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1.
, , . . ( I), ( II). I , () . -, . , , (R/R i)2/3, R/R i- . ( II) . , . , , , . , . , , . , , - , , . , , , , . , . . . 1969 .  相似文献   

2.
The data of the line series CH3CN 8(K) – 7(K) K = 0 – 7 and line CS J = 3 – 2 were taken simultaneously. At beam size of 16 the emissions of CH3CN and CS have a common center position located near IRc2 with deviations -8 and 5. The observed data show that in Orion KL core the integrated intensities of the two species have double peaks separated by a space of 14. The 2-dimension Gaussian fitting plots (FWHM) are ellipses ofD maj = 26 andD min = 22 for CH3CN 8(K) – 7(K) K = 3 – 6 andDmaj = 39 Dmin = 31 for CS J = 3 – 2 at a distance about 450 pc. Towards the multiple line emission region of CH3CN 8(K) – 7(K) K = 3 – 6, using a simplified very large velocity gradient model to solve the statistical equilibrium and radiative transfer equations, we find to fit the observed results, the optimum physical parameters and kinetic temperatureT k 120 K, densityn(H a) 1.2 × 105 cm–3, velocity gradientV gr 92 km s–1 pc–1 and the local abundance of CH3CNF ab 3 × 10–8. However towards the region of single line emission of CS J = 3 – 2 we have to use LTE and the optical thin approximation on the assumption ofT k= 120 K to obtain the lower limits of column density and then, an averaged abundance of CS of 6 × 10–8.  相似文献   

3.
The equation for the two-particles cosmic-ray distribution function is derived by means of the Boltzmann kinetic equation averaging. This equation is valid for arbitrary ratio of regular and random parts of the magnetic field. For small energy particles the guiding-center approximation is used. On the basis of the derived equation the dependence between power spectra of cosmic-ray intensity and random magnetic field is obtained. If power spectra are degree functions for high energy particles ( 10 GeV nucleon–1), then the spectral exponent of magnetic field lies between and –2, where is the spectral exponent of cosmic-ray power spectra. The experimental data concerning moderate energy particles are in accordance with =, which demonstrates that the magnetic fluctuations are isotropic or cosmic-ray space gradient is small near the Earth orbit.  相似文献   

4.
We compute classical white-dwarf models distorted by magnetic field and differential rotation. In the computations we implement a complex-plane strategy and a multiple-partition technique, which have been developed recently by the first author.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   

5.
Preliminary results of polarization measurements at three solar flares of July 5 and 6, 1974, are given. The measurements were performed at h 15 keV with Thomson-scattering polarimeter on the Intercosmos 11 satellite.At the decay phase of the flare on July 5 we obtained P = 3.4–5.0%, which did not exclude some contribution from non-thermal processes. At the flares of July 6 we found P =1.0–1.9% and P = 0.1–2.0%, respectively: neither value exceeds the level of statistical fluctuations.Presented at XVIII COSPAR Meeting (VARNA, May–June 1975), contribution III.B.2.9.  相似文献   

