Radiation shielding system, flying body, and radiation shielding method

Abstract

A radiation shielding system (100) for shielding a spacecraft (1) from incoming radiation comprises: a flying body (2); and a control device (31) mounted on the spacecraft (1). The flying body (2) includes a propulsion engine (23), a drive control unit (22) for controlling the driving of the propulsion engine (23), and a shielding material (24) for shielding the spacecraft (1) from radiation. The control device (31) includes: a position setting unit (11) that sets, between the spacecraft (1) and the Sun (Q1), a position separated by a prescribed distance from the spacecraft (1) as a stop position of the flying body (2); and a control command unit (12) that outputs a control command to the drive control unit (22) so that the flying body (2) stays at the stop position.

Description

Radiation shielding system, aircraft, and radiation shielding method

[0001] The present disclosure relates to a radiation shielding system, an air vehicle, and a radiation shielding method.

[0002] Spacecraft flying in outer space, such as space stations and artificial satellites, are exposed to cosmic radiation caused by solar flares, etc. Techniques disclosed in Non-Patent Documents 1 and 2 have been proposed as methods for protecting the human body, electronic devices, etc. from cosmic radiation.

[0003] Non-Patent Document 1 discloses a method of shielding a spacecraft from cosmic radiation by installing a physical barrier on the outer wall of the spacecraft. Non-Patent Document 2 discloses a method of avoiding cosmic radiation exposure to a spacecraft by installing a magnetic barrier on the outer wall of the spacecraft to shift the trajectory of the cosmic radiation.

[0004] "Physical Barrier" https: / / ieeexplore.ieee.org / document / 8003007 "Magnetic Field Barrier" https: / / ieeexplore.ieee.org / document / 7792167

[0005] However, although the method of installing a physical barrier can block cosmic radiation to a certain extent, the nuclear reaction between the cosmic radiation and the shielding material that forms the physical barrier generates neutrons with high penetrating power. In order to block these neutrons, a thicker shielding material must be used, which results in problems such as an increase in the size and cost of the device.

[0006] In addition, space radiation has very high kinetic energy, making it difficult to significantly change its trajectory by applying a magnetic field to it. Therefore, it is difficult to protect spacecraft from space radiation even by installing a magnetic barrier. Furthermore, generating a strong magnetic field could adversely affect activities outside the spacecraft.

[0007] The present disclosure has been made in consideration of the above circumstances, and its purpose is to provide a radiation shielding system, an aircraft, and a radiation shielding method that can shield a spacecraft from cosmic radiation irradiated thereto in a simple manner.

[0008] A radiation shielding system according to one aspect of the present disclosure is a radiation shielding system that shields a spacecraft from radiation entering the spacecraft, and comprises an aircraft and a control device mounted on the spacecraft, wherein the aircraft comprises a flight drive source, a drive control unit that controls the drive of the flight drive source, and a shield that blocks radiation, and the control device comprises a position setting unit that sets a position between the spacecraft and the sun, a predetermined distance away from the spacecraft, as a parking position for the aircraft, and a control command unit that outputs a control command to the drive control unit so that the aircraft stays at the parking position.

[0009] One aspect of the flying body of the present disclosure is a flying body that shields a spacecraft from radiation that is coming toward the spacecraft, and includes a flight drive source, a shield that shields the radiation, and a drive control unit that controls the drive of the flight drive source so that the shield remains stationary at a position a predetermined distance from the spacecraft between the spacecraft and the sun.

[0010] A radiation shielding method according to one aspect of the present disclosure is a radiation shielding method for shielding radiation coming toward a spacecraft, in which a position setting unit sets a position between the spacecraft and the sun, a predetermined distance away from the spacecraft, as a position for stopping the aircraft, and a control command unit outputs a control command to a drive control unit so that the aircraft stops at the position set by the position setting unit.

[0011] According to the present disclosure, it is possible to shield a spacecraft from cosmic radiation irradiated thereto in a simple manner.

[0012] FIG. 1 is a block diagram showing the configuration of a radiation shielding system according to a first embodiment. FIG. 2 is an explanatory diagram according to the first embodiment, which schematically shows a state in which a flying object is launched from a spacecraft. FIG. 3 is an explanatory diagram according to the first embodiment, which shows a state in which a shielding material is installed between the spacecraft and the sun to block cosmic radiation. FIG. 4 is a block diagram showing the configuration of a radiation shielding system according to a second embodiment. FIG. 5 is an explanatory diagram according to the second embodiment, which schematically shows a state in which a flying object is launched from a spacecraft. FIG. 6 is an explanatory diagram according to the second embodiment, which shows a state in which a magnetic field barrier is installed between the spacecraft and the sun to block cosmic radiation. FIG. 7 is a block diagram showing the hardware configuration of this embodiment.

