RU2711554C1 - Method of formation of a group of artificial earth satellites for monitoring potentially dangerous threats in near-earth space in a mode close to real time - Google Patents

Abstract

FIELD: information technology.SUBSTANCE: group of inventions relates to AES information systems for detecting potential threats during monitoring of radiation environment, electromagnetic transitions: space and atmospheric bursts of gamma-, optical and UV-radiation. AES are equipped with spectrometric equipment and placed on orbits crossing L-shells of Earth radiation belts. For example, two circular orbits are used: low (500–650 km) solar-synchronous and medium (1,400–1,500 km) with an inclination of ~80°, as well as elliptic orbit with apogee of 8,000 km, perigee of 600–700 km and critical inclination of ~63.4°. For orbits there is a condition that the departure of the perigee argument is less than 3–4 °/year. Information can be transmitted to the Earth with a duty cycle of not less than 0.5–4 hours depending on the orbit, wherein the spectrometric equipment is synchronized with reference to a single world time.EFFECT: providing operational (in a mode close to "real time"), in a wide range of orbits of monitoring of the phenomena and objects which can represent various space threats.11 cl, 7 dwg

Description

Technical field

The invention relates to the field of monitoring in near-Earth space of natural and man-made phenomena and objects in near real-time mode with the aim of quickly identifying potentially dangerous threats, including radiation conditions, as well as electromagnetic transients - space and atmospheric gamma-ray bursts , bursts of optical and ultraviolet radiation from the Earth’s atmosphere.

State of the art

The natural and “man-made” space environment poses serious risks for space missions, both robotic and human. The risk is determined by the specifics of the planned missions - their duration, localization in outer space and orbital parameters. The specifics of natural conditions in outer space, including the variety of physical parameters of radiation fields creates, as a rule, real difficulties for modeling the situation and calculating risks. Real-time monitoring of space-based natural and man-made objects and phenomena - potential threats, is an optimal and effective way to reduce risks.

In the framework of the present invention, the following potentially dangerous factors in near-Earth outer space are attributed to the radiation environment: ionizing radiation; electromagnetic transients; anthropogenic sources of ionizing radiation in near-Earth space.

At the same time, ionizing radiation in the form of streams of charged particles (protons and electrons) of high energies of the Earth’s radiation belts, as well as energetic particles of solar cosmic rays, is one of the main damaging factors affecting the performance of space devices and the safety of manned flights. These flows experience very significant variations on a time scale from milliseconds to tens of years that cannot be described by existing quasistatic models of the Earth's radiation belts (see, for example, Mullen EG, Gussenhoven MS, Ray K., Violet MA A double-peaked inner radiation belt: cause and effect as seen on CRRES // IEEE Trans. Nucl. Sci. 1991. V. 38. P. 1713-1718; Myagkova I.N., Bogomolov A.V., Shugai Yu.S. Dynamics of relativistic flows of electrons in near-Earth space in 2001-2005 // Moscow University Herald. Series 3: Physics, Astronomy. 2010. No. 3. P. 77-80).

On the other hand, existing satellite measurements are carried out only for a limited number of orbits and a range of pitch angles (the angle between the particle velocity vector and the magnetic line of force) and cannot give a global picture of the spatio-temporal variations of radiation in near-Earth outer space (GC). Therefore, there is a need for radiation monitoring and operational forecasting of the Earth’s radiation environment in order to quickly assess the radiation conditions in the OKP to assess the radiation risks of space missions and generate alert signals for making decisions on their management; verification of modern calculation models of near-Earth space radiation fields.

Another potentially dangerous phenomenon is electromagnetic transients in the upper atmosphere, which are observed in different wavelength ranges - from the radio to the gamma range. Among these phenomena, TLE (Transient Luminous Events - light flashes mainly in the near ultraviolet and red ranges) and TGF (Terrestrial Gamma Flashes - gamma-ray bursts of terrestrial origin) are reliably experimentally identified. These phenomena can be associated with high-altitude electric discharges that occur when runaway electrons are exposed to avalanches of mesosphere, energetic electrons, and electromagnetic waves spewing from radiation belts occurring at heights of tens of kilometers in the upper atmosphere, and are global in nature [Surkov VV, Hayakawa M. Underlying mechanisms of transient luminous events: a review // Ann. Geophys. 2012. V. 30. No. 8. P. 1185-1212]. The energy released in them is large enough to have a significant effect on radio communications, modify the physical parameters of the mesosphere, and also have a direct effect on the onboard systems of stratospheric suborbital aircraft (see, for example, [Garipov G., Grigoriev A., Khrenov B ., Klimov P., Panasyuk M. High energy transient luminous atmospheric phenomena: the potential danger for suborbital flights // In "Extreme Events in Geospace", Ed. Buzulukova. Elsevier. 2017]).

Cosmic gamma-ray bursts of astrophysical origin can also be a potential hazard (see, for example, [Bhat PN, Meegan C.A., von Kienlin A. et al. The 3rd Fermi GBM gamma-ray burst catalog: the first six years // The Astrophysical Journal Supplement Series. V. 223. No. 2. P. 28]). Despite the great remoteness of the sources, they represent the most powerful processes in the universe such as a hypernova explosion, fusion of neutron stars, collapse of the magnetar magnetic field. The effect of quite rare, but very intense cosmic gamma-ray bursts on the Earth’s atmosphere has not yet been fully studied, but in terms of ionospheric disturbances it can be comparable to flares on the Sun.

Anthropogenic sources of ionizing radiation in near-Earth space - radionuclide energy sources, nuclear propulsion systems of spacecraft, pose a potential threat to other spacecraft located near the first. The detection and determination of the physical characteristics of "nuclear-active" spacecraft is an important element in reducing radiation risks [Anikeeva MA, Boyarchuk K.A., Ulin S.E. Detection of radioactive space debris from the spacecraft // Problems of Electromechanics. 2012.V. 126. No. 1. S. 13-18].

Among the main technical problems to be solved, the most mastered are satellite measurements of the fields of ionizing radiation. Of primary interest are streams of energetic particles: electrons with energies in excess of hundreds of keV and protons and nuclei with energies in excess of MeV units, capable of penetrating inside spacecraft (SC) and affecting the operation of their electronic equipment and crews. Such measurements began to be carried out from the beginning of the space era, and currently a number of spacecraft with onboard detectors of energetic charged particles are operating in near-Earth orbits. However, the task of operational monitoring of the spatial distribution of ionizing radiation in a significant region of near-Earth space has not yet been solved. Most satellite measurements of energetic particle fluxes are carried out in a limited range of space and pitch angles, and / or do not provide for prompt transmission and the required quality of ground processing of data.

Monitoring the fluxes of ionizing radiation in outer space is one of the most important technical tasks of applied cosmonautics. In addition to the fact that this task is extremely urgent from the point of view of studying the physical laws of the formation and spatiotemporal variations of such flows, such monitoring is highly necessary from the point of view of the occurrence of radiation hazard situations from the point of view of the trouble-free functioning of spacecraft. According to available expert estimates, more than half of failures and malfunctions in the spacecraft onboard systems are caused by an adverse effect on the spacecraft’s spacecraft materials and equipment, the main role being played by radiation. The main attention is paid to the flows of energetic charged particles in the near-Earth space, capable of penetrating into the spacecraft’s hull and affecting their electronic equipment. These are mainly flows of energetic electrons and protons of the Earth’s radiation belts; as well as short-term intense flows of energetic particles from powerful solar flares. It is believed that it is advisable to monitor the flows of charged particles in the following energy ranges: protons in the energy range from 1 to> 160 MeV and electrons in the energy range of 0.15-10 MeV.

