Investigation of karst ice caves with the aid of remote sensing techniques     

G. S. Bordonskii  A. A. Gurulev  V. A. Obyazov  A. O. Orlov  S. V. Tsyrenzhapov 《Geography and Natural Resources》2012,33(1):87-91

Considered are some results of radio sensing conducted for the Kheetei karst ice cave in Zabaikalskii region. The cave roof was investigated by the active and passive radar techniques and infrared imaging. Revealed were sources of heat, air flows and the dislocation of rocks along the fissure under the hoar-frost layer. This technique may be used in regular measurements in order to study both changes in conditions of hollow subterranean formations and thermal processes in the environment.  相似文献   

Atmospheric circulation epochs and climate changes   总被引：5，自引：0，他引：5  

N. S. Sidorenkov  I. A. Orlov 《Russian Meteorology and Hydrology》2008,33(9):553-559

The atmospheric circulation studies allow climate changes to be diagnosed and forecasted. Variations in occurrence frequencies of the atmospheric circulation forms W, E, and C (by the Vangengeim classification) and Z, M ₁, and M ₂ (by the Girs classification), which characterize climatic conditions in most of the Northern Hemisphere, are analyzed over a period of more than 100 years. It is shown that the occurrence frequency of the forms W, C, and M ₁ continually decreased, while that of the forms E and Z increased, which indicates a significant change in atmospheric circulation in the Northern Hemisphere during the last century. The occurrence frequency of the forms C and Z demonstrates specific features at inter-decade time scales. Correlations are found between accumulated sums of anomalies of occurrence frequencies of the atmospheric circulation forms C, (W + E), Z, and (M ₁ + M ₂) and inter-decade variations of the Earth’s rotation. The causes of these relationships are discussed along with possibilities of their use for diagnosis of climatic variations in the Northern Hemisphere.  相似文献   

The orbital dust torus as an enveloping surface of a family of trajectories of isotropically ejected particles     

S. A. Orlov  K. V. Kholshevnikov 《Solar System Research》2008,42(2):91-110

Meteorite impacts onto a small satellite lead to the ejection of a regolith mass, which is much greater than the impactor mass, into cosmic space. Assume that an isotropic ejection with velocities smaller than the maximum possible velocity b took place at the time moment t ₀. Since the orbital periods are unequal, the particle trajectories will densely fill a certain domain D. The same domain will be filled after an explosion of an artificial satellite moving in a high orbit. One to three months later, the node and pericenter longitudes will be distributed over the entire circle and the domain D will become a body of revolution, a topological solid torus. We examine the domain of possible particle motion and its boundary S immediately after the impact event (an unperturbed case) and the same domain under the assumption that the initial longitudes of nodes and pericenters were already a result of considerable changes (a perturbed case). In both cases, we managed to construct the domain D and its boundary S analytically: parametric equations containing only relatively simple functions were obtained for S. The basic topologic and differential-geometric properties of S were studied completely.  相似文献   

Resonances in the three-body problem with equal masses     

A. I. Martynova  V. V. Orlov 《Astronomy Reports》2011,55(2):174-181

Numerical simulations of near-resonant motions occurring in planar rotating systems of three bodies with equal masses are presented for the cases of prograde and retrograde motions of the inner and outer pairs. The ratios n: m of the initial periods of these pairs are within 1 ≤ m ≤ n ≤ 7. It is shown that, as a rule, retrograde are more stable than prograde motions. The k loop structures oriented inwards for prograde and outwards for retrograde motions are revealed. Empirical relations between k and n are found for the main resonances n: 1 and n: 2.  相似文献   

Trajectories of bodies in zones of rapidly decaying triple systems     

A. I. Martynova  V. V. Orlov 《Astronomy Reports》2014,58(11):849-859

The general three-body problem with equal masses and zero initial velocities is considered. Zones in which the triple systems decay over short times T < 10T _cr are distinguished in the domain of the initial conditions, where T _cr is the mean crossing time for a component of the triple system. These zones form distinct families of structures. Properties of the trajectories of bodies within these structures are described. The structures often display a layered character, with each layer corresponding to triple systems in which a particular body departs during the decay. These layers alternate with zones in which the decay does not occur on such short time scales, and the bodies are flung outward without this leading to a departure, or undergo simple interactions. In the zones of rapid decay, the departure of one of the bodies occurs after one or a few triple encounters between the components.  相似文献   