[0013] [Description of First Embodiment] Hereinafter, an embodiment will be described with reference to the drawings. Fig. 1 is a block diagram showing the configuration of a radiation shielding system 100 according to a first embodiment. Fig. 2 is an explanatory diagram showing a schematic view of a flying object 2 being launched from a spacecraft 1 such as a space station or an artificial satellite. Fig. 3 is an explanatory diagram showing a view of shielding from cosmic radiation s1 by installing a shielding material 24 between the spacecraft 1 and the sun Q1.

[0014] As shown in Figure 2, the radiation shielding system 100 according to this embodiment launches a flying object 2 installed on a spacecraft 1 toward the sun Q1. For example, the flying object 2 is flown to a position several hundred meters away from the spacecraft 1, and by stopping the flying object 2 at this position, a shielding material 24 is placed between the spacecraft 1 and the sun Q1. By placing the shielding material 24, cosmic radiation arriving at the spacecraft 1 is shielded. When cosmic radiation collides with the shielding material 24, neutrons are emitted in random directions. By setting a large distance between the shielding material 24 and the spacecraft 1, the number of neutrons arriving at the spacecraft 1 is reduced.

[0015] As shown in FIG. 1 , the radiation shielding system 100 according to the first embodiment includes a control device 31 installed in a spacecraft 1 and an aircraft 2 .

[0016] The control device 31 includes a position setting unit 11 , a control command unit 12 , and a communication unit 13 .

[0017] The position setting unit 11 sets the parking position of the aircraft 2. The parking position of the aircraft 2 is set to a position between the spacecraft 1 and the sun Q1, a predetermined distance away from the spacecraft 1. The predetermined distance is, for example, several hundred meters (100 meters or more).

[0018] The control command unit 12 outputs a control command to move the flying object 2 to the parking position set by the position setting unit 11 .

[0019] The communication unit 13 communicates with the flying object 2. The communication unit 13 transmits the control command output from the control command unit 12 to the flying object 2. The communication unit 13 receives current position information of the flying object 2 transmitted from the flying object 2, and outputs it to the position setting unit 11.

[0020] The flying object 2 includes a communication unit 21, a drive control unit 22, a propulsion engine 23 (flight drive source), and a shielding material 24. The shielding material 24 is an example of a shield that blocks radiation.

[0021] The communication unit 21 communicates with a control device 31 installed in the spacecraft 1 .

[0022] The drive control unit 22 controls the operation of the propulsion engine 23. The drive control unit 22 controls the propulsion engine 23 so that the flying body 2 moves to and stops at a flight position set by the control device 31 of the spacecraft 1.

[0023] The propulsion engine 23 launches the flying vehicle 2 from the spacecraft 1 and causes it to fly when a flight command for the flying vehicle 2 is input to the control device 31. Under the control of the drive control unit 22, the propulsion engine 23 can move the flying vehicle 2 in any direction and for any distance within 360° around the spacecraft 1 and stop it at the moved position. Note that, in this embodiment, an example will be described in which the propulsion engine 23 is used as a flight drive source for flying the flying vehicle 2, but other flight drive sources such as a motor may also be used.

[0024] The propulsion engine 23, under the control of the drive control unit 22, flies the aircraft 2 so that it stays between the spacecraft 1 and the sun Q1, for example, at a position several hundred meters away from the spacecraft 1. Even if the relative positions of the spacecraft 1 and the sun Q1 change, the drive control unit 22 controls the propulsion engine 23 to move the aircraft 2 in accordance with this change in relative position so that the aircraft 2 stays between the spacecraft 1 and the sun Q1.

[0025] The shielding material 24 has a planar shape with sides of, for example, several meters to several tens of meters. The shielding material 24 may be made of a material that has a radiation shielding function, such as tantalum, tungsten, lead, or aluminum. That is, the shielding material 24 containing at least one of tantalum, tungsten, lead, and aluminum can be used as a shielding body.

[0026] In addition to being launched from the spacecraft 1, the flying object 2 may also be launched from the ground, for example, and flown to a desired position around the spacecraft 1.

[0027] Next, the operation of the radiation shielding system 100 according to the first embodiment will be described. When a launch command for the flying vehicle 2 is input to the control device 31 by a user stationed on the spacecraft 1 or by remote operation, this launch command is transmitted from the communication unit 13 to the flying vehicle 2. This launch command is received by the communication unit 21 and output to the drive control unit 22. The drive control unit 22 controls the propulsion engine 23 to fly the flying vehicle 2 in space.

