Cosmic Research

The Meteor-M № 1 and Meteor-M № 2 satellites had a group of omnidirectional counters and a group of narrow-beam multi-channel telescopic instruments. The telescopes were mounted along the velocity vector of the satellite and radially to the zenith. During flights through the inner belt in the direction from the equator to the south pole, the latitudinal profiles of protons in the channels of omnidirectional counters and in the channels of telescopes of different directions were located one below the other. When flying in the opposite direction, the “omnidirectional” profile approximately maintained its position, and the profiles in the channels of the telescopes of different directions shifted relative to the “omnidirectional” profile in opposite directions. The high-altitude course of the protons of the inner belt in the channels of the telescopes is a complex of elements of various shapes. The relative position of these elements depends on the direction of the telescope’s axis and the direction of the satellite’s motion. Algorithms and calculation results for the orientation of the axes of the telescopes relative to the magnetic field vector are presented. It is shown that the orientation of the axes of the telescopes depends on the longitude and on the direction of motion of the satellite. Depending on this, different areas of the pitch-angular distribution of particles fall into the field of view of the telescope. Based on a simple model of the pitch angular distribution of proton fluxes in the form of j≈sin(α)^′, the fluxes that can enter the field of view of the telescope were calculated. It was taken into account that part of the intake cone itself may lie inside the cone of atmospheric losses. The simulation results of latitude and altitude movements showed a qualitative agreement with the satellite observations.

The paper presents the results of the reduction of the full three-dimensional (in spatial coordinates) transport equation of galactic cosmic rays in longitude. It is shown that in the simplest case of the quasi-stationary equation, usually used to describe the intensity of galactic cosmic rays near solar activity minima, when only the coefficient describing the particle drift depends on longitude, the resulting axisymmetric equation does not reduce to an a priori 2D-equation, in which the longitudinal component of the particle drift velocity is dropped from consideration. The presence of the drift modulation mechanism leads to the fact that in the 2D reduced equation the total drift velocity acquires a factor −1 ≤ F ≤ 1, depending on the latitude, and an additional term appears in the equation, taking into account the contribution of the three-dimensionality of the original equation.

Based on the results of measurements near the equatorial plane of fluxes and spectra of H⁺ and O⁺ ions of the magnetospheric ring current (RC) on the Explorer-45, AMPTE/CCE, CRRES and Van Allen Probes satellites, a systematic analysis of the spatial distributions of the energy density of these ions on the recovery phase of magnetic storms was carried out. Nine storms of varying intensity were considered, with max|Dst| from 59 to 307 nT. The radial profile of the ion energy density of the RC is characterized by the position of its maximum (L_m) and by the ratio of the ion energy density and the magnetic field at this maximum (β_m), and at L > L_m this profile is approximated by the dependence w(L) = w₀ exp(−L/L₀). The distributions of the parameter L_m depending on the index Dst and on MLT, as well as the parameters β_m, w₀ and L₀ depending on Dst, MLT and L_m were obtained. For H⁺ and O⁺ ions, as well as for low-energy (E < 60 keV) and higher-energy ions, these distributions are different, which is associated with different loss rates of these ions. It is shown that for the RC protons, the average values of the parameters L_m and β_m usually increase as the recovery phase develops, and the dependence L_m(Dst) is significantly stronger than in the main phase of storms. During strong storms, on the fast recovery phase, the average value of the L₀ parameter for H⁺ ions with E ≈ 1−300 keV decreases from ~1.7 to ~1.4 (dominance of the RC symmetrization effect by MLT), and for O⁺ ions of the same energies, L₀ increases from ~0.9 to ~1.2 (dominance of the RC ion losses). According to the estimates made, on the slow recovery phase of strong storms, a significant contribution, from 30 to 50 %, to the total energy of the ion RC can be related to the region on 7 ≤ L ≤ 10. It is shown that for some storms the contribution of the RC ions at L ≤ 10 to the Dst value is well described by the Dessler–Parker–Sckopke relation, but in other measurements considered here, especially during very strong storms, the contribution of the RC to the Dst value is no more than 40–60 %, and the rest is the part of other magnetospheric current systems.

In the ionosphere of Mars, dust can remain at high altitudes as a result of combustion of meteoric bodies and its subsequent condensation. These dust particles acquire charges under the influence of solar radiation, interaction with charged particles of the ionosphere and solar wind, and also as a result of the triboeffect. In such plasma-dust systems, various wave oscillations can occur. In particular, taking into account the inhomogeneities of the plasma concentration of Martian plasma-dust clouds and the presence of a magnetic field of Mars, although weak, but significant for these processes, it is possible to excite lower hybrid drift waves. The conditions under which the propagation of lower hybrid drift waves in the dusty plasma of the ionosphere of Mars and the development of modulation instability of these waves are possible are considered. A possible connection is shown between the occurrence of low-frequency noise on Mars and the development of lower hybrid drift turbulence in plasma-dust systems of Mars, in which sufficiently large electric fields are observed. The influence of the magnetic field on the excitation of lower hybrid drift waves is shown and it is calculated for which regions of the magnetic field in the dust clouds of Mars lower hybrid drift waves of certain frequency ranges can be excited.

The paper considers the problem of identifying pairs of tracks of near-Earth space objects that are absent from orbital databases and independently observed by one or several optical telescopes in one or many observation sessions. An algorithm for preliminary rejection of pairs of tracks — candidates for identification based on estimates of motion invariants is proposed. An exact solution to the problem of identifying two tracks is obtained using the generalized likelihood ratio method. A new algorithm for estimating orbital parameters (in the absence of a priori orbital data) is proposed for one or two optical tracks, between which there may be a long time gap.