It is known that real flows of charged particles in the vicinity of the Earth, even in geomagnetic-calm conditions, experience very significant medium and long-term variations associated with solar and geomagnetic activity, changes in the Earth’s magnetic field and the density of the upper atmosphere. And after powerful geomagnetic disturbances, even the appearance of new time zones of energetic electrons and protons is possible, which can then exist for up to several weeks or months.

In addition, significant flows of energetic particles injected during powerful solar flares can come into the Earth’s orbit. During such events, proton fluxes with energies of tens and hundreds of MeV, capable of penetrating behind the defense of the spacecraft, for up to several days can exceed the background fluxes of protons of galactic cosmic rays by 3-4 orders of magnitude or more. Such events are unpredictable.

For this reason, experimental measurements are needed that can provide information about the radiation situation in the orbits of the satellites in operation at the current time.

Measurements of fluxes of energetic charged particles are carried out by a number of spacecraft (SC). But practically all of these spacecraft measure the fluxes of energetic charged particles only in a limited region of space and in the range of pitch angles (the angle between the vectors of particle velocity and magnetic field induction B).

In particular, the system of geophysical observations of the American agency NOAA, which has been operating since the 1970s, is used, which uses the satellite of the POES series in low polar orbits and GOES in the geostationary orbit (simultaneously ≥2 satellite in each orbit). Also, in 2012, two NASA VanAllenProbes spacecraft, designed to study the structure and characteristics of radiation belts, were launched into a highly elliptical near-equatorial orbit. Russian equipment for measuring flows of energetic charged particles operates on Russian meteorological satellites of the Meteor-M (low-orbit) and Electro-L (geostationary) series. There is also a number of artificial Earth satellites (AES), including small spacecraft that carry out such measurements.

Thus, the current state of both experimental studies of the particle fluxes of the Earth’s radiation belts (RPZs) and the empirical models currently used to reduce the radiation risk of space missions shows their fundamental limitation in terms of applying operational, close to real time to the task, reduction of radiation risk and timely warning of significant temporal variations in particle fluxes.

Another aspect of this problem is that experimental studies of RPZs on one spacecraft make it possible to assess the radiation situation directly in the area of its localization at the current moment of time, but not in the entire area of near-Earth space filled with RPZs.

In a quasi-dipole magnetic field, trapped particles move along spiral paths along magnetic lines of force between the "reflection points" with the same value of magnetic field B induction in the Northern and Southern magnetic hemispheres, and drift perpendicular to the plane of the magnetic meridian, forming the so-called magnetic drift shells described by the Mc Ilvine parameter L (approximately equal to the distance from the center of the dipole to the magnetic field line in the plane of the magnetic equator) (Fig. 1). The dependence F (B) of the particle fluxes on a given L-shell on the magnitude of the magnetic field induction B is called the "high-altitude course" of the fluxes. Altitude variation is also associated with the pitch-angle distribution F ₀ (α ₀ ) of particle fluxes at the magnetic equator by Liouville's theorem.

To build a 3-dimensional picture of the current distribution of proton and electron fluxes in a significant region of the Earth’s radiation belts, measurements are needed covering a wider range of L-shells (preferably up to L = 5-7, i.e., to GPS / GLONASS or geostationary orbits), and for each L-shell - allowing to reconstruct the altitudinal course of particle flows at a given time.

A known method of conducting such measurements is the “scanning” of pitch angles with a narrowly focused detector due to the rotation of the spacecraft. Moreover, to cover the entire range of values of pitch angles, including small angles, it is required that the axis of rotation of the spacecraft be directed perpendicular to the magnetic field induction vector.

Theoretically, having accurate data on the pitch-angle distribution, it is possible to accurately calculate the fluxes along the entire length of the L-shell in the region of large values of the magnetic field B, i.e. lower heights, or large values of geomagnetic latitude. The best measurements are near the magnetic equator, because they will allow you to reconstruct the altitude course almost completely. If such measurements are not available, measurements at mid-latitudes are acceptable. In this case, for lower values of B, one can use extrapolation of the altitude course according to a power law.

Measurements of the pitch-angular distribution of fluxes near equatorial high elliptical orbits were carried out on the NASA Explorer-45 and RBSP / VanAllenProbes satellites. Two Van Allen Probes satellites, launched in 2012 into orbit with altitudes of perigee and apogee ≈700 and 30,000 km and an inclination of ≈10 °, are designed to study RPGs. These satellites have several detectors that measure the fluxes of electrons with energies from 20 keV to> 50 MeV and protons with energies from 20 keV to> 200 MeV, as well as detectors of plasma, magnetic and electric fields and waves. Measurements of the pitch-angular distribution of particle fluxes are provided by the rotation of these satellites with a period of ≈11 s around an axis directed to the Sun, i.e. almost perpendicular to the magnetic field induction vector. The pitch angle resolution in measurements of RPZ particle fluxes on these satellites is 11–16 °. The angle of the telescope aperture of the spectrometers of energetic particles is ≈20 °.

However, this method of monitoring the radiation situation has a number of disadvantages:

- The high cost of launching a satellite into a high apogee orbit. It is possible to launch such a satellite as a passing load when the main load is put into geo-transitional orbit, but for high-latitude cosmodromes, correction of the orbit plane will be required.

- A large period of circulation. For the VanAllenprobes spacecraft, the orbit period is 9 hours. Given the presence of 2 spacecraft in the same orbit in opposite phases, the period of “scanning” of radiation belts is ≈4.5 hours.

The main drawback is the need for extremely accurate pitch-angle measurements, in particular, in order to accurately calculate the particle fluxes of the outer belt at low altitudes (and at the same time, sufficient statistics for particle registration).

An analysis of the manifestations of transient atmospheric phenomena shows the relevance of developing methods for their space monitoring observed in the upper atmosphere of the Earth, which can pose a potential threat to suborbital flights of aircraft. To obtain a complete picture of the development of thunderstorms (preliminary breakdowns in the clouds, compact intracloud discharges, leader propagation, back strike, response of the upper atmosphere: elves, sprites, jets), it is necessary to conduct measurements in a wide field of view with a high temporal resolution and in a monitoring mode, t .e. continuously.

It is important to note that for a comprehensive study and monitoring of vigorous atmospheric processes, it should be carried out by a complex of equipment that registers electromagnetic radiation in different wavelength ranges: UV, visible, IR, x-ray and gamma.

Bursts of gamma radiation from the Earth’s atmosphere and the accompanying streams of relativistic electrons in near-Earth space can pose a potential danger as a natural factor of the damaging effect on technical (mainly electronic) systems and people at altitudes above the cloud cover, i.e. a few km. Gamma-ray bursts of astrophysical origin, both cosmological and related to processes in neutron stars, are very diverse in their phenomenological characteristics. Their nature is not fully understood and requires further study. Some astrophysical gamma-ray bursts can have a very high intensity and have a significant effect on the state of the upper atmosphere and ionosphere of the Earth. In this regard, they can be considered as potentially dangerous phenomena and therefore monitor observations of these phenomena are necessary.

Thus, from the foregoing, it can be concluded that the main natural and man-made risk factors that limit or pose a threat to space automatic and manned space missions in near-Earth space are cosmic radiation. In the upper atmosphere for suborbital flights of flying vehicles, risk factors are such natural transient electromagnetic phenomena associated with a significant release of energy.

The determination of current radiation loads in real time is not only expedient, but also necessary, because in conditions of rapidly varying flows of ionizing radiation in near-Earth space, the timely generation of alert signals of radiation hazard for specific spacecraft can reduce the radiation risk by, for example, transferring the spacecraft onboard systems to “sleep mode”. For most types of temporary variations in the fluxes of particles of the Earth’s radiation belts, times from minutes to hours are characteristic of periods of increased magnetic activity (magnetic storms). Approximately such times are characteristic of fast fronts of the fluxes of solar energetic particles reaching the vicinity of the Earth. It is in this range that the optimal time for generating alert signals should be located to prevent or reduce undesirable effects from emergency situations on the spacecraft.