[0028] The position setting unit 11 of the control device 31 sets the parking position of the flying object 2 based on the current position of the spacecraft 1 and the direction of the sun Q1.

[0029] The control command unit 12 acquires the current position information of the flying object 2, and outputs a control command to move the flying object 2 to the stopping position set by the position setting unit 11 based on the current position coordinates and the information on the stopping position of the flying object 2. This control command is transmitted from the communication unit 13 to the communication unit 21 of the flying object 2.

[0030] The drive control unit 22 of the aircraft 2 controls the propulsion engine 23 so that the shielding material 24 stays at the stopping position set by the position setting unit 11. Specifically, the propulsion engine 23 is controlled so that the shielding material 24 stays at a position between the spacecraft 1 and the sun Q1, a predetermined distance (e.g., several hundred meters) away from the spacecraft 1. That is, among cosmic radiation, cosmic radiation generated due to solar flares comes from the direction of the sun Q1 in places where there is no influence of geomagnetism, etc. Therefore, it is preferable to install the shielding material 24 between the spacecraft 1 and the sun Q1.

[0031] As a result, the shielding material 24 is positioned between the spacecraft 1 and the sun Q1, as shown in Figure 3. Furthermore, if the relative positional relationship between the spacecraft 1 and the sun Q1 changes, the position of the flying body 2 is adjusted to follow this change.

[0032] When cosmic radiation caused by solar flares or the like collides with the shielding material 24, the collision generates neutrons oriented in random directions. The number of neutrons reaching the spacecraft 1 decreases in inverse proportion to the square of the distance between the spacecraft 1 and the shielding material 24. In this embodiment, the distance between the spacecraft 1 and the shielding material 24 is set to several hundred meters. Therefore, the number of neutrons reaching the spacecraft 1 is dramatically reduced compared to when the shielding material 24 is installed close to the spacecraft 1 (for example, at a distance of about 1 meter).

[0033] For example, when the shielding material 24 is installed at a distance of 1 m from the spacecraft 1 and at a distance of 100 m, the radiation intensity is reduced to about 1 / 10,000 of that when the shielding material 24 is installed at a distance of 1 m. Therefore, it is possible to protect the spacecraft 1 from cosmic radiation.

[0034] As described above, this embodiment is a radiation shielding system 100 that shields the spacecraft 1 from radiation (cosmic radiation), and includes an aircraft 2 and a control device 31 mounted on the spacecraft 1. The aircraft 2 includes a propulsion engine 23 (flight drive source), a drive control unit 22 that controls the drive of the propulsion engine 23, and a shielding material 24 (shielding body) that shields against radiation. The control device 31 includes a position setting unit 11 that sets a position a predetermined distance away from the spacecraft 1 between the spacecraft 1 and the sun Q1 as the parking position of the aircraft 2, and a control command unit 12 that outputs a control command to the drive control unit 22 so that the aircraft 2 parks at the parking position.

[0035] In this embodiment, the flying object 2 equipped with the shielding material 24 is flown, and the shielding material 24 is parked at a distance of about several hundred meters between the spacecraft 1 and the sun Q1. As a result, the number of neutrons that are generated when cosmic radiation collides with the shielding material 24 and that reach the spacecraft 1 can be reduced, and the spacecraft 1 can be protected from cosmic radiation. In addition, the effects on the human body, electronic devices, etc. can be reduced.

[0036] Furthermore, even if the relative position between the spacecraft 1 and the sun Q1 changes, the position of the flying body 2 is adjusted to follow this change, thereby making it possible to stably shield the spacecraft 1 from cosmic radiation.

[0037] [Description of Second Embodiment] Next, a second embodiment will be described. Fig. 4 is a block diagram showing the configuration of a radiation shielding system 101 according to the second embodiment. Fig. 5 is an explanatory diagram showing a schematic view of a flying object 2A being launched from a spacecraft 1 such as a space station or an artificial satellite. Fig. 6 is an explanatory diagram showing a view of a magnetic field barrier 25 being installed between the spacecraft 1 and the sun Q1 to change the trajectory of cosmic radiation s1.

