A Study of the Luminescence of the Lyman–Birge–Hopfield Bands in the Atmospheres of the Earth and Titan

Cosmic Research - Calculations were made of the volume and integral emission intensities of the Lyman–Birge–Hopfield (LBH) bands of molecular nitrogen at 146.4, 138.4, 135.4, and 132.5...     

Illumination of the Earth’s ionosphere by the vacuum ultraviolet radiation reflected by the moon

The spectral curve of the flux density of the radiation, which is reflected by the full moon towards the Earth’s ionosphere within a wavelength range of 200–1700 Å, has been presented. This curve is obtained by the approximation of space experiment data available in the scientific literature on the lunar spectral albedo and solar spectrum. Estimates of maximum values of spectral densities of fluxes reflected by the full moon in the neighborhood of wavelengths of ionization of basic ionospheric particles (neutral atoms of H I, He I, N I, O I, and Ar I and ions of He II, N II, O II, Ar II, N III, O III, and Ar III, as well as molecules of H₂, N₂, and O₂) are given.     

High-speed streams of the solar wind near the earths’s orbit and their sources on the sun according to stereoscopic observations in the minimum of the 23rd cycle

Based on the results of plasma and magnetic measurements at three different points of the heliosphere and telescopic observations of the Sun from these points we study simultaneously high-speed streams (HSS) of the solar wind (SW) near the Earths’s orbit and coronal holes (CH) that have generated them. The data from spacecraft STEREO-A, STEREO-B, ACE, and SOHO are used together with ground-based observations from March 2007 to May 2008. In this period there existed HSS whose sources represented CH of various polarity, geometry, and location relative to the heliographic and heliomagnetic equators. Dependence of SW parameters on mutual positions of spacecraft with respect to CH and heliospheric current sheet, and also on heliolatitude and geometry of the CH is revealed. A difference of more than 5° in locations of spacecraft with respect to the heliospheric current sheet in November 2007 allowed us to discover a heliolatitude velocity gradient of the SW streams between the STEREO-A and STEREO-B spacecraft. On the average this gradient at that time was equal to 20 km/s per degree. Substantial variations in SW streams associated with variations of the HSS SW sources during a few hours or days were also observed. This variability makes it difficult to use the data of spacecraft STEREO-B for sufficiently accurate prediction of SW properties in the near-Earth space by the method of simple advanced ti me shift due to heliolongitude difference between a spacecraft and the Earth even in solar activity minimum.     

Stochastic models of the earth’s rotation taking the effects of the moon and planets into account

A generalization of kinetic and spectral and correlation equations of fluctuations in the Earths rotation is made taking into account the effect of the Moon and planets (these equations form the basis for corresponding stochastic models). Special attention is paid to a parameterized version of kinetic equations based on the method of normal approximation. The application of linear stochastic models for obtaining the spectral and correlation characteristics of the Earths rotation is considered, including the case of random parameters of the tensor of inertia of a deformable Earth. The results can be used for constructing stochastic models of the Earths rotation over time intervals of 6–10 years.Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 1, 2005, pp. 54–66.Original Russian Text Copyright © 2005 by Markov, Dasaev, Perepelkin, I. N. Sinitsyn, V. I. Sinitsyn.     

Features of the Motion of the Earth’s Geographic North Pole and Jumping in the Geomagnetic Field

Cosmic Research - The results of an analysis and comparison of times of appearance of the features of the long-term displacement of the geographic North Pole over the Earth’s surface and the...     

Analysis of the orbital motion of the asteroid Apophis’ satellite

We have analyzed the orbital disturbed spacecraft motion near an asteroid. The equations of the asteroidocentric spacecraft motion have been used with regard to three perturbations from celestial bodies, the asteroid’s nonsphericity, and solar radiation pressure. It has been shown that the orbital parameters of the main spacecraft and a small satellite with a radio beacon can be selected such that the orbits are rather stable for a fairly long period of time, i.e., a few weeks for the main spacecraft with an orbit initial radius of ~0.5 km and a few years before approaching Apophis with the Earth in 2029, for a small satellite at an orbit initial radius of ~1.5 km. The initial orientation of the spacecraft orbital plane perpendicular to the sunward direction is optimal from the point of view of the stability of the spacecraft flight near an asteroid.     

A Study of the Reflection of Radio Waves from the Plasma Region on the Track behind an Axisymmetric Body Moving in the Earth’s Atmosphere

The results of numerical calculation of the dependences of the electron density, the eigenfrequency and the dielectric plasma permeability on the geometric parameters and the altitude of body motion in the near and far wake behind a thin conical body with a spherical nose blunting have been presented. The electron density maximum has been shown to be located in the region of the neck of the near wake behind the body, which determines the type of this region (supercritical or subcritical). This in turn affects the propagation of radio waves through this plasma region. A comparative analysis was performed for two different bodies with the same ballistic coefficient values. No characteristic distinctions were revealed in the values of electron density or the plasma eigenfrequency in the near and far wake behind these bodies. However, it has been shown that there are differences in the values of the distance from the bottom cross section to the neck of the near wake behind these bodies.     

Speeding up the Development of Space Industry to Meet the New Challenge

This paper discusses the urgency to further develop China's space technological industry;analyzes the gaps between China and other advanced countries in space industry,including technological level,development scale,application scope and investment;describes the current severe situation that the China's space industry is faced with and proposes the overall objective,guiding principles and major tasks of China's space technological sector in the Ninth-Five Year Plan and the coming decade.Finally,it proposes some policies and effective measures to speed up the development of China's space industry to meet the challenge in the 21st century.     

The Achievements and the Future of the Development of China's Space Technology

China's space cause is based on the development of missile technology. In the 1950s, new China, which was just founded, decided to keep pace with the jet technology times, to begin developing missile and rocket science and technology, and to establish China's new space scientific and technological industry.     

