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581.
Altitude—temporal cross-sections q(z, t) of atmospheric ionization rates by solar protons above the polar regions were calculated using the GOES-10 satellite data on solar proton fluxes for the period of solar proton flare (SPF) on July 14, 2000. The values of q(z, t) were used further in calculations of variations of the atmospheric chemical composition during the flare in the northern
and southern polar regions (70°N and 70°S) by two different 1D photochemical models of the atmosphere (neutral and charged
components). The calculation results have shown considerable variation of the ozone content after SPF: a decrease of [O3]
was about 80% at altitudes of 65–75 km above northern and 25% in the layer of 55–65 km above the southern polar region. Such
decrease of the ozone content is a result of reactions with [NO] and [OH] whose concentrations have grown substantially during
SPF. According to calculations, the increase of electron concentration during SPF has reached 3–4 orders of magnitude at altitudes
of 50–80 km. A comparison of the calculation results with the observational data on [NO], [NO2], and [O3] from the UARS and HALOE satellites for 70°N have shown a good qualitative correspondence, however, for variations of nitric oxides there are quantitative
discrepancies. 相似文献
582.
B. B. Kreisman 《Cosmic Research》2012,50(1):65-75
Within the framework of the circular restricted three-body problem a family of inverse periodic orbits around the two attracting
bodies (the Egorov’s family) and families generated by it at the 1:1, 2:1, and 3:1 resonances for three-dimensional orbits
in the Sun-Earth and Earth-Moon systems are considered. Their relationship with families generated by orbits around the libration
points L
1, L
2 and L
3 is investigated. One of the families contains periodic solutions that seem promising as possible orbits for the space radio
telescope of the Millimetron project. 相似文献
583.
Solar, geomagnetic and cosmic ray intensity changes, preceding the cyclone appearances around Mexico
J. Prez-Peraza S. Kavlakov V. Velasco A. Gallegos-Cruz E. Azpra-Romero O. Delgado-Delgado F. Villicaa-Cruz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1601-1613
Recently it has been suggested that there exist specific changes in the cosmic ray intensity and some solar and geomagnetic parameters during the days, preceding the hurricane appearances over the North Atlantic Ocean. To understand better these phenomena, data for all hurricanes born not only over the Atlantic but also over the Pacific waters in the last 55 years that hit the Mexican borders were elaborated. As basic hurricane parameters the maximum rotational velocity and the estimated total energy were used. To avoid any interference all hurricanes, overlapping the preceding ones with more than 20 days were not included. Then the behavior of the cosmic ray (CR) intensity, the sunspot (SS) numbers, and the geomagnetic parameters (AP) and (KP) in 35 days prior and 20 days after the cyclone start were investigated. The CR, SS, AP and KP showed much more intensive disturbances in the periods preceding and following the hurricane appearance. For SS this disturbance gradually increase with the hurricane strength. A characteristic peak in the CR intensity appears before the hurricane start. But its place varies between 5 and 20 days before that start. Specific changes were observed in the SS. For major hurricanes they begins sometimes more than 20 days in advance. The AP and the KP show series of bursts, spread over the whole period of 30 preceding days. The obtained results from the performed correlational analysis are enough interesting to motivate a further statistical analysis with more precise techniques: in particular a common periodicity of 30 years found in the number of tropical storms landing into Mexico, the averaged rotational wind velocity and the ACE must be studied in connection with the solar Hale cycle. Using coherence wavelet spectral analysis we present a comparative study between one terrestrial and one cosmophysical phenomena that presumable influence hurricanes development: African dust outbreaks versus cosmic rays for all North Atlantic tropical cyclones. It is shown that the cosmophysical influence cannot be considered as a negligible effect. 相似文献
584.
A system for recording and analysis of flight information including the technical condition of a control object and the state of its controller’s health in real time aboard a flight vehicle and in ground-based air traffic control centers is described. 相似文献
585.
A possibility to prevent collisions with the Earth of dangerous celestial bodies by directing at them small asteroids is considered.
It is proposed to solve this problem using a gravitational maneuver near the Earth. 相似文献
586.
The characteristics of a master time and master-time dissemination subsystem for a collision avoidance system acceptable to the Air Transport Association of America are investigated. Selection of a time scale, a ground-station timing standard, and a synchronization technique are discussed. The conclusions are that a uniform time scale is ideal for the application, that a minimum of four cesium-beam standards are needed at each ground station, and that portable-clock synchronization is the only synchronization technique feasible at the present time. Considerations that suggest use of a nonuniform time scale are noted, and means of minimizing the adverse effects of the offsets necessitated by such an approach are described. Both single-master and weighted-average implementations of the time scale are discussed. 相似文献
587.
Based on the data of numerical simulation of the test stand gas-liquid ejector operation, the fields of gasodynamic flow parameters in the gas flue channel are determined. The test stand operation in real time and processes of interaction between the flow of combustion products and neutralizing liquid are also analyzed. 相似文献
588.
The concept of “space patrol” is considered, aimed at discovering and cataloging the majority of celestial bodies that constitute
a menace for the Earth [1, 2]. The scheme of “optical barrier” formed by telescopes of the space patrol is analyzed, requirements
to the observation system are formulated, and some schemes of sighting the optical barrier region are suggested (for reliable
detection of the celestial bodies approaching the Earth and for determination of their orbits). A comparison is made of capabilities
of electro-jet engines and traditional chemical engines for arrangement of patrol spacecraft constellation in the Earth’s
orbit. 相似文献
589.
Translational-rotational motion of three planets modeled by viscoelastic balls in the gravitational field of mutual attraction
is studied in this paper. The system of equations of motion for the mechanical system under consideration is deduced from
the d’Alembert-Lagrange variational principle. Using the method of separation of motions, an approximate system of ordinary
differential equations, describing the translational-rotational motion of the planets, is obtained with taking into account
perturbations caused by elasticity and dissipation. The found steady-state motion of the system is an analog to triangular
libration points in the classical three-body problem. 相似文献
590.
N. A. Vlasova N. N. Pavlov M. I. Panasyuk N. N. Vedenkin T. A. Ivanova G. P. Lyubimov S. Ya. Reizman V. I. Tulupov 《Cosmic Research》2011,49(6):485-499
We compared fluxes of the 1–100 MeV solar energetic particles (SEP) measured in the interplanetary medium (ACE) and in the magnetosphere (Universitetsky-Tatiana, POES—in polar caps, and GOES-11—at geosynchronous orbit) during several SEP events of 2005–2006. Peak intensities of the SEP fluxes inside and outside the
magnetosphere were compared for each event. It is shown that observed inside-outside difference depends mainly on direction
of interplanetary magnetic field (IMF), on degree of the SEP anisotropy (pitch-angle distribution) in IMF, and on distance
of the dayside magnetopause from the Earth. 相似文献