[0038] 5, the radiation shielding system 101 according to the second embodiment launches a flying object 2A installed in a spacecraft 1 toward the sun Q1. For example, the flying object 2A is flown to a position several hundred meters away from the spacecraft 1, and by having the flying object 2 stop at this position, a magnetic field barrier 25 is placed between the spacecraft 1 and the sun Q1. By placing the magnetic field barrier 25, the trajectory (direction of emission) of cosmic radiation arriving at the spacecraft 1 is changed, thereby reducing the amount of cosmic radiation reaching the spacecraft 1.

[0039] As shown in FIG. 4, the radiation shielding system 101 according to the second embodiment includes a control device 32 installed in the spacecraft 1 and an aircraft 2A.

[0040] The control device 32 includes a position setting unit 11, a control command unit 12, and a communication unit 13. These components are the same as those in Fig. 1, and therefore the same reference numerals are used and a description of the configuration will be omitted.

[0041] The flying vehicle 2A includes a communication unit 21, a drive control unit 22, a propulsion engine 23 (flight drive source), and a magnetic field barrier 25. The communication unit 21, drive control unit 22, and propulsion engine 23 are the same as those shown in Fig. 1 above, and therefore the same reference numerals are used and a description of their configurations will be omitted.

[0042] The magnetic field barrier 25 has a planar shape with sides of, for example, several meters to several hundred meters, and generates a magnetic field around it. By generating a magnetic field around it, the trajectory of cosmic radiation that collides with the magnetic field barrier 25 or passes near the magnetic field barrier 25 can be changed, thereby reducing the number of cosmic radiation particles that reach the spacecraft 1 and protecting the spacecraft 1. A permanent magnet, an electromagnet, or a superconducting magnet can be used as the magnetic field barrier 25. The magnetic field barrier 25 is an example of a shield that blocks cosmic radiation.

[0043] In addition to being launched from the spacecraft 1, the flying object 2 may also be launched from the ground, for example, and flown to a desired position around the spacecraft 1.

[0044] Next, the operation of the radiation shielding system 101 according to the second embodiment will be described. When a launch command for the flying vehicle 2A is input to the control device 32 by a user stationed on the spacecraft 1 or by remote operation, this launch command is transmitted to the flying vehicle 2A from the communication unit 13. This launch command is received by the communication unit 21 and output to the drive control unit 22. The drive control unit 22 controls the propulsion engine 23 to fly the flying vehicle 2A in space.

[0045] The position setting unit 11 of the control device 32 sets the parking position of the flying object 2A based on the current position of the spacecraft 1 and the direction of the sun Q1.

[0046] The control command unit 12 acquires the current position information of the flying object 2A, and based on the current position coordinates and the information on the stopping position of the flying object 2A, outputs a control command to move the flying object 2A to the stopping position set by the position setting unit 11. This control command is transmitted from the communication unit 13 to the communication unit 21 of the flying object 2A.

[0047] The drive control unit 22 of the flying vehicle 2A controls the propulsion engine 23 so that the magnetic field barrier 25 stays at the stopping position set by the position setting unit 11. Specifically, the propulsion engine 23 is controlled so that the magnetic field barrier 25 stays between the spacecraft 1 and the sun Q1 and at a predetermined distance (e.g., several hundred meters) from the spacecraft 1. That is, among cosmic radiation, cosmic radiation generated due to solar flares and the like comes from the direction of the sun Q1 in places where there is no influence of the earth's magnetic field and the like. For this reason, it is advisable to install the magnetic field barrier 25 between the spacecraft 1 and the sun Q1.

[0048] As a result, a magnetic field barrier 25 is positioned between the spacecraft 1 and the sun Q1, as shown in Figure 6. Furthermore, if the relative positional relationship between the spacecraft 1 and the sun Q1 changes, the position of the flying vehicle 2A is adjusted to follow this change.

[0049] When cosmic radiation generated by a solar flare or the like collides with or approaches the magnetic field barrier 25, the Lorentz force of the magnetic field barrier 25 acts, changing the trajectory of the cosmic radiation. As shown in Figure 6, if the longitudinal distance of the spacecraft 1 is 5 m and the magnetic field barrier 25 is parked at a position 100 m away from the spacecraft 1, the direction of the cosmic radiation can be changed by 1.4°, thereby preventing the spacecraft 1 from being exposed to the cosmic radiation.

[0050] On the other hand, if a magnetic field barrier is installed on the spacecraft 1 with a spacing of 1 m (position P1), the direction of the cosmic radiation must be changed by 68.2° to prevent cosmic radiation generated by the sun Q1 from irradiating the spacecraft 1. That is, by stopping the magnetic field barrier 25 at a position several hundred meters away from the spacecraft 1, it becomes possible to change the direction of the cosmic rays and prevent them from reaching the spacecraft 1 without generating a strong magnetic field in the magnetic field barrier 25. Furthermore, since there is no need to generate a strong magnetic field, the device configuration can be simplified and costs can be reduced.

