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121.
Valentin V. Kalenichenko 《Astrophysics and Space Science》2000,274(3):489-502
The electronic version of an extensive catalogue of the results of the fireball physics inverse problem solution for the precise
observational data of the Prairie Network Fireballs (DTHM-values) obtained by local-ballistic method of a variably-sliding
path-segment contains a set of the physical parameters for the 480 fireball images of the 248 cosmic body entries into the
Earth's atmosphere (PNVK-values). The parameters are: the fireball velocity with the corresponding values of the mass to cross-section
area ratio for the fireball-generating body a teach measured point of the fireball path, the ablation factor and the ratio
of the luminous fireball energy to the drag work for the body in the Earth's atmosphere using a factor inversely proportional
to the density of the body. The catalogue of all PNVK-values, about 3.1 Mbytes in ASCII is accessible from ftp://ftp2.mao.kiev.ua/pub/astro/pnvk,
files pnvk.cat and pnvks.cat
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
122.
We present the results of our systematic study of the long-period orbital evolution of all of the outer Saturnian, Uranian, and Neptunian satellites known to date. The plots of the orbital elements against time give a clear idea of the pattern of the orbital evolution of each satellite. The tabular data allow us to estimate the basic parameters of the evolving orbits, including the ranges of variation in the semimajor axes, eccentricities, and ecliptical inclinations as well as the variation periods and mean motions of the arguments of pericenters and the longitudes of the nodes. We compare the results obtained by numerically integrating the rigorous equations of the perturbed motion of the satellites with the analytical and numerical-analytical results. The satellite orbits with a librational pattern of variation in the arguments of pericenters are set apart. 相似文献
123.
V. P. Kozhevnikov 《Astrophysics and Space Science》2013,346(2):463-475
We report results of extensive photometry of the suspected cataclysmic variable FBS 1220+753. The observations were obtained over 28 nights in 2010, 2011 and 2012. The total duration of the observations was 160 h. We clearly detected the highly coherent oscillation with a period of 1.0712887±0.0000013 h and a stable semi-amplitude of 0.03 mag. In a time scale of years, the oscillation period is very stable (dP/dt<(4.1±1.4)×10?10). The light curves of FBS 1220+753 show no obvious flickering. The significant brightness changes on large time intervals are also absent. Therefore, it is unlikely that FBS 1220+753 is a cataclysmic variable. The period is compatible with oscillations seen in δ Sct variables. But its high stability and the unchangeable oscillation amplitude suggest that the oscillation cannot be caused by multiperiodic stellar pulsations. The average pulse shape of the oscillation is very sinusoidal with slightly sharper maxima compared with minima, but it is somewhat changeable from year to year. The light curves obtained in 2011 and folded with the doubled oscillation period reveal that the adjacent oscillation cycles have slightly different depths of the minima and different steepness of the rise and decline. This behaviour resembles the behaviour of the binary subdwarf–white dwarf systems, in which the variability is caused by ellipsoidal variations. However, the folded light curve obtained from the data of 2010 reveal nearly equal shapes of the adjacent oscillation cycles, and this does not conform to such an interpretation. Thus, the nature of the oscillation seen in FBS 1220+753 remains puzzling. To solve this puzzle, detailed spectroscopic observations are needed. 相似文献
124.
P. P. Malovichko 《Kinematics and Physics of Celestial Bodies》2007,23(5):185-190
Current instability of Alfvén waves in coronal loops is considered. Such a mechanism of Alfvén wave generation is shown to be very efficient, and it can give rise to low-frequency perturbations even in the case of very weak currents, thus fostering the reconnection of magnetic fields and development of a flare. The low-frequency turbulence which arises in the process can be favorable to the heating and acceleration of particles. 相似文献
125.
U-Pb (SHRIMP-II) isotopic dating has been conducted for zircons of the ash sediments of the Ust’-Suifun Suite, which was the
final stage of Late Cenozoic explosive volcanism in Southwest Primorskii krai. These pyroclastic units are widespread within
sediments that fill in Cenozoic depressions including large coalfields. The concordant dates (23.7–24.6 Ma) are in line with
the results of the K-Ar determinations for volcanic tephra (23.6–27.1 Ma) and correspond to the beginning of the active phase
of spreading and taphrogenesis in the neighboring Trench of the Sea of Japan. These processes started as early as the Eocene
and are reflected in the continental vicinity with the formation of riftogenic depressions and the occurrence of a peculiar
gas volcanism. 相似文献
126.
M. V. Samokhin 《Astrophysics and Space Science》1993,203(1):109-120
The flow of the current along the magnetic field lines in the thin plasma directed opposite to the electric field is considered. The particles moving to the equatorial plane are supposed to have mirror points above the region of absorption (the ionosphere) and the particles moving to the ionosphere are supposed to have mirror points below the region of absorption. The current, therefore, flows. The functions of the distribution of the electrons and ions are considered to be mono-energetic. The energies of the electrons and the ions and their densities on the boundary of absorption are estimated for the potential difference and for the current density which are typical for the auroral field lines. 相似文献
127.
Ostapchuk A. A. Kocharyan G. G. Morozova K. G. Pavlov D. V. Gridin G. A. 《Izvestiya Physics of the Solid Earth》2021,57(5):659-670
Izvestiya, Physics of the Solid Earth - Abstract—Granular media determine the dynamics of many natural systems including faults in the Earth’s crust. The paper addresses the laboratory... 相似文献
128.
V. A. Brumberg 《Celestial Mechanics and Dynamical Astronomy》2004,88(2):209-225
For numerical integration of the geocentric equations of motion of Earth satellites in the general relativity framework one may choose now between rather simple equations involving in their relativistic dynamical part only the Earth-induced terms and very complicated equations taking into account the relativistic third-body action. However, it is possible quite easily to take into account the relativistic indirect third-body perturbations and to neglect much lesser direct third-body perturbations. Such approach is based on the use of the Newtonian third-body perturbations in geocentric variables with expressing them in the relativistic manner in terms of the barycentric arguments. Together with it, to extend the known results for the spheroid model of the Earth, the Earth-induced terms are treated in great detail by including the non-spin part of the Earth vector-potential and the Earth triaxial non-sphericity.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
129.
We give the results of photographic, photoelectric, and spectral observations of the flare star PP Ori. The 109 photographic observations used, which were obtained on the 40 Schmidt telescope of the Byurakan Observatory over a period of about 20 years, and four spectra obtained on the same telescope with a4° objective prism show no variation in brightness. Photoelectric observations in the UBVR bands using the 50cm and 60cm telescopes of the high-altitude Maidanak station of the Tashkent Astronomical Institute in 1987 and 1989 give grounds for suspecting a variation in brightness much larger than observational errors. Spectral observations of the star PP Ori made on the 2.6m telescope of the Byurakan Observatory show weak H emission. The results of all these observations show that PP Ori is an Orion variable of spectral class K7-M0 with absolute visual magnitude7
m
5–8
m
5.Translated fromAstrofizika, Vol. 38, No. 2, 1995. 相似文献
130.
This article gives an account of the results of the U-Pb-SHRIMP study of zircons derived from gneissoid and equigranular granitoids
of the Malka Uplift of the Sredynnyi Range in Kamchatka. It was established that intrusion and crystallization of granitoids
occurred in the time interval from 76.2 ± 1.5 to 83.1 ± 2.0 Ma. The texture of zircon crystals suggests their magmatic origin.
The obtained data reliably confirm that granite formation and emplacement of the recently formed continental crust in Kamchatka
took place in the Late Cretaceous (Campanian). 相似文献