Implementation of a large-scale monitoring system for several spacecraft of electromagnetic transients in the upper atmosphere will allow us to identify local areas of their most intense generation on a shorter time scale than can be monitored on a separate spacecraft and, thereby, increase the reliability of their forecast when planning suborbital flights.

Devices designed to register electromagnetic transients in the gamma range can simultaneously be used to monitor radioactive "space debris" - the remnants of spacecraft with nuclear facilities or radioactive sources on board. Therefore, this task is also de facto present in the monitoring program for potentially dangerous objects.

Several technical solutions are known for the creation of space threat monitoring systems.

A close technical solution for the composition and purpose of the multi-satellite monitoring system is described in patent RU 2576643 “Satellite system with ultra-high solar-synchronous orbit”. In patent RU 2535375, “A method for observing a planetary surface from outer space and a space satellite system for implementing this method,” a method for constructing spacecraft constellations for monitoring the Earth’s surface is proposed. The orbits of the devices are supposed to be selected circular with different heights for devices with different inclination. With the described construction, the structure of the satellite system is maintained. A known method described in the patent RU 2576643 for creating a satellite constellation for monitoring purposes in ultra-high solar-synchronous orbit is known. The difference of this system is that it provides the ability to cool telescopes that require cryogenic temperatures, with lower costs. Close to the described satellite system, the solution according to patent RU 2360848 "Multipurpose satellite system". This invention describes spacecraft launched into orbits at various altitudes and performing various tasks, including meteorological and radar observations. The apparatus system includes high elliptical and low altitude satellites. A feature of the system is increased reliability and better service in the Arctic and subarctic regions.

Also known technical solutions for patents US 9647749 "Satellite constellation", US 6868316 "Satellite constellation system" and US 6009306 "Hub communications satellite and system", which contain a description of the groupings of spacecraft. The purpose of such groups is to monitor the Earth’s atmosphere from space, but the main task of such systems is telecommunications and data broadcasting.

US8511614, "Satellite system providing optimal space situational awareness", describes a method for monitoring objects in near-Earth space against the background of the Earth’s surface, against the background of sun glare from the Earth’s surface and against the background of the starry sky using a group of specialized satellites. In particular, it is proposed to place at least one such satellite in an orbit ~ 400 km high, and the second - in an orbit ~ 1400-1600 km high, and monitor using an electromagnetic radiation detector at a wavelength of 200-300 nm. Additionally, radiation detectors in the infrared (IR) and ultraviolet (UV) spectral ranges can be used.

Known international aerospace global monitoring system (MAKSM) according to patent RU 2465729. The system is described as solving the problem of monitoring global geophysical phenomena and predicting natural and man-made disasters. The system is built on the basis of small and microsatellites and also includes aviation and ground levels.

A patent application is known for US 2014/0027576, in which by placing several spacecraft in one orbit, you can reduce the time shift of the equatorial intersection, as described in the background, to an arbitrary level. For example, with 90 spacecraft in 90-minute orbits, the Earth will turn east for 1 minute between satellite transitions. If the field of view of the instruments on board the spacecraft is equal in width to the distance by which the Earth rotates during this time (27.8 km at the equator, in the case of a 1-minute separation), then the instruments together will be able to image the entire Earth, with an increase in overlap to the poles due to the spherical nature of the Earth. In the case of the Earth imaging system, the optical device could either take individual image frames with the appropriate interval or continuous video. The result is a complete recording of the latitude band by the entire constellation in one given case or registration of a sinusoidal ground track with one spacecraft, which returns to the same latitude every 90 minutes, and at the same location on Earth every day.

It should be noted that at present, the approach to the formation of multisatellite groups based on the standard CubeSat construct is most actively developing. According to NORAD at the beginning of 2017, more than 250 orbital objects with characteristics corresponding to this construct were registered. Moreover, the vast majority of these satellites are in circular orbits with a low degree of ellipticity and are highly specialized [Power Budgets for CubeSat Radios to Support Ground Communications and Inter-Satellite Links / O. Popescu // IEEE Access, 2017, DOI 10.1109 / ACCESS.2017.2721948] . Using the CubeSat construct promotes the development of multi-satellite missions. However, a significant drawback of this standard is the limited ability, first of all, of energy for the installation and use of communication equipment on them, which is necessary both for transmitting the measurement data collected by the scientific devices installed on them and related auxiliary information, including the exchange of synchronization signals, etc. .P. For this reason, there are only three options for building a multi-satellite constellation: a linear satellite group, a satellite cluster and a constellation satellite group [Survey of Inter-satellite Communication for Small Satellite Systems: Physical Layer to Network Layer View / R. Radhakrishnan, WW Edmonson, F. Afghah, RM Rodriguez-Osorio, F. Pinto, and SC Burleigh // IEEE Communications Surveys & Tutorials - 2016-vol. 18, no 4 - p. 2442-2473].

Closest to the claimed is a method of monitoring potentially dangerous phenomena in near-Earth orbit using several small spacecraft (SC), described in the article Panasyuk MI, Podzolko MV, Kovtyukh A.S. et al. “Operational radiation monitoring in near-Earth space based on the multi-tiered grouping of small spacecraft”, Space Research, 2015, v. 53, No. 6, pp. 461-468 (prototype), which presents a variant of the global radiation monitoring system in near-Earth space based on a multi-tiered grouping of small spacecraft. The considered constellation of satellites with identical radiation equipment will provide operational information about the fluxes of electrons and protons of the Earth’s radiation belts and solar cosmic rays, which will allow reproducing three-dimensional pictures of the distribution of particle fluxes in real time. According to this method, the radiation situation is monitored using a satellite constellation, which includes 3 devices with the same instrumentation, located in circular orbits with altitudes of 650, 1700 and 8000 km and inclinations of 80 °, 77 ° and 60 °, respectively, or one spacecraft, located in a high elliptical orbit having perigee and apogee heights of 700 and 8000 km, the perigee argument is 310 °, the inclination is 63.435 °.

The principal disadvantage of the method for monitoring potentially dangerous phenomena in near-Earth orbit by this method is that, in the embodiment using only one spacecraft in a high elliptical orbit, it will not provide a high degree of updating the results of monitoring the radiation situation due to the longer duration of its orbit compared with low-orbit satellites , which is important, since most of the spacecraft, including manned missions, are carried out at altitudes not higher than 500 km. And in the version with three satellites with a high circular orbit of the third spacecraft, in addition, the speed of their intersection of L-shells with a high L value will be up to three times higher than for a satellite in a high elliptical orbit with apogee at the same altitudes, which significantly reduces the accuracy monitoring the radiation situation. These methods do not allow the assessment of radiation monitoring to quickly identify space threats in real time in the entire area of near-Earth space filled with RPGs.

Disclosure of Invention

The technical problem solved by the claimed invention is the creation of a method devoid of the disadvantages inherent in the above analogues.

The technical result is the creation of an orbital constellation of satellites and / or spacecraft equipped with a complex of scientific equipment that provides the ability to quickly (in a mode close to "real time") monitor ionizing radiation (fluxes of energetic charged particles) in a significant region of the near-Earth space, detect electromagnetic transient phenomena , with the identification of various space threats, including the determination of the levels of radiation loads created by ionizing radiation - particles of radiation Earth’s oases and energetic solar particles invading the magnetosphere not only in the orbits of the satellites or the spacecraft themselves, but also in the entire region of captured radiation, up to the geostationary orbits of the spacecraft.