6.
Johann Heinrich Lambert, a Swiss-German scholar, was counted among the most famous men of his time. Being an autodidact and without formal university studies, he won access to the modern sciences, in particular to philosophy, mathematics, astronomy and physics; and indeed he was most successful in all these fields. In the area of mathematics, for example, he made contributions to the theory of irrational numbers (continued fractions), to the problem of parallel lines and non-Euclidian geometry, to trigonometry (group-theoretical formulation of Nepper's rule), the foundations of the perspective, he gave a proof for the irrationality of e and and moreover some remarkable indications for their transcendency, to mention only a few. In the field of astronomy, he made contributions not only to the foundations of photometry but also to the orbital determination of planets and comets, which culminated in Lambert's Theorem. This, as well as his Cosmologische Briefe (with which he made a contribution to the structure of the world parallel to the Kantian view) is the subject matter of the following report. Even in philosophy Lambert kept pace with Kant (Criterium veritatis, 1761 when he said: Wir wissen, dass Gestalt und Grösse vom Orte umabhängige Bestimmungen sind.).
Zusammenfassung Johann Heinrich Lambert, ein deutsch-schweizer Wissenschaftler, gehörte zu den berühmtesten Männern seiner Zeit. Er hat als Autodidakt ohne Studium an einer Hochschule sich den Zugang zu den modernen Wissenschaften, insbesondere zue Philosophie, zur Mathematik, zu Astronomie und Physik geschaffen und auf diesen Gebieten Fortschrittliches geleistet. Auf dem Gebiete der Mathematik z.B. waren es seine Beiträge zur Theorie der Irrationalzahlen (Kettenbrüche), zum Problem der Parallellinien und der nichteuklidischen Geometrie, zur Trigonometrie (gruppentheoretischer Ansatz für die Neppersche Regel), die Begründung der Perspektive, Beweis der Irrationalität von e und mit Ansätzen zum Nachweis ihrer Transzendenz, um nur einiges herauszuheben. Auf dem Gebiete der Astronomie waren es neben seinen Grundlagen für die Photometrie seine Beiträge zur Bahnbestimmung von Planeten und Kometen, die er mit dem nach ihm benannten Lambertschen Theorem krönte. Darüber und über seine Cosmologischen Briefe, mit denen er einen Beitrag zur Struktur der welt parallel zu der von Kant gegeben hat, wird im folgenden ausführlich gehandelt. Auch in der Philosophie war er im Gleichschritt mit Kant (Criterium veritatis 1761 mit dem Ausspruch: Wir wissen, daß Gestalt und Größe vom Orte unabhängige Bestimmungen sind.).

Proceedings of the Sixth Conference on Mathematical Methods in Celestial Mechanics held at Oberwolfach (West Germany) from 14 to 19 August, 1978.  相似文献   

7.
The velocity field in a large complex sunspot is investigated in Fe i 6302.5 Å and in H with a spatial resolution of about 2.5. The Evershed flow is almost parallel to the solar surface. For the inclination angle between the velocity and the horizontal = 4.4°±1.3° is estimated; = 11° is the definite upper limit.  相似文献   

8.
Interstellar reddening, the ratio [Fe/H], effective temperatures, surface gravities, and masses for twelve clump stars at the blue end of the giant branch and for seven non-clump red giant members in NGC 7789 have been determined from existingUBV andDDO photoelectric data. For the metal abundance and helium content of the clump stars we foundZ0.01 andY0.38, respectively. The masses of the red giants are found to be higher than those of the clump stars. On average, the masses of the clump stars are about half of the turnoff point mass. We conclude that the clump stars could have undergone mass loss before reaching their helium core burning phase of evolution. This conclusion arises from an analysis of the several sources entering our mass determination.  相似文献   

9.
Abstrakt The Kle search programme for minor planets using 0,63m Maksutov camera of Kle Observatory was begun in 1977 as a long-term project continuing up to the present day. The discovery frequency according to seasons in the year shows multiple differences between particular months.The comparison with the number of observing nights and obtained search plates; weather conditions and other influences will be discussed. The Kle minor planet discovery frequency also will be compared with the data base of all numbered minor planets.  相似文献   

10.
The restricted problem of the motion of a point of negligible mass (asteroid) in anN-planetary system is considered. It is assumed that all the planets move about the central body (Sun) along circular orbits in the same plane and the mean motions of the asteroid and the planets are incommensurable. The asteroid orbit evolution is described as a first approximation by secular equations with the perturbing function averaged by the mean longitudes of the asteroid and the planets. For small values of the asteroid orbit eccentricity an expression for the secular part of the perturbing function has been obtained. This expression holds for the arbitrary values of the asteroid orbit semiaxis which are different from those of the planet orbit radii. The stability of the asteroid circular orbits in a linear approximation with respect to the eccentricity is studied. The critical inclinations for a Solar system model are calculated.  相似文献   