Relationship between the fluxes of relativistic electrons at geosynchronous orbit and the level of ULF activity on the Earth’s surface and in the solar wind during the 23rd solar activity cycle

We present the results of a cross-correlation analysis made on the basis of Spearman’s rank correlation method. The quantities to correlate are daily values of the fluence of energetic electrons at a geosynchronous orbit, intensities of ground and interplanetary ultra-low-frequency (ULF) oscillations in the Pc5 range, and parameters of the solar wind. The period under analysis is the 23rd cycle of solar activity, 1996–2006. Daily (from 6 h to 18 h of LT) magnetic data at two diametrically opposite observatories of the Intermagnet network are taken as ground-based measurements. The fluxes of electrons with energies higher than 2 MeV were measured by the geosynchronous GOES satellites. The data of magnetometers and plasma instruments installed on ACE and WIND spacecraft were used for analysis of the solar wind parameters and of the oscillations of the interplanetary magnetic field (IMF). Some results elucidating the role played by interplanetary ULF waves in the processes of generation of magneospheric oscillations and acceleration of energetic electrons are obtained. Among them are (i) high and stable correlation of ground ULF oscillations with waves in the solar wind; (ii) closer link of mean daily amplitudes of both interplanetary and ground oscillations with ‘tomorrow’ values of the solar wind velocity than with current values; and (iii) correlation of the intensity of ULF waves in the solar wind, normalized to the IMF magnitude, with fluxes of relativistic electrons in the magnetosphere.     

Proton precipitation to the equator of the isotropic boundary during the geomagnetic storm on November 20–29, 2003

Using NOAA satellite data, we consider the peculiarities of precipitation dynamics for energetic protons to the equator of the isotropy boundary during a geomagnetic storm. In addition to two well-known types of proton precipitation events, a new third type of precipitation is distinguished, which is observed on the dayside at relatively high latitudes. The assumption is made that the third-type precipitation in the dayside sector is associated with the development of ion-cyclotron instability. Apparently, the transverse anisotropy of energetic protons, which is necessary for the development of instability, is caused by splitting of drift shells. All three types of precipitation have different generation regions and different time dynamics during storms. The maximum precipitation intensity takes place in the evening sector during the main phase of a storm. At the storm’s recovery phase major losses of protons of the ring current are due to precipitation in the day and morning sectors.     

INTERBALL-1 Observations of the Kilometric “Continuum” of the Earth's Magnetosphere

The electromagnetic radio-frequency emission of the inner region of the Earth's plasmasphere discovered recently by the GEOTAIL satellite [4] and referred to as the kilometric continuum was observed by the INTERBALL-1 satellite (1995–2000) in the 100–500 kHz band in the AKR-X experiment. During a period of low solar activity (1995–1997), this continuum was found leaving the inner plasmasphere at geocentric distances of 2–4R _E as isolated pencil-like (1°–6°) beams located in the magnetic equator plane. During a time of high solar activity (1999–2000), the occurrence of the emission was extremely rare (it was observed only at a considerable fall of this activity). If detected, at the same geocentric distances (2–4R _E) the continuum demonstrated a strongly variable and perturbed character, as well as a considerably larger extension of the beam over the geomagnetic latitude (10°–20° and more). In addition, quasi-periodic (QP) signals, similar to the observed QP emissions of Jupiter, were sometimes detected in this period. The probable nature of the observed features of the kilometric continuum is briefly discussed.     

Dynamics of the Radiation Environment in the Near-Earth Space in September–November 2020 according to the Meteor-M and Electro-L Satellite Data

Cosmic Research - The results of a comparative analysis from Russian satellite data on the radiation environment in the near-Earth space during September–November 2020 are presented. The...     

Variations in the Parameters of Radio Waves in the Earth’s High-Latitude Ionosphere on the Satellite–Satellite Paths during the Geomagnetic Storm of June 22–23, 2015

Cosmic Research - This paper analyzes the results of about 100 radio occultation sessions of sounding of the high-latitude (>65 °N) lower ionosphere of the Earth’s Northern...     

Elimination of the Potential Hazard of the Long March 4 Launch Vehicle's In-orbit Breakup

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On Saturn’s rotation relative to a center of mass under the action of the gravitational moments of the Sun and Jupiter

Saturn’s rotation relative to a center of mass is considered within an elliptic restricted three-body problem. It is assumed that Saturn is a solid under the action of gravity of the Sun and Jupiter. The motions of Saturn and Jupiter are considered elliptic with small eccentricities e_S and e_J, respectively; the mean motion of Jupiter n_J is also small. We obtain the averaged Hamiltonian function for a small parameter of ε = n_J and integrals of evolution equations. The main effects of the influence of Jupiter on Saturn’s rotation are described: (α) the evolution of the constant parameters of regular precession for the angular momentum vector I₂; (β) the occurrence of new libration zones of oscillations I₂ near the plane of the celestial equator parallel to the plane of the Jupiter’s orbit; (γ) the occurrence of additional unstable equilibria of vector I₂ at the points of the north and south poles of the celestial sphere and, as a result, the existence of homoclinic trajectories; and (δ) the existence of periodic trajectories with arbitrarily large periods near the homoclinic trajectory. It is shown that the effects of (β), (γ), and (δ) are caused by the eccentricity e of the Jupiter’s orbit and are practically independent of Jupiter’s mass (within satellite approximation).     

Observations of the Subauroral Nonthermal Radio Emission of the Earth in 1995–1998

Results of almost four years of continuous observations of the subauroral nonthermal radio emission (SANE) onboard the Interball-1 satellite are presented. The main features of SANE are described and discussed: the intensity and character of a signal, its appearance in time, beam directivity, propagation distance, and other observed parameters.