The inventive method allows you to quickly in a mode close to real time, to determine the radiation risk and to warn in a timely manner of significant temporal variations in particle fluxes, to assess the radiation situation in the entire region of the near-Earth space filled with RPG, i.e. carry out measurements of omnidirectional particle fluxes at different points of the L-shell at different heights with a given discreteness in time. The claimed method for monitoring the radiation situation also involves measuring at each point the magnitude and direction of the Earth’s magnetic field B.

To implement the invention, small satellites can be used to reduce the cost of the satellites themselves and put them into orbits. In this case, a space grouping can be used, i.e. sharing measurements of several satellites simultaneously in orbits and ground-based measurements and data processing; for radiation monitoring - ground-based data processing and building a picture of the current spatial distribution of fluxes of energetic particles in a significant region of near-Earth space.

The specified technical result is achieved due to the formation of a certain orbital constellation of spacecraft that provides the most continuous monitoring of potentially dangerous threats at various points in the near-Earth space (radiation conditions, as well as electromagnetic transients - cosmic and atmospheric gamma-ray bursts, bursts of optical and ultraviolet radiation from the Earth’s atmosphere) with continuous documentation of measurement results and, if possible, with minimum transmission intervals and terrestrial satellite data receivers.

According to the invention, a method of forming a constellation of artificial Earth satellites (AES) for monitoring potentially dangerous threats in near-Earth space equipped with spectrometric equipment includes placing at least three AES in different orbits crossing the L-shells of the Earth’s radiation belts at different points at different at the same time, at least two circular orbits are used - a low solar-synchronous orbit with a height of 500-650 km and an inclination of 97-98 °, and an orbit close to a circular one with a height of 1400-1500 km an inclination of about 80 °; and at least one elliptical orbit with an apogee of 8000 km, a perigee of 600-700 km and an inclination of ~ 63.4 °; at the same time, the orbits are selected so that the departure of the perigee argument of the orbit is less than 3-4 deg./year.

When placing more than one satellite in one orbit, an orbital structure is formed with a uniform distribution of the satellite in orbit as possible.

Particle and radiation spectrometers, including a spectrometer of energetic protons and electrons, containing several semiconductor telescopes with different spatial orientations of their axes are used as spectrometric equipment for monitoring the radiation situation: the axes of all telescopes, except one, are oriented in the plane of the magnetic meridian, and one telescope - perpendicular to this plane.

Spectrometric equipment for monitoring the radiation situation is installed on all satellites of the satellite constellation, while the satellites installed in circular orbits additionally place equipment for monitoring electromagnetic transients - cosmic and atmospheric gamma-ray bursts and bursts of optical and ultraviolet radiation from the Earth's atmosphere.

Spectrometric equipment for monitoring the radiation environment includes a proton spectrometer in the energy range from 1 to> 160 MeV and electrons in the energy range from 0.15 to 10 MeV.

Spectrometric equipment for monitoring the radiation situation includes a 3-component magnetometer, with the ability to measure magnetic field variations at frequencies up to 100 Hz.

As spectrometric equipment for monitoring electromagnetic transients, three wide-directional scintillation foswich gamma-ray scintillation detectors in the range of 10-3000 keV, the axes of which are located in mutually perpendicular directions, and a track gamma-ray spectrometer with a recorded energy range of no worse than 50-5000 keV, angular resolution of at least ~ 6 °, field of view of at least ± 25 ° degrees. The main axis of the detector block and track gamma spectrometer is oriented to nadir.

As a spectrometric equipment for monitoring electromagnetic transients, a spatially sensitive spectrometer with UV and IR radiation detectors directed to a nadir is used.

The technical result is also achieved in a method for monitoring potentially dangerous threats in near-Earth space, including the formation of a constellation of artificial earth satellites (AES) according to claim 1, with a duty cycle of transmitting information to Earth, preferably at least 0.5-4 hours, depending on the orbit, transmission and processing of measured data in the ground processing center. Spectrometric equipment located on various satellites is synchronized with reference to the unified world time with an accuracy of at least 3-5 μs.

Brief Description of the Drawings

The group of inventions is illustrated by drawings.

In FIG. 1 shows a schematic view of the L-shells L = 2, 3, and 4 in the plane of the magnetic meridian and the motion of the captured particles.

In FIG. Figure 2 shows the dependences of the magnitude of the magnetic field induction of the Earth B at the intersection of the magnetic shells L = 4 (solid lines) and L = 6 (dashed) in circular orbits with a height of 8000 km and inclinations of 60 ° (thin lines) and 45 ° (thick lines) at different longitudes in the northern (upper graph) and southern (lower graph) hemispheres.

In FIG. Figure 3 shows the projection of an elliptical orbit with altitudes of perigee and apogee ≈600-700 and 8000 km, an inclination of 63.4 ° and an argument of perigee ≈310 ° on the plane of the magnetic meridian. Shown are the L-shells L = 1.6, 2, 3, 4, 5, 6, 7.

In FIG. Figure 4 shows the maximum (smooth curves) and average (dotted) values of the step in L at a time step of 5 seconds for orbits, from top to bottom: 1) circular orbit h = 650 km, i = 80 °; 2) circular h = 1700 km, i = 77 °; 3) elliptical h _n = 700 km, h _a = 8000 km, i = 63.4 °, ω = 310 ° (at low altitudes B> 0.1 G).

In FIG. 5 is a schematic representation of the relative position of the orbits of the constellation of small satellites.

In FIG. 6 shows the orientation options of the telescopes:

in Fig. 6a, the axes 3 of the telescopes are oriented along the axes of a rectangular Cartesian coordinate system, the axis of the 4th — along the main diagonal of the cube, built on the axes of the first three. The telescope aperture angle is 60 °.

in FIG. 6b, the axis of the main telescope is perpendicular to the plane of the magnetic meridian; the axes of several additional detectors lie in the plane of the magnetic meridian. The aperture angle of the telescopes is 35-45 °.

DETAILED DESCRIPTION OF THE INVENTION

Awareness of the importance of the problem of monitoring hazardous factors in near-Earth space (“space threats”) and the need for a systematic solution to create a warning system about their potential danger to spacecraft (SC) was the initial prerequisite for the selection and justification of the technical solution presented by the present invention.

The proposed monitoring method in near-Earth space allows you to build a space system for monitoring and preventing space threats for both ongoing and planned space missions, including high-altitude atmospheric aircraft.

The main task solved by the present invention is to carry out on-line (in a mode close to “real time”) monitoring of charged particle fluxes in near-Earth space at relatively low altitudes with an accuracy and volume sufficient to enable 3- reconstruction of the known empirical models a dimensional picture of the current distribution of fluxes of energetic protons and electrons in a significant area of the Earth’s radiation belts and based on it - current radiation conditions for a large range of satellites orbits .

высоты для внешнего радиационного пояса экстраполяцией высотного хода по степенному закону.To cover a large range of L-shells, an elliptical orbit with a significantly lower apogee height, for example, ≈8000 km, but with a higher inclination, can also be used. Such an orbit has a shorter period and requires lower energy costs for launching a satellite. Monitoring of the radiation situation carried out by measurements in this case will make it possible to obtain measurement data, on the basis of which it is possible to recalculate the fluxes to

heights for the external radiation belt by extrapolating the altitude course according to a power law.

The method allows the measurement of omnidirectional particle fluxes at different points of the L-shell at different heights with a given discreteness in time. The claimed method for monitoring the radiation situation also includes measuring at each point the magnitude and direction of the Earth’s magnetic field B, for which a 3-component magnetometer is used.

