An imminent discovery near-earth asteroid alert system

Abstract

The application discloses a near-earth asteroid warning system based on imminent discovery, and belongs to the field of near-earth asteroid monitoring and early warning. The application is realized based on space-based equipment, and comprises a fence type space guard orbit and patrol strategy module, a space telescope satisfying the requirements of a large field of view and high sensitivity, and a segmented satellite platform. The fence type space guard orbit and patrol strategy module has stable space guard and rapid and efficient patrol capabilities, and a space-based system is arranged on a relative sun-earth stable orbit for the guard of near-earth asteroids. The space telescope has daily patrol detection and accurate size detection capabilities, adopts a space telescope with a large field of view and high sensitivity, has a detection and discovery capability of 50-meter-level asteroids at a distance of 10 million kilometers, and adopts a visible light and infrared integrated detection system. The segmented satellite platform satisfies the requirements of the satellite overall for orbit entry and extended orbit transfer tests, load deep low-temperature work and efficient and stable attitude maneuvering patrol strategies.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of near-Earth asteroid monitoring and early warning, and relates to a system for early warning of near-Earth asteroids by constructing a "spherical shell type" monitoring fence around the Earth through a space-based monitoring device. BACKGROUND

[0002] Early discovery and early warning of asteroids is a prerequisite for preventing and resolving the risk of near-Earth asteroid impact, so it is particularly important to carry out monitoring and early warning of near-Earth asteroids. Due to the complex target characteristics of near-Earth asteroids, in addition to the need for wide-area patrol monitoring to discover and catalog asteroids at a relatively long distance, it is also necessary to discover and early warn uncataloged asteroids at a relatively short distance, so as to achieve comprehensive monitoring and early warning of near-Earth asteroids. Through special ground-based optical telescopes, radar systems, and multiple optical, infrared, and spectral devices, countries such as the United States and Europe have basically completed the cataloging and early warning of kilometer-level near-Earth asteroids, but the cataloging rate of asteroids with a diameter of 50 meters or less is less than 10%, and it is impossible to achieve comprehensive cataloging and early warning in the short term. At present, China only has one ground-based 1.2-meter diameter special optical monitoring telescope at the Purple Mountain Observatory of the Chinese Academy of Sciences, and there are problems such as insufficient number of devices, limited layout, and insufficient monitoring capacity.

[0003] In order to fill the gap in space-based monitoring and early warning of near-Earth asteroids in China, and to enrich and improve monitoring means and explore new warning modes, this patent breaks the traditional idea of relying on comprehensive cataloging information to achieve "cataloging and early warning" of near-Earth asteroids, selects a relatively stable orbit around the sun and the Earth to deploy a space-based system, considers accurate orbit determination and measurement of physical and chemical properties, designs and configures a multi-spectral large field-of-view high-sensitivity telescope to improve the observation capability of the telescope, and constructs a "spherical shell type" fence warning system around the Earth 10 million to 18.64 million kilometers away, which can achieve discovery and early warning of unknown near-Earth asteroids passing through the fence, and provide support for the development and construction of China's space-based monitoring and early warning capability system.

[0004] Humanity has cataloged less than 10% of near-Earth asteroids with a diameter of 50 meters or less, and it is impossible to achieve comprehensive cataloging and early warning in the short term, especially in the monitoring of near-Earth asteroids, there are problems such as insufficient number of devices, limited layout, and insufficient monitoring capacity. SUMMARY

[0005] Unlike the need to rely on comprehensive catalog information to achieve near-earth asteroid "catalog early warning" idea, in order to overcome the deficiency that near-earth asteroid cannot be fully cataloged and warned in a short period of time, the main purpose of the present application is to provide a discovery and warning type of threatening near-earth asteroid warning system, to build a "spherical shell type" monitoring fence around the earth, to realize the imminent warning of near-earth asteroids passing through the fence, and to complement the catalog monitoring information and improve the size attribute measurement information of near-earth asteroids, and to realize the imminent discovery type warning of threatening near-earth asteroids (such as PHA) based on space-based equipment.

[0006] The purpose of the present application is realized by the following technical solutions.

[0007] The imminent discovery type near-earth asteroid warning system disclosed by the present application is realized based on space-based equipment, and comprises a fence type space guard orbit and patrol strategy module, a space telescope meeting the requirements of large field of view and high sensitivity, and a segmented satellite platform.

[0008] The fence type space guard orbit and patrol strategy module has stable space guard and rapid and efficient patrol capabilities, and is used for the guard of near-earth asteroids by deploying space-based systems in a relative sun-earth stable orbit, a "spherical shell type" fence warning module is constructed in a spherical observation region in space, which is around the earth 1000-1864 million kilometers, the guard sky of the space-based system is expanded, and the rapid and efficient patrol scanning strategy is matched, so that the discovery and warning of imminent asteroids for at least 5 days are realized.