11.
Reasons for interest in the origin of short-period comets and the difficulties of computing their long-term dynamcal evolution are reviewed. The relative advantages of a source region in an extended inner core of the Oort cloud or a compact comet belt just beyond the planetary system are finely balanced, and it is premature to consider the problem solved. A complication is that some comets belonging to the Jupiter family may be part of a time-dependent system, possibly the remains of a giant comet such as Chiron which could have been part of the system 104 yr ago. The origin of short-period comets plays a pivotal role in many areas of solar system science: planet formation, the source of water (possibly life) on the terrestrial planets, the cratering record on the terrestrial planets and satellites of the outer planets, and the environmental impact posed by massive bodies and their decay products in the Earth's near-space environment.  相似文献   

12.
The influence of resonance perturbations due to the gravitational field of an oblate planet on its satellite whose motion is commensurable with rotation of the planet has been investigated. It has been shown that in special case of the critical inclination or circular orbit the Lagrange equations can be integrated for all resonance terms simultaneously. The method is applied to the investigation of the motion of the 12-hour communication and navigation satellites of the Molniya and Navstar type. The computations has been performed by the use of four models of the geopotential.  相似文献   

13.
The occurrence and uniqueness of the critical inclination in satellite theory is discussed.An infinite set of canonical transformations in Hill variables are shown to exist whereby the first order secular part of the disturbing function can be changed into an alternative form. As a result of such a transformation the critical inclination can become (a)any other real or complex inclination or a function independent of the satellite's orbital inclination and (b) a function dependent on the semi-major axis, eccentricity and inclination of the satellite's orbit. It is also shown that all transformations of types (a) and (b) are only valid for short intervals of time of the order of a few satellite revolutions. Furthermore if such transformations are modified so that they become valid for greater intervals of time, then the resulting solutions in all cases containno singular divisor other than the critical inclination.It is concluded that the singularity at the critical inclination is unique and that it represents an actual physical resonance rather than something resulting from the method of solution or the type of variable used in the analysis. This conclusion is supported by numerical evidence which shows that a satellite's perigee height does suffer resonant changes when the orbital inclination is equal to the critical inclination of 63.°4.  相似文献   

14.
The formation of the gas giant planets Jupiter and Saturn probably required the growth of massive 15 Earth-mass cores on a time scale shorter than the 107 time scale for removal of nebular gas. Relatively minor variations in nebular parameters could preclude the growth of full-size gas giants even in systems in which the terrestrial planet region is similar to our own. Systems containing failed Jupiters, resembling Uranus and Neptune in their failure to capture much nebular gas, would be expected to contain more densely populated cometary source regions. They will also eject a smaller number of comets into interstellar space. If systems of this kind were the norm, observation of hyperbolic comets would be unexpected. Monte Carlo calculations of the orbital evolution of region of such systems (the Kuiper belt) indicate that throughout Earth history the cometary impact flux in their terrestrial planet regions would be 1000 times greater than in our Solar System. It may be speculated that this could frustrate the evolution of organisms that observe and seek to understand their planetary system. For this reason our observation of these planets in our Solar System may tell us nothing about the probability of similar gas giants occurring in other planetary systems. This situation can be corrected by observation of an unbiased sample of planetary systems.Paper presented at the Conference onPlanetary Systems: Formation, Evolution, and Detection held 7–10 December, 1992 at CalTech, Pasadena, California, U.S.A.  相似文献   

15.
From the growing observational evidence that binary / multiple star formation occurs prior to the pre-main sequence (Mathieu, 1992), it is clear that any theory of star formation MUST also explain binary formation. This paper details two formation mechanisms for binary / multiple stars, which occur simultaneously with protostar formation. The protostellar discs we form have masses 5 30M , diameters 200 4000 AU. The binaries / multiples have separations 400 7500 AU. The formation mechanisms were found by conducting numerical simulations of two cloud collisions, using SPH and Treecode gravity with up to 200,000 particles per calculation and a prescribed cooling equation of state.  相似文献   