The results of such monitoring resulting from such monitoring are then transmitted via standard communication channels to ground receiving stations and then to software and hardware for subsequent calculation of the flow altitude for the entire L-shell by interpolating and extrapolating the measurement data using any known theoretical and empirical laws.

разрешение проводимых измерений. При этих условиях проводимый мониторинг радиационной обстановки на основе измерений в достаточно ограниченном числе точек вдоль траекторий ИСЗ спутниковой группировки позволяет оптимальным образом решить поставленную техническую задачу повышения полноты результатов при их обновляемости в режиме, близком к режиму реального времени в масштабе характерных скоростей ее изменений.The task of operational monitoring of the radiation situation involves the use of a limited number of satellites and high, as far as possible,

resolution of measurements. Under these conditions, monitoring of the radiation situation based on measurements at a fairly limited number of points along the satellite satellite trajectories allows us to optimally solve the formulated technical problem of increasing the completeness of the results when they are updated in a mode close to real-time mode at the scale of its characteristic rates of change.

The results of measurements of the fluxes of energetic particles obtained as a result of monitoring the radiation environment can then be used to reconstruct a three-dimensional picture of the spatial distribution of particle fluxes over the entire range of heights up to the heights of stable capture of charged particles by the Earth’s magnetic field, using well-known and promising models for approximating the altitude course of radiation fluxes of particles belts.

высотах вплоть до минимального значения B₀ на геомагнитном экваторе. При этом пересечению орбиты и L-оболочки соответствует не единственное значение магнитной индукции В, а разные значения в некотором интервале на разных витках, из-за асимметрии магнитного поля относительно центра Земли. Указанное условие реализуется при использовании для мониторинга радиационной обстановки по меньшей мере трех ИСЗ на орбитах с высотами ~500-650 км, ~1400-1700 км и >7000-8000 км.According to the method of the present invention, the heights of the orbits of spacecraft are formed in such a way that they intersect the L-shells in three regions where there is a different nature of the altitudinal course of the flows: in the region of a sharp “blockage” of the altitude course at low altitudes h _min (L, В) <1000 km; some transitional region of the "knee"; regions of a slow, close to power-law change in particle fluxes on

heights up to the minimum value of B ₀ at the geomagnetic equator. In this case, the intersection of the orbit and the L-shell corresponds not to a single value of magnetic induction B, but to different values in a certain interval at different turns, due to the asymmetry of the magnetic field relative to the center of the Earth. The indicated condition is realized when at least three satellites are used for monitoring the radiation situation in orbits with altitudes of ~ 500-650 km, ~ 1400-1700 km, and> 7000-8000 km.

The expediency of limiting from above the orbit height h≤8000 km is due, inter alia, to the operability of the satellite’s spatial orientation system and to a reasonable limit in terms of complexity and cost of launch, the orbit period, and others. The limitation from below h≥500 km is chosen to knowingly exclude the influence of the atmosphere on satellite motion.

Various values of the orbital inclination were analyzed. With less inclination, the temporal resolution of the measurements is higher, but, depending on the turn, the covered range of L-shells is smaller. In this case, the criterion for selecting the inclination was taken as follows: the spacecraft must pass through its maximum L = 4 at each intersection of the outer electron belt. As an example, in FIG. Figure 2 shows the values of B when they intersect in circular orbits with a height of 8000 km and inclinations 60 and 45 ° of the magnetic shells L = 4 and 6 at different longitudes. As can be seen from FIG. 2, the satellite in an orbit with an altitude of 8000 km with an inclination of 45 ° will be significantly worse than “seeing” the external radiation belt compared to the satellite in an orbit with an inclination of 60 °. It is also important to note that for the radiation monitoring problem, the inclination of the circular orbits i and (180 ° -i) are equivalent. As a result, orbits 1 and 2 with altitudes of ≈500-650 and 1400-1700 km can be chosen with close inclinations, for example, solar-synchronous or close to them. For the third satellite, a grouping of satellites with an orbit of up to 8000 km is proposed to use instead of a circular elliptical orbit with heights of perigee and apogee ≈700 and 8000 km, an inclination of 63.435 °, a perigee argument of 310 ° and a period of ≈3 hours. Such an orbit and its projection onto the plane of the magnetic meridian on different L-shells is shown in FIG. 3. This orbit for each L-shell intersects all three areas indicated above, where a different character of the altitudinal course of the flows of energetic charged particles is observed. In this case, on each orbit, the spacecraft will intersect the L-shells at 2-4 different points. After the satellite crosses in this orbit of a given L-shell, the maximum time until it crosses again at the same height is equal to the orbit period, i.e. 3 hours. For circular orbits, this time is ≤1 / 2 of the orbit period, that is, for an orbit 1700 km high - ≤1 hours, for an orbit 650 km high - ≤50 minutes (for the outer belt; the inner belt will intersect only in the South Atlantic anomalies, but the flows in the inner belt are more stable than in the outer). Moreover, for low circular orbits, satellite satellite launches are possible.

The orbital inclination of a high-orbit satellite with an orbit height of up to 8000 km is chosen equal to the “critical” value of 63.435 °, at which there is no departure of the perigee argument due to the influence of the 2nd zonal harmonic of the Earth’s gravitational potential. The speed of this departure is mainly determined by the 2nd zonal harmonic of the Earth’s gravitational potential, which is responsible for the “flattening” of the Earth along the axis of its rotation, and is described by the formula:

dω / dt = 4.982⋅ (R _З / a ) ^3.5 (1-e ² ) ^-2 (5cos ² i-1), degrees / day

where R _З is the average radius of the Earth, a is the semimajor axis of the orbit, e is the eccentricity, i is the inclination.

In this case, it is necessary to ensure the accuracy of the inclination of the orbit when the satellite is withdrawn within ≤0.1-0.2 °. With a more significant error in the inclination, for example, by 0.5 ° from the “critical” value for an elliptical orbit with the indicated parameters, the perigee angular distance drift speed will be 0.035 degrees / day, or ≈13 degrees / year. Thus, the orbit noticeably evolves over the lifetime of the satellite (≥3 years). For radiation monitoring tasks, it is desirable that the departure of the perigee argument of the orbit be <3-4 deg./year. When outputting using the booster unit, obviously, the required accuracy can be ensured. Also, harmonics of the Earth’s gravitational potential will be affected by higher order harmonics and the Moon and Sun’s gravity, but to a much lesser extent.

An analysis of the spatial resolution of the measurements in the considered orbits is illustrated in FIG. 4, which shows the measurement step along L at a time step of 5 seconds in circular orbits with an altitude of 650 and 1700 km and an inclination of 80 and 77 ° and an elliptical orbit with altitudes of perigee and apogee 700 and 8000 km, an inclination of 63.4 ° and an argument of perigee 310 ° (at low altitudes B> 0.1 G; at B> 0.1 G, the step is several times smaller). As can be seen from the graphs in FIG. 4, depending on the orbit on L≤7, the maximum step ΔL <0.18-0.35, on L≤4 the step ΔL <0.8-0.16; average values are still 2-3 times lower.

Thus, for the indicated orbits, the time step of ≈5 seconds provides the necessary spatial resolution of the measurements; at the same time, this step allows one to obtain sufficient statistics on the registration of particle flows.

Thus, for monitoring with improved completeness of the description of the radiation environment of measurements, it is advisable to use the satellite constellation in orbits with different heights, ellipticity, the position of the orbit planes and in different phases of orbital motion. The number of spacecraft (SC) in the constellation is preferably at least three, with SC No. 1 being placed in a low sun-synchronous orbit with an altitude of 500-650 km and an inclination of 97-98 °, SC No. 2 is placed in an orbit close to circular with a height of 1400 -1500 km and an inclination of ~ 80 °, spacecraft No. 3 is placed in an elliptical orbit with an apogee of 8000 km, a perigee of 600-700 km and an inclination of 63.4 °. A schematic representation of the orbits of such a constellation of satellites is shown in FIG. 5.