[0009] The space telescope meeting the requirements of large field of view and high sensitivity has the capabilities of daily patrol detection and accurate size detection, adopts a space telescope with a large field of view of 9 square degrees and high sensitivity of 22 limit star magnitudes, realizes the detection and discovery capability of 50 meter level asteroids at a distance of 1000 million kilometers, and adopts a visible light and infrared integrated detection system to meet the requirements of accurate orbit and size measurement of asteroids.

[0010] The segmented satellite platform which can be implemented in engineering inherits the AP-6E, CE-2 and CE-4 engineering baseline, meets the requirements of satellite overall for orbit transfer test and extended orbit transfer test, load deep low temperature work and efficient and stable attitude maneuvering patrol strategy.

[0011] Through the cooperation of the fence type space guard orbit and patrol strategy module, the space telescope and the segmented satellite platform, the requirements of integrated test in multiple scenes such as warning, cataloging and attribute detection are met synchronously, the requirements of accurate attribute detection of asteroids are met, and the system has good engineering inheritance and feasibility, so that the discovery and warning of unknown near-earth asteroids passing through the "spherical shell type" fence are realized.

[0012] As preferred, the visible sky area of the space telescope is divided, each unit is scanned in turn, and the whole visible sky area is scanned.

[0013] As further preferred, the field of view of the space telescope is 9 square degrees, and an integrated visible light and infrared detection system is used, and the NEATM (Near-Earth Asteroid Thermal Model) is used to consider the spin and thermal inertia distribution of the asteroid, and the dual infrared spectrum of 5 and 8 microns is selected to carry out high-precision size inversion and search and discovery of the target; the 0.6-micron visible light spectrum is used to carry out efficient patrol search, and under the support of the simultaneously acquired brightness data with the same phase and accuracy, the overall size measurement accuracy is within ± 15%, and high-precision size detection of the target asteroid is realized.

[0014] As preferred, the segmented satellite platform adopts multi-stage passive thermal insulation combined with active low-temperature refrigeration, is composed of a platform service cabin and a light shield, and adopts thermal insulation and vibration isolation design between the platform loads, effectively meeting the passive deep low-temperature working temperature range and high attitude stability control requirements of the integrated visible light and infrared telescope.

[0015] Advantages:

[0016] 1. The imminent discovery type near-Earth asteroid warning system disclosed by the application has a relatively stable orbit position relative to the sun and the earth, and the designed "spherical shell type" fence warning system can independently realize the discovery and warning of the imminent asteroid by combining the observation field of view and the scanning strategy and approximately wrapping the whole earth (the spherical degree of the observation area is 29170 square degrees, about 7 / 2pi sky area).

[0017] 2. The imminent discovery type near-Earth asteroid warning system can realize efficient cataloging of unknown asteroids. Based on the main task of warning, through data processing or switching of the sky survey strategy, the key observation area can be expanded from the "spherical shell type" fence warning area to the entire spherical observation area under the limit observation distance. After simulation calculation, it is expected that 2 / 3 of the 140-meter-level asteroid discovery cataloging can be completed in 5 years, the index is comparable to the NEO Surveyor space-based infrared task implemented by the United States, and the sky survey cataloging and warning task can be realized.

[0018] 3. The imminent discovery type near-Earth asteroid warning system can meet the accurate attribute detection requirements of asteroids. Diameter and other parameters are the core indicators for quantitatively evaluating the impact risk. The size measurement error of the single visible light system is large due to the influence of albedo, and cannot meet the accurate measurement requirements. The infrared system can directly determine the information according to the radiation brightness, and the size accuracy can reach within ± 30%. Further, through the visible light and infrared integrated detection system, under the support of simultaneously acquiring the brightness data of the observed target at the same phase and accuracy, the size measurement accuracy can reach within ± 15%, and the high-precision size detection of the target asteroid can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Space-based system space value guard schematic diagram of near-Earth asteroid at L1 point of Sun-Earth;

[0020] Figure 2 System working mode schematic diagram in near-Earth asteroid imminent process;

[0021] Figure 3 Sky survey strategy schematic diagram of the warning system;

[0022] Figure 4 Space telescope design schematic diagram;

[0023] Figure 5 Segmented satellite platform design schematic diagram. DETAILED DESCRIPTION

[0024] In order to better illustrate the purpose and advantages of the present application, the content of the application will be further described below in combination with the drawings and examples.