Search for periodic orbits in the general three-body problem     

P. P. Iasko  V. V. Orlov 《Astronomy Reports》2014,58(11):869-879

An original method for searching for regions of initial conditions giving rise to close to periodic orbits is proposed in the framework of the general three-body problem with equal masses and zero angular momentum. Until recently, three stable periodic orbits were known: the Schubart orbit for the rectilinear problem, the Broucke orbit for the isosceles problem, and the Moore eight-figure orbit. Recent studies have also found new periodic orbits for this problem. The proposed method minimizes a functional that calculates the sum of squared differences between the initial and current coordinates and the velocities of the bodies. The search is applied to short-period orbits with periodsT < 10τ, where τ is the mean crossing time for the components of the triple system. Twenty one regions of initial conditions, each corresponding to a particular periodic orbit, have been found in the current study. A criterion for the reliability of the results is that the initial conditions for the previously known stable periodic orbits are located inside the regions found. The trajectories of the bodies with the corresponding initial conditions are presented. The dynamics and geometry of the orbits constructed are described.  相似文献   

Optimization of the transfer trajectory of a low-thrust spacecraft for research of Jupiter using an Earth gravity-assist maneuver   总被引：1，自引：0，他引：1  

M. S. Konstantinov  A. A. Orlov 《Solar System Research》2014,48(7):606-612

The paper analyzes the possibility of the use of a gravity-assist maneuver for flight to Jupiter. The advantage of the Earth gravity-assist maneuver in comparison with the direct transfer in terms of reduction of amount of energy required per transfer is considered. Quantitative and qualitative evaluations of two transfer profiles are given.  相似文献   

Dynamic status of the wide multiple system α Centauri + Proxima     

A. S. Matvienko  V. V. Orlov 《Astrophysical Bulletin》2014,69(2):205-210

We study the dynamics of a wide multiple system α Centauri + Proxima. The total energy of the system was estimated according to the available observational data on masses, coordinates, proper motions, and radial velocities of its components. To account for the effect of the observational data errors on the result, we have implemented the Monte Carlo method. From N = 10⁶ statistical tests we show that with the probability of about 90% the motion is hyperbolic, i.e., α Cen AB and Proxima will after a while diverge from each other by a considerable distance. We also perform numerical modeling of dynamic evolution of the wide pair α Cen AB + Proxima in the regular field of the Galaxy. The trajectory of relative motion is constructed. The components diverge from each other by a distance of 20 pc over the time scale of about 200 Myr. The critical parameter for determining the dynamic status of the system is the radial velocity of the C component (Proxima), known with an error of 200 ms^?1. For a reliable determination of the nature of motions in the system, we have to decrease the radial velocity error by at least an order of magnitude.  相似文献   

Apsidal Motion in Detached Binary Stars: Comparison of Theory and Observations     

A. V. Petrova  V. V. Orlov 《Astrophysics》2002,45(3):334-341

A list of 62 detached binaries having reliable data on the rotation of the line of apsides is considered. Theoretical estimates of the rate of apsidal motion are obtained. These estimates are compared with observational data. It is shown that cases in which the theoretical estimate exceeds the observed value are several times more frequent than cases in which the theoretical value is lower than the observed one. This discrepancy increases when systems with more reliable observational data are considered.  相似文献   

Approach-ejection correlation in the general three-body problem     

V. V. Orlov  A. V. Petrova  A. I. Martynova 《Astronomy Letters》2001,27(7):470-474

The relations between parameters of triple approaches and the lengths of subsequent ejections are analyzed for the general three-body problem with components of equal masses and zero initial velocities. A statistically significant correlation is shown to exist between the closeness of approaches and the lengths of subsequent ejections: closer approaches generally result in longer ejections. We have found several systems that evolve to a temporary quasi-stable chain-like configuration.  相似文献