The claimed solution allows the measurement of omnidirectional fluxes of energetic protons and electrons. The method of the present invention provides for the separate registration of the fluxes of these particles and the measurement of their energy spectra, since the free paths (penetrating ability) and the associated radiation effects are different for particles of different types and energies.

A typical design of a spectrometer of energetic protons and electrons is an assembly of the "telescope" type, including several semiconductor and scintillation detectors of different thicknesses, located one below the other on a single axis. Charged particles, passing through the entrance window of the telescope and entering the detector, emit energy in it, which is converted into an electrical impulse by a value proportional to the released energy. The device also contains electronic logical selection systems that operate on the principle of coincidence and anticoincidence of electrical impulses. An assembly of several detectors and electronic logic circuits operating on the principle of coincidence-anti-coincidence of pulses from different detectors make it possible to determine the particle type (electron, proton), its energy, and partially filter out the lateral passage of particles (through the telescope body).

However, such a device has a limited viewing angle. The reason is that the energy released from a particle of a given type and the energy in the detector varies depending on its path length in the detector material (this is true for scintillation and semiconductor detectors), which in turn depends on the angle of the particle through the detector. As a result, with an increase in the possible range of angles, the accuracy of determining the type and energy of particles will decrease. The maximum practical value of the telescope aperture angle is ≈60 °.

According to the method of the present invention, the measurement of omnidirectional particle fluxes is made by several "telescopes" whose axes are oriented at different angles to the magnetic field induction vector B. Moreover, the axis of at least one of the detectors at each point in the orbit must be directed at an angle to the magnetic field induction vector close to 90 °. In this case, such measurements then allow, when processing the measurement results by ground-based software and hardware, to approximate the pitch-angular distribution of particle flows and the omnidirectional flow. In contrast to analogs (Van Allen Probes spacecraft), very high accuracy of pitch-angle measurements is not required, especially in the area of small pitch-angles. Since the flux of electrons and protons of radiation belts is determined mainly by particle fluxes with large pitch angles. At the same time, for measurements it is advisable to limit ourselves to a reasonable number of telescopes, for example, ≤4-5, in order to avoid an unjustified increase in the mass of the spacecraft and the complexity of onboard logic devices. In FIG. 6 schematically shows some possible options for the orientation of telescopes. In FIG. 6a shows the first option, which provides for the orientation of the axes of 3 telescopes along the coordinate axes of a rectangular Cartesian system, and the axes of the fourth along the main diagonal of the cube built on the axes of the first three (the angles between this axis and the axes of the other 3 detectors are 54.7 °). With this orientation of the telescopes for any orientation of the spacecraft, in the worst case, we will have flow measurements for 2 different pitch angles, and in most cases for ≥3 different pitch angles, which allows us to solve the stated technical monitoring problem, since the results of such The measurements completely describe the omnidirectional flow with satisfactory accuracy even for large values of the telescope viewing angle of ~ 60 °.

According to another possible embodiment of the spectrometer shown in FIG. 6b, it is necessary to have a system of active 3-axis magnetic orientation of the spacecraft. In this embodiment, the main telescope is directed perpendicular to the plane of the magnetic meridian, as a result, this telescope gives measurements for pitch angles in the vicinity of 90 °. The axes of several additional telescopes lie in the plane of the magnetic meridian and give measurements for other pitch angles. The angle of view for all detectors in this embodiment can be equal to 35-45 °.

углом обзора ≈60°.Monitoring of radiation conditions is very important for ensuring the safety of space missions, both manned and robotic, electronic devices of which can be damaged in the event of adverse radiation conditions and which in these circumstances should be put into a passive mode of operation. However, no less important for this purpose it is also necessary to monitor gamma-ray bursts of atmospheric galactic origin. Satellite observations of transient phenomena in the Earth’s atmosphere require a low orbit. Thus, the satellite constellation should include a satellite in an orbit <1000 km in height, which will be entrusted with the tasks of monitoring transient phenomena. Satellite observations of atmospheric transient phenomena can be carried out only on the night side of the Earth and require the orientation of the satellite to the Earth ("in nadir"). In addition, the task of radiation monitoring requires, at a minimum, that the axis of one of the detectors of energetic protons and electrons be directed at an angle to the magnetic field induction vector close to 90 °. A solar-synchronous orbit with a local time of ≈3 and 15 hours satisfies all these requirements, the satellite on which will have the orientation of the 1st axis to nadir and the 2nd axis perpendicular to the plane of the geographic meridian. In this case, the UV / X-ray / gamma radiation detectors will be directed to the nadir, the detector of energetic protons and electrons - perpendicular to the plane of the geographic meridian, therefore, at an angle to the magnetic field line close to 90 °. Since at low altitudes there are significant angles of the loss cone, for example, for a near-polar orbit with a height of 650 km, the angle of the loss cone (the range of pitch angles at a given point for which the fluxes of captured particles are 0) is> 50 °, for measuring omnidirectional fluxes in such an orbit, it is sufficient to use one such telescope, possibly with

viewing angle ≈60 °.

According to the monitoring method of the present invention, the results of measurements of each satellite should be transmitted to Earth with the highest achievable efficiency (good value - tens of minutes; satisfactory - 1-3 hours) through satellite data transmission systems or a network of ground-based data receiving stations.

Transmitted data includes:

- the next cutoff of the measurement time;

- coordinates of the corresponding orbit point;

- for each telescope of the spectrometer of energetic protons and electrons - a set of counting rates, [particles / second], proton and electron fluxes for a given set of energy intervals;

- measurement results of a 3-coordinate magnetometer;

- data on the orientation of the satellite (the last 2 parameters are desirable to have with an accuracy of ≈1 °).

So, according to the invention, the composition of the constellation of small satellites should include at least three spacecraft:

• The first spacecraft, in a low circular polar orbit, carrying scientific equipment for near-Earth space monitoring (OKP) in the optical, x-ray and soft gamma ranges, as well as equipment for recording charged particles of cosmic radiation and an alternating electromagnetic field;

• The second spacecraft, in an elliptical orbit with an apogee height of at least 8000 km, carrying equipment for recording charged particles of cosmic radiation and an alternating electromagnetic field, as well as other devices;

• The third spacecraft, in a circular or elliptical orbit, the composition of scientific equipment is identical to KA1 or KA2.

The satellite constellation diagram implementing the proposed method is shown in FIG. 5.

When implementing the method, the scientific instruments of the complex should work in the main (standby) mode, automatically responding to the interesting ("trigger") phenomena. The minimum adjustment of instrument parameters in flight during flight tests will be necessary to balance the volume of accumulated information from instruments by adjusting triggers, sensitivity and response thresholds, duty cycle of recording events, etc. The modular structure of the equipment complex allows you to adjust the amount of accumulated information within two orders of magnitude, to shift the focus of the devices depending on the environment, the state of the complex, the results of the analysis of the data and other circumstances. This principle of equipment control was developed at the Lomonosov spacecraft.

From the point of view of information logistics, the data accumulated by devices are divided into the following groups:

• Continuous monitoring information analyzed on the Earth in semi-automatic / automatic modes as they become available. Estimated frequency of obtaining such information is 1 time per day. Frequency can be reduced for a limited time without disrupting a scientific task. The main limitation on the discharge of data of this type is the capacity of the storage device (memory) and the buffer memory of the target information radio link (RLCI).