[0025] The "spherical shell type" fence warning system design scheme of the near-Earth asteroid imminent discovery type based on space-based equipment, which is composed of (1) a fence type space value guard orbit and sky survey strategy scheme, (2) a space telescope meeting the requirements of large field of view and high sensitivity, and (3) an engineering inherited segmented satellite platform, can meet the requirements of warning, cataloging, attribute detection and other scene test integrated design, meet the accurate attribute detection requirements of asteroids, have good engineering inheritance and realization, and can realize the discovery and warning of unknown near-Earth asteroids passing through the "spherical shell type" fence.

[0026] like Figure 1 The diagram shows a space-based monitoring illustration of the near-Earth asteroid space-based system at the Sun-Earth L1 point. The Sun-Earth Lagrange L1 point is located at a distance of 150 × 10⁻⁶ meters from Earth along the line connecting the Sun and Earth. 4 At kilometer marker L1, the Sun-Earth gravitational translation point is located. Deploying a space-based telescope at the Sun-Earth L1 point offers advantages such as a relatively fixed relative position between the telescope, Earth, and the Sun, good engineering feasibility, and low launch-to-orbit energy, making it one of the ideal observation sites for near-Earth asteroid monitoring and early warning missions. This system is designed with the telescope deployed in a halo orbit around the Sun-Earth L1 point to conduct routine sky surveys, cataloging, and threat warnings. Considering factors such as solar avoidance, the telescope's instantaneous observation field of view is centered along Earth's orbit, pointing to both sides. Calculations show that at magnitude 22, the telescope's maximum observation distance is approximately 53.57 million kilometers (equivalent to a 140-meter asteroid at 1 AU) for a 50-meter-class asteroid. The final observation field of view will form a spherical observable sky region with a radius of 53.57 million kilometers, resembling a circle around the Earth. Furthermore, the system can complement the ground-based system by dividing the observation area into two complementary roles: the ground-based system primarily handles the area facing away from the Sun, while the space-based system primarily handles the dominant monitoring area on the Sun's side, achieving continuous detection and warning through coordinated space-ground cooperation.

[0027] like Figure 2 The diagram shows the system's operating modes during an asteroid approach. Dividing the system by the asteroid's approach distance to Earth, the monitoring and early warning system primarily sets up three mission scenarios: daily cataloging, threat warning, and short-term forecasting. For the threat warning mission scenario, to fully utilize its effectiveness and expand the manageable area of ​​the space-based monitoring system, a "spherical shell" warning fence is designed around Earth within the space observation sphere. (The inner boundary of the fence is set at 10 million kilometers; based on the asteroid's relative speed of 20 km / s, the asteroid's travel distance is calculated to be 8.64 million kilometers with a 5-day warning period, resulting in an outer boundary of 18.64 million kilometers). This ensures that the Sun-Earth L1 point space-based observation system can detect approaching asteroids within the "spherical shell" fence area at least 5 days in advance, thus achieving warnings from 10 million kilometers away.

[0028] like Figure 3The diagram shows the sky-scanning strategy of the alarm system. Each instantaneous observation field of view is a basic unit of observation scanning. By setting the observation time and scanning direction, the scanning strategy can be determined. The design of the space-based telescope's instantaneous observation field of view is as follows: the center of the field of view points to both sides along the Earth's orbit (ecliptic latitude 0°~360°, ecliptic longitude 45°~135°), with a field of view of 9 square degrees (3°×3°) and a dwell time of 60s (40s observation integration time, 20s attitude adjustment). Based on this, the telescope's visible sky area is divided, and the design scans each unit sequentially according to the diagram to achieve scanning of the entire visible sky area. Simultaneously, the telescope can also change the scanning method to allow the space-based observation area and the ground-based system to complement each other within the visible sky area. The ground-based system mainly handles the sky area facing away from the sun, while the space-based system mainly handles the dominant monitoring area on the sun's side, achieving continuous detection and alarm through coordinated space-ground cooperation.

[0029] like Figure 4 The diagram shows a schematic of the space telescope design. The system is designed with a telescope field of view of 9 square degrees, and its maximum detection capability at magnitude 22 is approximately 53.57 million kilometers from a 50-meter-class asteroid. It employs an integrated visible and infrared detection system, comprehensively considering factors such as asteroid spin and thermal inertia distribution. A comprehensive and applicable near-Earth asteroid thermal model (NEATM) is used, selecting dual infrared bands of 5μm and 8μm for high-precision target size inversion and search discovery; the 0.6μm visible spectrum band is used for efficient sky surveys. Ultimately, with the support of brightness data acquired simultaneously, in phase, and with the same precision, the overall size measurement accuracy can reach within ±15%, achieving high-precision size detection of the target asteroid.