16.
The diagramV - log(1 +z e ) as function of (, ) is considered for the quasars. HereV is the apparent visual magnitude,z e is the emission line redshift, and are the equatorial coordinates. Two opposite extreme spots NE and SE are observed on the sky, where the inclination of the straight line fitting the dependenceV - log(1 +z e ) is maximum and minimum. The coordinates of the centres of these extreme spots are ( NE, NE) = (282°, +42°) and ( SE, SE) = (70°, -38°) with errors 5°. A hypothesis of the Superattractor (SA) is proposed to explain such an effect. Two independent tests of this hypothesis are realized. First, the dependence or the frequency a of the absorbers in QSO spectra on (, ) is investigated. A region of the larger a is found. The coordinates of its centre are (, ) = (82°, - 10°) with error 5°. Second, the cases ofz a >z e are plotted in the Mercatorial projection (, ). The most of the casesz -z e > 0.02 are concentrated within the circle with radiusR = 34° and centre (, ) = (50°, - 15°). The both anomalous regions overlap the Southern extreme spot around SE. The SA direction is (, ) = (67°, -21°) with errors about 12°. The redshift of SA isz SA = 1.7 ± 0.3 that corresponds to the distancer SA = (3100 ± 300)h –1 Mpc for the Hubble constantH 0 = 75h kms–1 Mpc–1. The SA mass isM SA ~ 1018-1020 M . The orientation of the normal to the quasiperiodical large-scale sheet structure on the sky occurs near SA.  相似文献   

17.
The Orbiting Stellar Interferometer (OSI) is a space-based astrometric interferometer designed primarily for wide-angle astrometry. OSI is potentially capable of achieving astrometric accuracies of 1as in narrow angle (1°) astrometry. This paper discusses the implications for astrometric planet detection, specifically the detection of Earth-like planets around nearby stars. OSI has the potential to detect a limited number of planetary systems with Earths, if a number of technical problems are solved.  相似文献   

18.
The tidal field caused by the second order zonal harmonic of the gravitational field of a planet is discussed according to the fernwirkungsgesetz (principle of local action) of Weyl (1921) introducing an accurate and simple form of the gravitational potential of the planet in elliptic coordinates. It is seen that the tidal field can be described at each point as a small rotation of the local canonical frame which causes a libration and a precession of the axis of rotation of the satellites of the planet. It is also shown that at each point P, is one third of the angle between the line of force through P and the line from P to the center of mass of the planet. All the formulae obtained, to compute and , are in closed form.  相似文献   

19.
The present work is a first attempt to investigate the feasibility of the optical detection of absorption lines in the atmosphere of extrasolar planets. Two cases are considered: (1) the reflection case, where the planet is observed by imaging via the light coming from the parent star and re-emitted by the planet; and (2) the occultation case, where the planet makes a partial occultation of the star. I find only in the latter case that there are planetary configurations where the absorption lines can effectively be detected with existing or forthcoming telescopes. The discussion is basically made for the O2 A-band, which is of interest for exobiology.Paper presented at the Conference onPlanetary Systems: Formation, Evolution, and Detection held 7–10 December, 1992 at CalTech, Pasadena, California, U.S.A.  相似文献   

20.
Photoelectric observations of the light intensity from the solar crescent before and after totality were made during the eclipses of 7 March, 1970 and 26 February, 1979. Effective wavelengths were determined by interference filters of 20 nm bandwidth. To obtain the limb darkening function, the resulting intensity curves were analyzed by an extension of the method of Julius in which we take into account the actual lunar limb profile. The limb darkening function at 433 nm was obtained for the region 0.937 < sin < 0.9999. Our results are in good agreement with existing center-to-limb measurements in the region of overlap which extends to sin = 0.99. Additional data were obtained at 600 nm for 0.994 < sin < 0.9999. The curves at both wavelengths show a distinctive limb brightening effect at sin = 0.999.  相似文献   

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