• Operational monitoring information on the state of the radiation belts of the Earth and the near magnetosphere. The frequency of obtaining this information on Earth should not fall less than 4 times per hour (the number of times the spacecraft crosses the Earth’s radiation belts in a low circular polar orbit). The functioning of a three-dimensional model of near-Earth radiation (one of the main objectives of the project) depends on the regularity of obtaining this information.

• Telemetric information transmitted to the service platform of the spacecraft (SP KA). This information allows you to quickly assess the state of the scientific complex systems, control operating modes, basic settings, current volumes of accumulated information and other important parameters. It is transmitted in the spacecraft telemetry volume (spacecraft TM) during spacecraft control sessions. The volume and frequency of receipt of telemetric frames are additionally agreed.

• General telemetry information of the scientific complex. Includes detailed logs of work, exchanges on the command and telemetric buses, results of self-diagnostics of devices, detailed settings, etc. The average daily volume does not exceed 100 MB. Information is transmitted with monitoring information on the RLCI as part of the staffing schedule of communication sessions.

In addition, the method provides for the possibility of periodically downloading from the Earth data consisting of:

• instrument software updates;

• changed and refined settings;

• additional information received, including from other spacecraft of the system, formed on Earth in the sector of target planning of the system.

The main connecting element of the spacecraft system is the exact binding of the onboard time scale (BSW) of the spacecraft scientific equipment complexes to the world time scale. The accuracy of the timing provides the spatial localization of the observed events, the mutual linking of the accumulated data, the ability to quickly triangulate the observed objects (for potentially dangerous bodies and space debris). The accuracy of the BWA KNA reference to world time, taking into account the clock pulses issued to the devices, should not be worse than 3-5 μs.

The main criteria for choosing a system:

• accessibility for general civilian use for scientific purposes, purchase and use in the Russian Federation;

• the price of the transmitter (transceiver) in conjunction with the cost of services on the Earth and in flight, including the cost of traffic, the cost of attracting ground funds, etc .;

• simplicity of the use process (the need to re-target the antenna, monitor the communications center, the number and volume of ground-based assets involved, additional requirements placed on the spacecraft, etc.);

• coverage area (percentage of the orbit where regular stable communication is possible);

• exchange rate and channel width.

Either one of the commercial satellite communications systems or the newly created network of ground-based VHF stations scattered at different longitudes can be used as possible operational control systems (JMA).

As the main ground link, the equipment of the target planning sector of the Research Institute of Nuclear Physics of Moscow State University and the Center for Operational Space Monitoring Data (CDCM) of Moscow State University are used. These nodes in automatic and semi-automatic mode will allow for the targeted use of equipment, receipt, processing and analysis of data, including telemetry, their archiving, storage and distribution to users.

Despite the heterogeneity of the technical tasks of monitoring potentially dangerous objects in space, combining them within the framework of a “single space platform” seems expedient in comparison with projects aimed at monitoring only one of the dangerous space factors, since the onboard computing a complex designed for on-board information processing is technically and economically optimal to create for a complex of instruments on the same spacecraft platform than on different And for selected "unidirectional" target devices. That is why it becomes possible to combine individual detectors into a single system with the goal of implementing a "budget" project, implemented on the basis of "small spacecraft" with a total weight not exceeding 100 kg. In addition, the implementation of such a project scheme makes it possible to relatively simplify the complexity of the ground-based segment for managing and receiving information compared to "distributed" projects that perform monitoring tasks of only one of the dangerous space factors. Thus, the present invention and the multi-orbit satellite constellation that implements the proposed monitoring method makes it possible in the future to create a universal platform for multifunction missions for various purposes.

An example embodiment of the invention

The constellation of small satellites for monitoring space threats to monitor potentially dangerous phenomena includes several small spacecraft (SC).

In the minimum version, a grouping of three spacecraft was used: spacecraft No. 1 is placed in a low sun-synchronous orbit with an altitude of 500-650 km and an inclination of 97-98 °, spacecraft No. 2 is launched into an orbit close to a circular one with an altitude of 1400-1500 km and an inclination of ~ 80 °, spacecraft No. 3 is launched into an elliptical orbit with an apogee of 8000 km, a perigee of 600-700 km and an inclination of 63.4 °. The relative position of the orbits is shown in FIG. 5.

The following instruments have been installed on satellites for space monitoring of hazardous objects and phenomena: an electron and proton spectrometer, wide-field optical cameras, a set of instruments for studying electromagnetic transient phenomena, including gamma spectrometers, UV and IR radiation detectors. At the same time, the following devices were installed on spacecraft No. 1: for monitoring space radiation, a complex of scientific equipment for studying TAJ in the optical range, a complex of scientific equipment for monitoring in the gamma range, and also a data collection unit (BSI). Each of spacecraft No. 2 and No. 3 has equipment for monitoring cosmic radiation and an optical camera with a wide field of view, a compact gamma spectrometer, and an electronics unit that communicates with the satellite's onboard systems. The BSI information collection unit has also been installed as part of scientific equipment, collecting scientific and telemetric information from individual devices and transmitting it to the on-board storage device, supplying power and commands to the devices from the on-board satellite systems.

Devices for radiation monitoring

The equipment for monitoring cosmic radiation includes a spectrometer (SPE) of protons in the energy range from 1 to> 160 MeV and electrons in the energy range of 0.15-10 MeV. Its main element is an assembly of the “telescope” type, which includes several semiconductor detectors of various thicknesses and a scintillation detector located coaxially one under the other. To measure the pitch-angular distribution of flows and omnidirectional flows of particles, several telescopes with different spatial orientations are used. An embodiment of the method is also possible, in which a layout is used in which the telescope axes must lie in the plane of the magnetic meridian (in the case of a satellite orbit close to polar, this means that they should lie practically in the orbit plane), and the axis of another telescope perpendicular to the plane of the magnetic meridian.

The above parameters of the spacecraft orbits on which radiation monitoring instruments are installed cover the entire spatial range of the existence of radiation captured in a magnetic field, i.e. radiation belts. At the same time, measurements of omnidirectional fluxes of captured particles are ensured, followed by model interpolation and extrapolation of the measured fluxes to the entire region of radiation belts in order to monitor cosmic radiation. Such measurements make it possible to calculate the current distribution of particle fluxes in a large volume of radiation belts and, as a result, the current levels of radiation loads for a wide range of operating orbits.

The equipment also uses a 3-component magnetometer.

An important addition to the space monitoring system is the fully automated ground-based satellite data operational analysis system developed at Moscow State University, designed to evaluate and predict the radiation conditions in near-Earth space (OKP) in real time (Myagkova I.N., Kalegaev V.V., Shugai Yu.S., Dovlenko S.A., Panasyuk M.I., Space Weather Analysis Center, Research Institute of Nuclear Physics, Moscow State University: Monitoring and Forecasting the State of Near-Earth Space, 13th International Scientific conference "Space, Ecology, Safety - SES1027", Sofia, Bulgaria, 2 -4 November 2017. Ed. G. Mardirossian, Ts. Srebrova, G. Jelev. ISSN: 1313-3888. Space Research and Technology Institute - Bulgarian Academy of Sciences, Sofia, Bulgaria, p. 41-47.)

The spacecraft grouping allows monitoring in a mode close to real time. To do this, it is planned to use other spacecraft (for example, the Globalstar or Gonets spacecraft, or telecommunication satellites in geostationary orbit).

