Locating a mining site using neutron prospecting

Abstract

A helium-3 detector apparatus is disclosed that generally includes a neutron shield between a thermal neutron source and a thermal neutron detector, where the thermal neutron source, thermal neutron detector, and neutron shield all rest on a metal platform. In operation, when the helium-3 detector apparatus is on or near the ground, the thermal neutron source emits thermal neutrons. Some of the thermal neutrons from the neutron source are backscattered from the surface soil layer to the neutron detector, where a baseline count level is recorded. When helium-3 is present in the surface soil layer, some of the thermal neutrons are absorbed by the helium-3, thereby decreasing the count rate detected. When integrated with a detection vehicle, the helium-3 detector moves around and compares the count rate at each location. In this way, the high and low levels of helium-3 in the surface soil layer can be mapped to indicate target areas for helium-3 mining.

Description

TECHNICAL FIELD

[0001] The present invention relates generally to the use of neutron detection technology to identify mining sites in order to map areas with high concentrations of helium-3 for mining. BACKGROUND

[0002] Identifying the concentration of target material (e.g., helium-3) to be mined prior to commencing mining operations is of great value. Having a general understanding of the concentration of target elements within a mining site allows for the development of more efficient strategies for extraction methods, thereby minimizing unnecessary loss of time and expense. By at least making a rough assessment of the concentration of target material, mining companies can employ more targeted and efficient extraction techniques, reducing the need for large-scale excavation and processing. Such an approach not only saves valuable resources for mining target material but also lessens the destruction of the entire mining site.

[0003] Furthermore, having advance knowledge of the concentration of target material has a significant impact on the economic viability of a mining project. An accurate assessment allows for an informed decision as to whether to proceed with mining, thereby avoiding costly attempts where the concentration of target material can be too low to yield a minimum return. By identifying areas of high target material concentration, mining operations can more effectively utilize their resource allocation, directing investment to sites with higher concentrations, thereby maximizing their operational efficiency and profitability while minimizing time loss and unnecessary mining costs. Most importantly, the value of identifying the concentration of target material prior to mining lies in its ability to ensure a more efficient approach to the extraction of target material.

[0004] Embodiments of the present invention are generally directed to innovations related to the subject matter. SUMMARY

[0005] The present invention relates generally to a device for mining and collecting helium-3 and other target gaseous elements from extraterrestrial bodies in an ultra-low pressure environment. Ultra-low pressure is defined as below 7 mbar.

[0006] In this case, some embodiments of the present invention contemplate a helium-3 detection device that includes a thermal neutron source and a thermal neutron detector. More specifically, the thermal neutron source can include a thermal neutron emitter encapsulated in a hydrogen-rich material, where the thermal neutron source is configured to emit thermal neutrons in all directions. The thermal neutron detector can be configured to detect a concentration of thermal neutrons. In this device, a neutron shield is positioned between the thermal neutron source and the thermal neutron detector. The neutron shield is configured to block some of the thermal neutrons emitted from the thermal neutron source that are aimed at the thermal neutron detector (e.g., attenuate at least 90% of the neutrons between the shield and the thermal neutron detector). A power source, such as a battery or a solar system, is configured to provide power to the thermal neutron source and the thermal neutron detector. The metal plate has a perimeter, i.e., the side walls of the metal plate are bounded by four sides. The thermal neutron source, the thermal neutron detector, and the neutron shield are disposed within the perimeter of the metal plate.

[0007] Another embodiment of the present invention contemplates a helium-3 detection system that generally includes a thermal neutron detector for sensing a number of neutrons emitted from a thermal neutron source to assess a concentration of helium-3 in a topsoil layer or other granular soil. More specifically, this embodiment contemplates that the thermal neutron source is configured to emit thermal neutrons in all directions, where the thermal neutron detection system is configured to detect a neutron concentration of thermal neutrons backscattered from the granular soil. A neutron shield is positioned between the thermal neutron source and the thermal neutron detector to isolate the detected neutrons from the topsoil layer to assess the number or concentration of helium-3 in the topsoil layer. The system can include a power source, such as a battery, to provide power to the thermal neutron source and the thermal neutron detection system. The neutron shield, the thermal neutron source, and the thermal neutron detection system are contemplated to be disposed on a metal plate that is configured to be placed within 10 centimeters of the surface of the granular soil.