[0051] Furthermore, if the magnetic field emitted by the magnetic field barrier 25 is the same, it is possible to protect the spacecraft 1 from higher energy cosmic radiation. It is also possible to reduce the impact of the magnetic field generated by the magnetic field barrier 25 on the external activities of the spacecraft 1. Furthermore, since there is no material that undergoes a nuclear reaction with cosmic radiation, it is possible to protect the spacecraft 1 from cosmic radiation without generating neutrons.

[0052] As described above, the radiation shielding system 101 according to the second embodiment uses the magnetic field barrier 25 as a shielding body. The propulsion engine 23 is controlled so that the magnetic field barrier 25 is positioned between the spacecraft 1 and the sun Q1 and at a distance of about several hundred meters from the spacecraft 1. Therefore, by changing the direction of the cosmic radiation by, for example, 1.4° using the magnetic field barrier 25, it is possible to dramatically reduce the amount of cosmic radiation that reaches the spacecraft 1. This reduces the effects on the human body, electronic devices, etc.

[0053] Furthermore, even if the relative position between the spacecraft 1 and the sun Q1 changes, the position of the flying vehicle 2A is adjusted to follow this change, thereby enabling stable shielding of the spacecraft 1 from cosmic radiation.

[0054] The control devices 31 and 32 of the present embodiment described above may be, for example, a general-purpose computer system including a CPU (Central Processing Unit, processor) 901, a memory 902, a storage 903 (HDD: Hard Disk Drive, SSD: Solid State Drive), a communication device 904, an input device 905, and an output device 906, as shown in Fig. 7. The memory 902 and the storage 903 are storage devices. In this computer system, the CPU 901 executes a predetermined program loaded on the memory 902, thereby realizing the functions of the control devices 31 and 32.

[0055] The control devices 31 and 32 may be implemented in one computer or in multiple computers. Furthermore, the control devices 31 and 32 may be virtual machines implemented in a computer.

[0056] The programs for the control devices 31 and 32 can be stored in a computer-readable recording medium such as an HDD, an SSD, a Universal Serial Bus (USB) memory, a Compact Disc (CD), or a Digital Versatile Disc (DVD), or can be distributed via a network. The computer-readable recording medium is, for example, a non-transitory recording medium.

[0057] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the present disclosure.

[0058] REFERENCE SIGNS LIST 1 Spacecraft 2, 2A Flying object 11 Position setting unit 12 Control command unit 13 Communication unit 21 Communication unit 22 Drive control unit 23 Propulsion engine (flight drive source) 24 Shielding material (shielding body) 25 Magnetic field barrier (shielding body) 31, 32 Control device 100, 101 Radiation shielding system Q1 Sun

Claims

1. A radiation shielding system that shields a spacecraft from radiation incoming to it, comprising: a flying body; and a control device mounted on the spacecraft, wherein the flying body comprises: a flight drive source; a drive control unit that controls the drive of the flight drive source; and a shield that shields from radiation, and the control device comprises: a position setting unit that sets a position between the spacecraft and the sun, a predetermined distance away from the spacecraft, as the parking position of the flying body; and a control command unit that outputs a control command to the drive control unit so that the flying body stays at the parking position.

2. The radiation shielding system according to claim 1, wherein the predetermined distance is 100 m or more.

3. The radiation shielding system of claim 1, wherein the shielding comprises a shielding material having at least one of tantalum, tungsten, lead, and aluminum.

4. The radiation shielding system according to claim 1, wherein the shielding body includes a magnetic field barrier that changes the direction of incoming radiation.

5. The radiation shielding system of claim 4, wherein the magnetic field barrier includes at least one of a permanent magnet, an electromagnet, and a superconducting magnet.

6. The radiation shielding system according to claim 1, wherein the flying object is launched from the spacecraft.

7. A flying vehicle that shields a spacecraft from radiation incoming thereto, comprising: a flight drive source; a shield that shields the radiation; and a drive control unit that controls the drive of the flight drive source so that the shield stays at a position a predetermined distance away from the spacecraft between the spacecraft and the sun.

8. A radiation shielding method for shielding a spacecraft from radiation entering the spacecraft, comprising: a position setting unit setting a position between the spacecraft and the sun, a predetermined distance away from the spacecraft, as a position for stopping the flying object; and a control command unit outputting a control command to a drive control unit so that the flying object stops at the position set by the position setting unit.

Images