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Vol 63, No 6 (2025)
Articles
ON THE PECULIARITIES OF THE REGISTRATION OF PROTONS OF THE INNER BELT ON METEOR SATELLITES BY OMNIDIRECTIONAL AND NARROWLY FOCUSED DETECTORS
Abstract
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.
Cosmic Research. 2025;63(6):579–589
579–589
ASSESSMENT OF THE EFFECTS OF SPACE WEATHER ON THE RELIABILITY OF THE READINGS OF MAGNETIC INCLINOMETERS
Abstract
The efficiency of subsurface resource development in the Arctic Zone of the Russian Federation (AZ RF) is closely linked to the need to minimize technogenic risks, particularly those arising from the influence of space weather on navigation systems operating at high latitudes within the auroral oval. Previous studies have described the mechanisms and extent of space weather effects on the increased measurement errors of magnetic inclinometers used in well geophysical surveys. Drawing on data from a reference magnetic station and an assessment of inclinometric measurement quality (i.e., the ratio of low-quality data to the total number of inclinometric surveys) for 2022–2024 from operating wells in the Russian Federation, this study provides a qualitative evaluation of the relative likelihood of disruptions to technological procedures caused by extreme additional errors of measuring instruments. To reduce technogenic risks during oil and gas well development in the AZ RF and on the continental shelf, a decision-support framework is proposed that integrates real-time geomagnetic conditions into geophysical survey processes. Statistical relationships are examined, observed deviations are assessed, and an approach to their interpretation is outlined.
Cosmic Research. 2025;63(6):590-600
590-600
3D AND 2D TRANSPORT EQUATIONS OF GALACTIC COSMIC RAYS IN MODERN HELIOSPHERE MODELS – I
Abstract
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.
Cosmic Research. 2025;63(6):601–609
601–609
SPACE WEATHER PHENOMENA OBSERVED IN EXPERIMENTS ON CUBESATS OF THE MSU CONSTELLATION-270 DURING THE 2024 HELIOGEOPHYSICAL DISTURBANCES
Abstract
The deployment of the MSU nanosatellite constellation “Sozvezdie-270” continues. To date, 20 CubeSat satellites have been launched with equipment for monitoring cosmic radiation and electromagnetic transients of various natures, including atmospheric, astrophysical and solar origin. This paper uses data from five CubeSats launched on June 27, 2023 (Avion, Monitor-2, Monitor-3, Monitor-4, UTMN-2) and two CubeSats launched on November 5, 2024 (Altair. ArcticSat). Each of them is equipped with DeCoR scintillation detectors for recording hard X-ray and gamma radiation and charged particles, specially developed at the SINP MSU for such experiments. The paper presents the results of observations of space weather phenomena that lead to significant changes in radiation conditions in near-Earth space. Such phenomena that can be recorded in experiments on the CubeSats of the “Sozvezdie-270” group include hard X-ray and gamma radiation from solar flares; solar cosmic rays (SCR) recorded on CubeSats in the polar cap region; variations in the intensity and spatial structure of the distribution of high-energy electron fluxes in the Earth’s outer radiation belt during magnetic storms caused by changes in solar wind parameters due to active processes on the Sun – both the arrival of coronal mass ejections in the Earth’s orbit and high-speed solar wind flows from coronal holes. The table of solar flares observed in HXR on the MSU CubeSats from September 2023 to February 2025 is given.
Cosmic Research. 2025;63(6):610–623
610–623
ION RING CURRENT ON THE RECOVERY PHASE OF MAGNETIC STORMS
Abstract
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 (Lm) and by the ratio of the ion energy density and the magnetic field at this maximum (βm), and at L > Lm this profile is approximated by the dependence w(L) = w0 exp(−L/L0). The distributions of the parameter Lm depending on the index Dst and on MLT, as well as the parameters βm, w0 and L0 depending on Dst, MLT and Lm 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 Lm and βm usually increase as the recovery phase develops, and the dependence Lm(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.
Cosmic Research. 2025;63(6):624–643
624–643
A METHOD FOR NUMERICAL CALCULATION OF THE PARTICLE SPATIAL DISTRIBUTION DURING NON-STATIONARY DIFFUSION IN AN INFINITE REGION
Abstract
Solar cosmic rays are generated in the solar atmosphere, while their registration is carried out in interplanetary space in most events in the Earth’s orbit. To establish a relationship between the registered intensity of solar cosmic rays and the intensity at the source, it is necessary to take into account its change during injection and propagation in interplanetary space. During diffusion propagation of particles in the case of a non-stationary source, a strong change in the spatial distribution of particles occurs, which complicates the application of numerical solution methods. Here, we offer a solution method based on using a quasi-self-similar variable. The method allows obtaining a quasi-self-similar variable and a missing boundary condition, guaranteeing the conservation of the total number of diffusing particles. Comparison of the obtained numerical solution with the known exact solution for a point source impulsed in time shows sufficient accuracy except for a small vicinity of the source. We have solved the case with a non-stationary point source. The balance between the total numbers of injected and diffusing particles, depending on the time, shows sufficient accuracy for the solution. The obtained numerical solutions confirm the method’s applicability for calculating the non-stationary equation of particle transport in an infinite space.
Cosmic Research. 2025;63(6):644–649
644–649
LOWER HYBRID DRIFT WAVES IN THE DUSTY IONOSPHERE OF MARS
Abstract
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.
Cosmic Research. 2025;63(6):650-662
650-662
FEATURES OF SOLAR ACTIVITY MANIFESTATIONS IN COSMIC RAYS MAY 10–11, 2024
Abstract
The paper presents the results of an analysis of solar and geomagnetic activity, variations in cosmic ray fluxes during the period of May 10–11, 2024. At that time, the largest geomagnetic storm in the last 20 years occurred, caused by the arrival of several solar coronal plasma emissions to the Earth, which initiated the Forbush decrease in galactic cosmic rays (GCL) on May 10–11, 2024. This event was registered by the global network of ground-based neutron monitors (NM). The peculiarity of this period lies in the fact that, along with a significant decrease in GCL fluxes in the main phase of the geomagnetic storm, the GOES and SOHO spacecraft recorded the arrival of a stream of high-energy solar cosmic rays into near-Earth space. The source of these particles was a powerful solar flare of magnitude X5.8/2B (coordinates S17W44), which began on May 11 at 01:10 UT. SCL fluxes in a wide range of energies began to be observed on spacecraft almost simultaneously, and at ~02:10 UT, a short-term increase in cosmic rays began, recorded by high-latitude terrestrial NM, marked as the GLE 74 event. Thus, the ground-based installations demonstrated a complex behavior of particle fluxes due to the superposition of SCL fluxes on modulated HCL fluxes during Forbush lowering. The main focus of the work is on the assessment of the possible contribution of SCL fluxes to the observed increases in the NM count. The analysis uses data from the ground-based NM network, as well as data from CL measurements by CARPET instruments and neutron detectors located at the Dolgoprudnenskaya Scientific Station of the FIAN, at the Eurasian National University (Astana, Republic of Kazakhstan) and at the CASLEO Astronomical Complex (Argentine Andes). To determine the energy spectra of the SCL, measurement data from the GOES and SOHO spacecraft are used. Cosmic ray flux measurements are analyzed in conjunction with data on solar, interplanetary, and geomagnetic activity.
Cosmic Research. 2025;63(6):663-673
663-673
TRACK IDENTIFICATION AND ESTIMATION OF ORBITS PARAMETERS OF MAN-MADE SPACE OBJECTS FIRST DETECTED BY TELESCOPES
Abstract
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.
Cosmic Research. 2025;63(6):674–686
674–686