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1.
, ( ). n
=3–5, T
e
=4T
b
(1 + ), - ( ) ,T
b
- . , . , . W
H
, ,n
=3,
=1. n
=3–5(E), (E) , , = 1 – (), |()| < 1, |(E)| < 1. 3 273. 相似文献
2.
The technique of the general planetary theory has been proposed for constructing a theory of motion of the Moon. This method enables us to elaborate the consistent theory of motion of the principal planets and the Moon, which is of particular importance for determining planetary perturbations in lunar motion. As an initial approximation for lunar motion, an intermediate orbit generalizing the Hill's variational curve has been built. This orbit includes all solar and planetary inequalities independent of eccentricities and inclinations of the Moon, Sun and planets. In calculating this orbit, the motion of the principal planets in quasi-periodic intermediate orbits has been taken into account. This solution was produced with the aid of the Universal Poissonian Processor (UPP) elaborated in the Institute for Theoretical Astronomy (Leningrad).Proceedings of the Conference on Analytical Methods and Ephemerides: Theory and Observations of the Moon and Planets. Facultés universitaires Notre Dame de la Paix, Namur, Belgium, 28–31 July, 1980. 相似文献
3.
, . : , . , . . ( ) . . . HZ Her=Her X1, . . , . , ., hv 15–30 . , . Sco X1 . 相似文献
4.
P. J. Message 《Celestial Mechanics and Dynamical Astronomy》1982,26(1):25-39
For the planetary case of the gravitationaln-body problem in three dimensions, a sequence of Lie series contact transformations is used to construct asymptotic series representations for the canonical parameters of the instantaneous orbits in a Jacobi formulation. The series contain only periodic terms, the frequencies being linear combinations of those of the planetary orbits and those of the secular variations of the apses and nodes, and the series are in powers of the masses of the planets in terms of that of the primary, and of a quantity of the order of the excursions of the eccentricities and inclinations of the orbits. The treatment avoids singularities for circular and coplanar orbits. It follows that the major axes are given by series of periodic terms only, to all orders in the planetary masses.Proceedings of the Conference on Analytical Methods and Ephemerides: Theory and Observations of the Moon and Planets. Facultés universitaires Notre Dame de la Paix, Namur, Belgium, 28–31 July, 1980. 相似文献
5.
6.
Г. А. Гурзадян 《Astrophysics and Space Science》1979,64(1):3-23
2800 Mgii (. 1). (N
+/N
11000) , , (N
+/N
110). , . —, , . — . : ; 0.002 1 , 0.1 ; () 100 –3; ; ; , 10
; 10–4
1
. 2800 Mgii . 相似文献
7.
The effect of small perturbations and in the coriolis and the centrifugal forces respectively on the stability of the triangular points in the restricted problem of three bodies with variable mass has been studied. It is found that the range of stability of triangular points increases or decreases depending upon whether the perturbation point (, ) lies in one or the other of the two parts in which the (, ) plane is divided by the line J8–J9=0 where J8 and J9 depend upon , the constant due to the variation in mass governed by Jeans' law. 相似文献
8.
- . . , . , . 相似文献
9.
, () , , ( =2) , . (, , ). ( =0,5) . 相似文献
10.
. - . . , . - . - , , , -. ., , .
English translation will appear in the next issue ofAstrophys. Space Sci.
Receipt delayed by postal strike in Great Britain 相似文献
The structure of rotating magnetic polytropes is considered in Roche approximation. Investigation of the influence of poloidal as well as toroidal magnetic fields on the conditions of the beginning of matter outflow due to rotational instability is carried out. The influence of the turbulent convection and twisting of magnetic force-lines on the time of smoothing of differential rotation is considered. The estimate of the magneto-turbulence energy generated by differential rotation is presented. Both maximum possible energy output and duration of the quasi-statical evolution phase up to the appearance of hydrodynamic instability due to the effects of general relativity are calculated for supermassive magnetic polytropes of index three with uniform or differential rotation. The radius-mass relation is obtained for supermassive differentially-rotating magnetic polytropes referring to the longest part of the quasi-statistical evolution stage; some consequences are pointed out, including the period-luminosity relation.The evolution of the considered models of supermassive rotating magnetic polytropes with different character of rotation and different geometry of a magnetic field is discussed.The results obtained are summarized in the last section.