[0030] like Figure 5 The diagram shows a design schematic of a segmented satellite platform. The Sun-Earth L1 orbit space-based observation system, equipped with a visible-infrared integrated telescope, not only places higher demands on the energy and temperature control of the observation payloads, but also has a strong need for long-term operation and multi-orbital-position experiments. The segmented satellite platform design, employing a monitoring and early warning satellite platform and a separable propulsion module, can inherit mature engineering implementation experience from previous projects, meeting the requirements for payload insertion into orbit and survey strategies while improving the feasibility of the project. The monitoring and early warning satellite platform adopts a multi-stage passive thermal insulation combined with active cryogenic cooling design, consisting of a platform service module and a sunshade. Simultaneously, thermal insulation and vibration isolation designs are used between the platform payloads, effectively meeting the requirements of the visible-infrared integrated telescope for passive deep cryogenic operating temperature range and high attitude stability control. The separable propulsion module is a modification of the AP-6E, separating after reaching the Sun-Earth L1 point, effectively saving energy consumption required for long-term on-orbit experiments, operational use, and multi-orbital-position experimental mission expansion.

[0031] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A near-Earth asteroid warning system based on proximity detection, characterized in that: Based primarily on space-based equipment, including a fence-like space-guarded orbital position and sky-scanning strategy module, a space telescope that meets the requirements of a large field of view and high sensitivity, and a segmented satellite platform; The aforementioned fence-like space-based monitoring orbit and survey strategy module has stable space monitoring and rapid and efficient survey capabilities. It deploys a space-based system in a relatively stable Sun-Earth orbit for monitoring near-Earth asteroids. Within the spherical observation area, it constructs a "spherical shell" alarm module surrounding the Earth at a distance of 10 million to 18.64 million kilometers, expanding the monitoring area of ​​the space-based system. Combined with a rapid and efficient survey scanning strategy, it enables the detection and alarm of approaching asteroids for at least 5 days. The space telescope described above meets the requirements of a large field of view and high sensitivity, taking into account both routine sky survey and precise size detection capabilities. It adopts a space telescope with a 9 square degree large field of view and a 22 limiting magnitude high sensitivity, enabling it to detect and discover 50-meter-class asteroids at a distance of 10 million kilometers. At the same time, it adopts an integrated visible light and infrared detection system to meet the needs of precise asteroid orbit determination and size measurement. The segmented satellite platform fully inherits the engineering baselines of AP-6E, CE-2, and CE-4, and meets the overall requirements of the satellite for orbit insertion and extended orbit transfer tests, deep cryogenic operation of payloads, and efficient and stable attitude maneuvering survey strategies.

2. The near-Earth asteroid warning system based on proximity detection as described in claim 1, characterized in that: By achieving the coordinated operation of the fence-like space-guarded orbital position and sky-scanning strategy module, space telescope, and segmented satellite platform, the system simultaneously meets the integrated requirements of multiple scenarios for alarm, cataloging, and attribute detection, fulfilling the need for precise asteroid attribute detection and enabling the discovery and alarm of unknown near-Earth asteroids approaching and crossing the "spherical" fence.

3. A near-Earth asteroid warning system based on proximity detection as described in claim 1 or 2, characterized in that: The visible sky area of ​​the space telescope is divided into sections, and each section is scanned sequentially to achieve a full scan of the visible sky area. At the same time, the telescope also changes its scanning method to allow the space-based observation and monitoring area and the ground-based system to cooperate and complement each other within the visible sky area. The ground-based system is mainly responsible for the sky area facing away from the sun, while the space-based system is mainly responsible for the dominant monitoring area on the side of the sun, so as to achieve uninterrupted detection and alarm through coordinated efforts between space and ground.

4. The near-Earth asteroid warning system based on proximity detection as described in claim 3, characterized in that: The space telescope has a field of view of 9 square degrees and adopts an integrated visible and infrared detection system. Taking into account the asteroid's spin and thermal inertia distribution, it uses the NEATM thermal model for near-Earth asteroids, which takes into account both applications. It selects the 5μm and 8μm dual infrared bands to carry out high-precision size inversion and search and discovery of the target. It uses the 0.6μm visible spectrum band to carry out efficient sky survey search. With the support of brightness data acquired simultaneously, in the same phase and with the same precision, the overall size measurement accuracy is within ±15%, realizing high-precision size detection of the target asteroid.

5. A near-Earth asteroid warning system based on proximity detection as described in claim 1 or 2, characterized in that: The segmented satellite platform adopts a multi-level passive thermal insulation combined with active cryogenic cooling, and consists of a platform service module and a sunshade. At the same time, the platform payloads adopt thermal insulation and vibration isolation design, which effectively meets the requirements of the visible light and infrared integrated telescope for passive deep cryogenic operating temperature range and high attitude stability control. The separation propulsion module is a modification of the AP-6E. After reaching the Sun-Earth L1 point, it separates, effectively saving energy consumption required for long-term on-orbit testing, operational use, and expansion of multi-orbit test missions.

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