravitational field. 相似文献
948.
Petr Vaníček 《Astrophysics and Space Science》1971,12(1):10-33
The concept of spectral analysis using least-squares is further developed to remove any undesired influence on the spectrum. The influence of such a systematic noise can be eliminated without the necessity of knowing the magnitudes of the noise constituents. The technique can be used for irregularly spaced as well as equidistantly spaced data. The response to random noise is found to be constant in the frequency domain and its expected level is derived. Presence of random noise in the analyzed time series is shown to transform the spectrum merely linearly. Examples of applications of the technique are presented. 相似文献
949.
Pavel Voráček 《Astrophysics and Space Science》1979,65(2):397-413
From the general theory of relativity a relation is deduced between the mass of a particle and the gravitational field at the position of the particle. For this purpose the fall of a particle of negligible mass in the gravitational field of a massive body is used. After establishing the relativistic potential and its relationship to the rest mass of the particle, we show, assuming conservation of mass-energy, that the difference between two potential-levels depends upon the value of the radial metric coefficient at the position of an observer. Further, it is proved that the relativistic potential is compatible with the general concept of the potential also from the standpoint of kinematics. In the third section it is shown that, although the mass-energy of a body is a function of the distance from it, this does not influence the relativistic potential of the body itself. From this conclusion it follows that the mass-energy of a particle in a gravitational field is anisotropic; isotropic is the mass only. Further, the possibility of an incidental feed-back between two masses is ruled out, and the law of the composition of the relativistic gravitational potentials is deduced. Finally, it is shown, by means of a simple model, that local inhomogeneities in the ideal fluid filling the Universe have negligible influence on the total potential in large regions. 相似文献
950.
Pavel Voráček 《Astrophysics and Space Science》1989,161(1):165-166
A possible solution is presented of the issue of the ascertained zero cosmological constant in connection to its high value expected from the existence of vacuum energy density. The answer should be that in the metric space the virtual particle pairs arise together with a correlated negative quantum energy defect, so that the total mass-energy of every pair precisely equals zero. The various observed phenomena can still be explained. 相似文献