Instruments for monitoring electromagnetic transients

The complex of scientific equipment for studying transient atmospheric phenomena (TAJ) in the UV and optical ranges includes a spatially sensitive spectrometer - a small lens telescope (MLT) with a high time resolution for measuring optical radiation from TAJ and lightnings and DUFIC UV and IR radiation detectors, supplemented by measurement channels in the far UV range. Spectrum measurement is necessary to determine the type and height of TAJ generation, as well as to highlight lightning discharges along a characteristic line of 777 nm and by the absence of a signal in the region of the oxygen absorption line - 762 nm). The axes of the MLT and DUFIK instruments should be oriented in nadir with 90 ° shading angles along the axes of the detectors. The MLT device consists of a wide-field lens and a position-sensitive detector in the form of a multi-anode PMT, as well as a set of photomultipliers for measuring long time series of the TAJ signal with high sensitivity and high time resolution. The design of the device provides up to 16 spectral channels.

The DUFIC device consists of three photomultipliers, the input windows of which are closed by light filters that provide operation in different spectral ranges - infrared (600-800 nm), near UV (240-400 nm), sun-blind (100-300 nm). In addition, it includes an optical detector based on a microchannel plate, which provides registration of radiation in the range from far UV to soft X-ray.

The complex of scientific equipment for monitoring in the gamma range includes three broadly directed scintillation gamma-ray detectors of the BDRG type [Amelyushkin A.M., Galkin VI, Goncharov BV et al. BDRG and SHOK instruments for studying the intrinsic emission of gamma-ray bursts on board the Lomonosov spacecraft // Cosmic. researched 2013.V. 51. No. 6. S. 478-483] for monitoring the upper atmosphere and viewing of the sky in the range of 10-3000 keV and track gamma-ray spectrometer of high resolution and sensitivity. The detector assembly of each BDG block is made in the form of an assembly of a thin (0.3 cm) NaI (Tl) scintillator and a CsI (Tl) scintillator of a larger cylindrical shape (1.7 cm). Both scintillation crystals have the same diameter of 13 cm and can be viewed with a single photomultiplier - the so-called “fosvich”. The axes of the three gamma detectors of the BDGG type are perpendicular to each other and directed along mutually perpendicular edges of the cube, as if forming a Cartesian coordinate system. In this case, the main diagonal of the cube is oriented to nadir.

A high resolution and sensitivity gamma-ray spectrometer is a combination of a position-sensitive detector with an encoding mask. The device also includes a hodoscopic unit based on scintillation fibers. The axis of the device should be oriented along the axis of "nadir - zenith", while from the side of the coding mask, the device should be oriented to zenith, and from the hodoscopic node to nadir. The effective area of the gamma spectrometer is ~ 250 cm2, the energy range is 50-5000 keV (in the encoding mode 50-1000 keV), the angular resolution is ~ 2 °, the field of view of the full encoding is ± 25 ° degrees. The gamma telescope makes it possible to check the appearance of a point source and, thus, to separate gamma-ray bursts of various nature from rashes of particles. The equipment also includes a data analysis unit containing digital electronics nodes that allow recording readings with a high temporal resolution (up to 10 μs), performing operational analysis of images from a telescope with a coding mask, and also generating a gamma-ray burst trigger.

Ground control complex

In the course of the space experiment, a ground-based complex can be used (Lomonosov Satellite: the first research results Sadovnichy VA, Panasyuk MI, Makridenko LA in the journal Earth and the Universe, No. 2, pp. 3-16 )

Along with the system for receiving and processing space scientific telemetry, a system for operational analysis and forecasting of radiation conditions in the OKP created at Moscow State University can be used, based on an automated analysis of space monitoring data using operational models of external environmental factors [Kalegaev VV, Bobrovnikov S .Yu., Kuznetsov N.V., Myagkova I.N., Shugai Yu.S. Center for Operational Space Monitoring, SINP MSU // Applied aspects of heliogeo-physics. Materials of the special section "Practical Aspects of Space Weather Science" of the 11th annual conference "Plasma Physics in the Solar System". M .: IKI RAS. 2016. S. 146-159].

Thus, the satellite constellation implementing the claimed method allows us to solve the following technical problems:

- operative (in real time) assessment of radiation conditions in near-Earth space to assess radiation risks of space missions and generate alert signals for decision-making on their management;

- verification of modern calculation models of radiation fields of near-Earth space;

- operational control of potentially dangerous objects of natural and technogenic origin in near-Earth space;

- control of electromagnetic transients in the upper atmosphere of the Earth and outer space (gamma-ray bursts, solar flares).

The proposed method allows you to:

- create a space system for monitoring and preventing space threats for both ongoing and planned space missions, including high-altitude atmospheric aircraft;

- to provide an increase in the amount of information received, while at the same time sharply reducing its cost.

The claimed orbital constellation of satellites differing in the spatial position of the orbital plane and the true anomaly of the satellite in orbit.

Claims (11)

1. A method of forming a constellation of artificial Earth satellites (AES) for monitoring potentially dangerous threats in near-Earth space equipped with spectrometric equipment, including placing at least three AES in different orbits crossing the L-shells of the Earth’s radiation belts at different points at different altitudes, characterized in that at least two circular orbits are used: a low solar-synchronous orbit with a height of 500-650 km and an inclination of 97-98 ° and an orbit close to a circular one with an altitude of 1400-1500 km and an inclination ~ 80 °, as well as at least one elliptical orbit with an apogee of 8000 km, a perigee of 600-700 km and an inclination of ~ 63.4 °, while the orbits are selected so that the perigee argument of the orbit is less than 3-4 degrees. /year. 2. The method according to p. 1, characterized in that when placing more than one satellite in one orbit, form an orbital structure with a uniform distribution of the satellite in orbit. 3. The method according to p. 1, characterized in that as spectrometric equipment for monitoring the radiation situation using spectrometers of particles and radiation, including a spectrometer of energetic protons and electrons, containing several semiconductor telescopes with different spatial orientations of their axes, and the axes of all telescopes except one, in the measurement mode, they are oriented in the plane of the magnetic meridian, and the indicated one telescope is perpendicular to this plane. 4. The method according to p. 1, characterized in that the spectrometric equipment for monitoring the radiation situation is installed on all satellites of the satellite constellation, while the satellites placed in circular orbits additionally place equipment for monitoring electromagnetic transients - space and atmospheric gamma-ray bursts and bursts of optical and ultraviolet radiation from the Earth’s atmosphere. 5. The method according to p. 3, characterized in that the spectrometric equipment for monitoring the radiation environment includes a proton spectrometer in the energy range from 1 to> 160 MeV and electrons in the energy range from 0.15 to 10 MeV. 6. The method according to p. 1, characterized in that the spectrometric equipment for monitoring the radiation situation includes a 3-component magnetometer with the ability to measure magnetic field variations at frequencies up to 100 Hz. 7. The method according to p. 4, characterized in that as a spectrometric apparatus for monitoring electromagnetic transients use three broadly directed scintillation fosvich detectors of gamma radiation in the range of 10-3000 keV, the axes of which are located in mutually perpendicular directions, and a track gamma spectrometer with a recorded energy range of at least 50-5000 keV, an angular resolution of at least ~ 6 °, and a field of view of at least ± 25 ° degrees. 8. The method according to p. 7, characterized in that the main axis of the block of detectors and track gamma-ray spectrometer is oriented to nadir. 9. The method according to p. 4, characterized in that as a spectrometric apparatus for monitoring electromagnetic transients use a spatially sensitive spectrometer with detectors of UV and IR radiation directed to nadir. 10. A method for monitoring potentially dangerous threats in near-Earth space, including the formation of a satellite constellation according to claim 1, with the duty cycle of transmitting information to the Earth, preferably at least 0.5-4 hours depending on the orbit, transmitting and processing the measured data in the ground center processing. 11. The method according to p. 10, characterized in that the spectrometric equipment placed on different satellites is synchronized with reference to the unified world time with an accuracy of at least 3-5 μs.

Images