English translation will appear in the next issue ofAstrophys. Space Sci.
Receipt delayed by postal strike in Great Britain 相似文献
11.
We study the so-called inverse planetary problem (i.e., given the distances from the centre, masses, and radii of, say, three planets of a planetary system, find the optimum polytropic index, mass, and radius of their star, and also other quantities of interest, which depend either explicitly or implicitly on the foregoing ones, e.g., central and mean density, central and mean pressure, central and mean temperature, etc.) for the system of satellites of Jupiter. In particular, Jupiter is considered as star and its satellites as planets of a proper planetary system, which is then treated numerically on the basis of the so-called global polytropic model, developed recently by the first author. 相似文献
12.
, . , . . , (, ). , ( , ). 相似文献
13.
В. А. Гаген-Торн 《Astrophysics and Space Science》1980,73(2):279-294
J 287 1972–1976. , . . J ( ), () . (0=80°) . J 287 ¶ . p=42.8%, 0=101°. (50%). 相似文献
14.
, . , , . . . . . , , . 相似文献
15.
A. A. Stepanian B. M. Vladimirsky Yu. I. Neshpor V. P. Fomin 《Astrophysics and Space Science》1975,38(2):267-282
The results of the observations to search gamma-ray sources with the energy greater than 2×1012 eV, which were made in Crimean Astrophysical Observatory during the years 1969–73 are presented. A technique of the detection of the EAS Cerenkov flashes was used.The quality of the data obtained is analysed. The criteria for the selection of the data free from meteorological variations are considered.It was shown that two objects, namely, Cyg X-3 and Cas -1, may be the sources of high-energy gamma quanta. It is probable that the object with the coordinates =05h15m, =+1° is the source of gamma-rays as well. An unidentified object Cas -1 is variable: gamma-ray flux was observed twice — in Sepember–October 1971 and in December 1972. It is possible that the flux from Cyg X-3 has a period of 4.8 hr.
I I , I I , - >2.1012 . I . I , I I, I ., - -1 Cyg -3- -I . , =0515 ·=+1° -.I -1 I: I J I- - 1971 1972 . Cyg -3, , - T=4.8 .相似文献
16.
A. M. I. Osman 《Astrophysics and Space Science》1985,116(2):299-311
Surface photometry of the UV continuum galaxy NGC 838 has been carried out in theB, V system using photographic plates obtained with the 74 Kottamia telescope, Egypt. Isophotes, luminosity profiles, integrated photographic magnitudes, effective diameters and other photometric parameters are derived.The photoelectrically calibrated total apparent magnitudes areB
T
=13.57 with maximum diameters 1.57×1.34 (at threshold
m
=27.7 mag.//) andV
T
=12.91 with maximum diameters 1.54×1.32 (at threshold
m
=27.7 mag./). The integrated colour index(B–V)
T
=0.66 and the effective surface brightness
e
(B=19.0 mag./) and
e
(V=19.7 mag./. The major axis is at position angle =85°±1°.The nucleus of NGC 838 is quite blue (integrated colour(B–V)=0.41 forr
*<0.1) compared to normal galaxies while the colour becomes redder from the nucleus outwards. The UV excess, H emission and radio continuum emission previously observed from this galaxy by other investigators may be attributed to a recent burst of star formation in the nucleus of the galaxy of duration slightly greater than 2×107 yr. 相似文献
17.
Eugenio E. Mendoza V. 《Astrophysics and Space Science》1990,171(1-2):157-160
We present observational data in the (16)(9)(25)-photometric system for 11 Wolf-Rayet stars and 7 planetary nebulae. The results show anomalous (16)(9)-indices for these emission objects. Six W-R stars show possible variations in the strength of the HeII line at 6560 Å, perhaps none in the strength of the HeI line at 10830 Å. In spite of these misconstrued (16) and (9)-indices, most WC stars are separated from WN stars in the (16)(9)-array; and PN, in this diagram lie far apart from all kind of stellar objects. The results, yielded by the (25)-index, indicate that the HeI and HeII lines at 10830 Å and 10124 Å, respectively, are probably well suited for photometric examination in W-R stars, PN and other peculiar objects.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain. 相似文献
18.
