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821.
I. V. Mingalev V. S. Mingalev O. V. Mingalev B. Kazeminejad H. Lammer H. K. Birnat H. I. M. Lihteneger K. Schvingenschu H. O. Ruker 《Cosmic Research》2009,47(2):114-125
The results of numerical simulation of the general circulation in the Titan’s atmosphere at heights from 0 to 250 km are presented, obtained using a new model based on numerical solution of complete equations of motion of viscous compressible gas at the temperature distribution given by an empirical model. The model uses no hydrostatic equation and, as compared with traditional models, has higher resolution in vertical and over horizon. The results presented differ from results of other models and agree with the vertical profile of the zonal component of wind velocity measured by the Huygens spacecraft. Interpretation of this profile is given, including its main peculiarity consisting in a nonmonotonic behavior at heights from 60 to 75 km. 相似文献
822.
On the basis of generalization of the results of extensive trajectory calculations for trial charged particles moving in the geomagnetic field the method of calculation of effective vertical cutoff rigidity, taking into account the values of K p -index and local time, is developed. The IGRF and Tsyganenko-89 models are used for the geomagnetic field. A comparison of the results of model simulations with the experimental data on penetration of charged particles into near-Earth space is made, and penetration functions for typical spacecraft orbits are calculated. 相似文献
823.
B. I. Rabinovich 《Cosmic Research》2009,47(4):287-298
A mathematical model of the non-steady-state magnetosphere of the ocean of Jupiter’s moon Europa is described. This magnetosphere is induced by the magnetic field of Jupiter, and its interaction with the Europa ocean is considered. Rotation of the ocean and its icy crust with respect to the hard core is described by a system of integro-differential equations with singular kernels, the values of the Reynolds number and magnetic Reynolds number being large for the system. The solution to these equations obtained by the methods of operational calculus is analyzed quantitatively and compared with a model experiment. 相似文献
824.
O. M. Belotserkovskii I. V. Mingalev V. S. Mingalev O. V. Mingalev A. M. Oparin V. M. Chechetkin 《Cosmic Research》2009,47(6):466-479
The paper is devoted to studying the mechanisms of formation of cyclones in the Earth’s atmosphere with the help of numerical
modeling using the complete system of gas-dynamic equations. The results of modeling have shown that cyclones can appear in
horizontal stratified shear flows of warm and wet air masses with horizontal direction of gradients of the wind velocity components
as a result of small disturbances of pressure which can be produced by Rossby waves. 相似文献
825.
The results of reconstruction of uncontrolled attitude motion of the Foton M-2 satellite using measurements with the accelerometer TAS-3 are presented. The attitude motion of this satellite has been previously
determined by the measurement data of the Earth’s magnetic field and the angular velocity. The TAS-3 data for this purpose
are used for the first time. These data contain a well-pronounced additional component which made impossible their direct
employment for the reconstruction of the attitude motion and whose origin was unknown several years ago. Later it has become
known that the additional component is caused by the influence of the Earth’s magnetic field. The disclosure of this fact
allowed us to take into account a necessary correction in processing of TAS-3 data and to use them for the reconstruction
of the attitude motion of Foton M-2. Here, a modified method of processing TAS-3 data is described, as well as results of its testing and employing. The testing
consisted in the direct comparison of the motion reconstructed by the new method with the motion constructed by the magnetic
measurements. The new method allowed us to find the actual motion of Foton M-2 in the period June 9, 2005–June 14, 2005, when no magnetic measurements were carried out. 相似文献
826.
We study the influence of additive and parametric slowly varying harmonic (at the Chandler frequency and doubled frequency) and stochastic Gaussian broadband perturbations on mathematical expectations, variances, and covariations of oscillations of the Earth’s pole. The influence of perturbations on both regular and irregular stochastic oscillations is considered in detail. Results of numerical experiments are presented. The developed models and software are included into information resources on the fundamental problem “Statistical dynamics of the Earth’s rotation” of Russian Academy of Sciences. 相似文献
827.
828.
William F. Dempster M. Nelson S. Silverstone J.P. Allen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
A mixed crop consisting of cowpeas, pinto beans and Apogee ultra-dwarf wheat was grown in the Laboratory Biosphere, a 40 m3 closed life system equipped with 12,000 W of high pressure sodium lamps over planting beds with 5.37 m2 of soil. Similar to earlier reported experiments, the concentration of carbon dioxide initially increased to 7860 ppm at 10 days after planting due to soil respiration plus CO2 contributed from researchers breathing while in the chamber for brief periods before plant growth became substantial. Carbon dioxide concentrations then fell rapidly as plant growth increased up to 29 days after planting and subsequently was maintained mostly in the range of about 200–3000 ppm (with a few excursions) by CO2 injections to feed plant growth. Numerous analyses of rate of change of CO2 concentration at many different concentrations and at many different days after planting reveal a strong dependence of fixation rates on CO2 concentration. In the middle period of growth (days 31–61), fixation rates doubled for CO2 at 450 ppm compared to 270 ppm, doubled again at 1000 ppm and increased a further 50% at 2000 ppm. High productivity from these crops and the increase of fixation rates with elevated CO2 concentration supports the concept that enhanced CO2 can be a useful strategy for remote life support systems. The data suggests avenues of investigation to understand the response of plant communities to increasing CO2 concentrations in the Earth’s atmosphere. Carbon balance accounting and evapotranspiration rates are included. 相似文献
829.
Corey S. Jamieson Agnes H.H. Chang Ralf I. Kaiser 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Mixtures of molecular nitrogen and methane have been identified in numerous outer Solar Systemices including the icy surfaces of Pluto and Triton. We have simulated the interaction of ionizing radiation in the Solar System by carrying out a radiolysis experiment on a methane – molecular nitrogen ice mixture with energetic electrons. We have identified the hydrogen cyanide molecule as the most prominent carbon–nitrogen-bearing reaction product formed. Upon warming the irradiated sample, we followed for the first time the kinetics and temporal evolution of the underlying acid–base chemistry which resulted in the formation of the cyanide ion from hydrogen cyanide. On the surfaces of Triton and Pluto and on comets in Oort’s cloud this sort of complex chemistry is likely to occur. In particular, hydrogen cyanide can be produced in low temperature environments (Oort cloud comets) and may be converted into cyanide ions once the comets reach the warmer regions of the Solar System. 相似文献
830.
T. Sindelarova D. BuresovaJ. Chum F. Hruska 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Ionospheric effects of meteorological origin observed by the continuous HF Doppler sounder over the Czech Republic are reported in this paper. We focused on detection of waves of periods 1–10 min. We discuss the influence of dynamics and intensity of active weather systems on the occurrence of short period waves and dependence of the observed ionospheric effects on the height of reflection of the sounding radio wave. We observed 3–5 min waves during a severe weather event in summer and 2.5–4 min waves during a severe weather event in winter. We excluded possible geomagnetic origin of these oscillations by the analysis of fluctuations of the local geomagnetic field. In eight cases of 10, wave activity in the analysed period range was not significantly increased comparing to quiet days. The intensity of weather systems as well as the location of potential sources of waves towards the points of HF Doppler shift observation influence significantly the occurrence of infrasonic waves in the ionosphere. The results in Central Europe differ considerably from those previously obtained in North America. As a possible reason, we discuss different intensity and dynamics of weather systems in both regions. 相似文献