Г. И. Ширмин 《Celestial Mechanics and Dynamical Astronomy》1975,11(4):483-515
1937 - (, 1938). , , , , . , . . (, 1938), , . - (, 1938; Szebehely, 1967)., , . . - (, 1938), . — — . , , . , . . , . , , . . (, 1944). , .
In 1937, the Celestial Mechanics and Cosmogony section of the Sternberg State Astronomical Institute undertook the task of evaluating the Gylden-Moulton hypothesis on the origin of the Gegenshein from the standpoint of celestial mechanics. That investigation, which the authors themselves considered preliminary, contains nonetheless a series of important results. For example, G. N. Duboshin showed that in the planar, circular, restricted three-body problem, periodic motion of finite amplitude in the neighborhood of a collinear libration point is unstable according to Lyapunov's criterion both in the proper and in the orbital sense. The latter result is incompatible with the above named hypothesis, and thus appears as one of the serious objections among the many known negative conclusions relative to the existence of the Gylden-Moulton cluster.Unfortunately, most of the specific problems which arose in the above named research have not been considered since. One of these, the problem of the stability of three-dimensional periodic orbits in the neighborhood of a collinear libration point is solved in the present paper, within the limits of the three-dimensional, circular, restricted, three-body problem. Major attention is given to the investigation of stability in the orbital sense, since in the proper sense all orbits are unstable according to Lyapunov theory. It is shown that in order to resolve the question of stability, it is sufficient to consider the equations in their variational form. Analysis of the roots of the corresponding characteristic equations determines the orbital stability of planar and three-dimensional solutions, which later can be confirmed by calculation of the characteristic exponents appearing in the periodic solutions of the N. A. Artemiev method. Finally, the possibility of conditional stability in the linear approximation is proved.相似文献
19.
Present Observational Status of the Intermediate Mass Stars: δ Sct Stars, γ Dor Stars and roAp Stars
D.W. Kurtz 《Astrophysics and Space Science》2003,284(1):29-36
The present observational status of the Sct stars, Dor stars and roAp stars is discussed. The Sct stars are the most intensively observed of the three groups, but it has become clear that there are severe problems in extracting asteroseismic information from them. Dozens of frequencies are observed, but hundreds of frequencies are predicted from the models; unique matches of observation and theory still elude us. The Sct stars are observationally complex – some recent `best case' campaigns are discussed. It is possible that substantial observational advances for Sct stars may need to await upcoming satellite missions. New Dor stars are beingdiscovered frequently, and new behaviour is being found for them. They constitutean observationally young field. Their pulsational frequency range is being expanded, their position in the HR diagram is becoming better known (but is yet to be fully constrained), and the possibility exists of hybrid Dor – Sct stars that have greatasteroseismic promise, although it is clear such stars are rare, if they do exist. It has been observationally challenging to extract more than a fewfrequencies for any Dor star so far. Exciting spectroscopic discoveries of new behaviour in roAp stars promise unprecedented information about the structure of the peculiar atmospheres ofthose stars – pulsation amplitude and phase in 3D, magnetic field structurein 3D, abundance stratification in 3D, realistic T- for the most peculiarstars – as well as entirely new information about the interaction of pulsation,rotation and magnetic fields. Recent theoretical work has led to new understandingof the previously inexplicable frequency spacing of HR 1217 with new Whole Earth Telescope observations supporting this theory. An `improved oblique pulsator model' has been developed in which the pulsationaxis is not the magnetic axis; this model has passed several observationaltests and new ones are being devised to examine it further. 相似文献
20.
M. Sh. Gigolashvili 《Solar physics》1984,93(2):317-324
A brief quantitative review of the determination of the chemical composition of the Sun and stars is given. The method of estimation of the total amount of hydrogen atoms in a prominence is considered.The values of relative abundances of some infrequent elements in the solar atmosphere are refined using metal emission lines in the spectrum of a quiescent prominence. The most probable values of relative abundances for itrium Y1×10–9, zirconium Zr2×10–9, and scandium Sc3.8×10–9 are derived. 相似文献