[0008] Another embodiment of the present invention contemplates a device for detecting helium-3 in a topsoil layer of the moon. The device can include a neutron source configured to emit thermal neutrons, a neutron detector configured to detect a concentration of neutrons backscattered from the topsoil layer, and a neutron shield positioned between the neutron source and the neutron detector. The neutron shield is configured to block at least some of the neutrons in the line of sight between the neutron source and the neutron detector. The device can also include a power source configured to provide power to the thermal neutron source, the thermal neutron detection system, and a transmitter. The transmitter is configured to transmit the neutron concentration to a remote receiver. The neutron shield, the thermal neutron source, and the thermal neutron detection system are contemplated to be disposed on a metal plate. The device is also contemplated to be moved to different locations on the surface of the moon via a transport machine. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1A is a line drawing of an embodiment of a transport machine and helium-3 detector consistent with embodiments of the present invention;

[0010] Figure 1B is a schematic illustration of the use of a helium-3 detector device carried on a hopper transport to map an area on the moon consistent with embodiments of the present invention;

[0011] Figures 2A-2C is a line drawing depicting a helium-3 detector device consistent with embodiments of the present invention;

[0012] Figure 2D is a block diagram depicting an embodiment of a thermal neutron source along section line B-B consistent with embodiments of the present invention;

[0013] Figure 2E is a line drawing of a cross section of a helium-3 detector device along section line A-A consistent with embodiments of the present invention; and

[0014] Figure 3 is a line drawing of another embodiment of a helium-3 detector device with a handle consistent with embodiments of the present invention. DETAILED DESCRIPTION

[0015] First, the present disclosure is presented by way of example only and is not limited by the exemplary embodiments described herein. Thus, although the means described herein are presented in connection with exemplary embodiments, it is to be understood that the principles herein can be applied to other similar constructions related to the subject matter of the present application. The phrases "in one embodiment," "according to one embodiment," etc., as may be used herein do not necessarily refer to the same embodiment, although they can. The phrases "in one embodiment," "according to one embodiment," etc., can refer to a particular previously described embodiment as well as a variation on a previously described embodiment that is apparent to the skilled artisan by virtue of the teachings herein. It is contemplated that the principles herein can be applied to other similar constructions. The terms "comprises," "comprising," "includes," and "including," as used herein, are meant to be interpreted in an open-ended manner, i.e., they are meant to encompass the terms "consisting of" and "consisting essentially of." Furthermore, the term "substantially" is used herein to represent the inherent tolerance in the manufacturing process, as well as the measurement of other physical properties, as known to those skilled in the art. The term "substantially" is meant to encompass the term "more or less." For example, a shape that is "substantially circular" is intended to mean a shape that is more or less circular, and is not intended to mean a perfect circle. Thus, if "substantially" is not specified, it is assumed that substantially means + / - 2.5% of the exact value. The term "connected to" as used herein is to be interpreted as a first element being physically linked or attached to a second element, and not as "means plus function" as in "means for attaching." In fact, unless the term is expressly used with "means" followed by a gerund form of the verb, the term is not to be interpreted in accordance with 35 U.S.C. § 112(f). In the following description, like reference numerals can be used to identify similar or identical structures.

[0016] With respect to the drawings, it is noted that the drawings can not be to scale and are generally intended for illustrative purposes only. Descriptive terminology such as "above," "below," "top," "bottom," "horizontal," "vertical," "left," "right," etc., can be used in relation to the various views or conventions provided in the drawings, as typically understood by a person of ordinary skill in the art to enhance the reader's understanding, and are in no way intended to limit. All embodiments described herein are considered operable regardless of overall physical orientation, unless otherwise specifically described, e.g., elements that rely on gravity for operation.

[0017] Embodiments are described herein for identifying target materials in very low pressure and low gravity environments. A very low pressure environment is defined herein as being below 7 mbar, while the pressure at sea level on Earth is about 1 bar. Low gravity is defined herein as being at most 4 m / sec 2Various aspects of the present invention contemplate the mining of gaseous atoms and molecules on extraterrestrial bodies such as the Moon, asteroids, satellites orbiting other planets, Mars, and the like. Many such extraterrestrial bodies have little or no ambient pressure at or within a few meters of their surface, and depending on the size of the extraterrestrial body, they typically have a gravitational force that is significantly lower than that of Earth.

[0018] While embodiments of the present invention can be used in conjunction with many different extraterrestrial bodies, one purpose of the present invention is to focus on the mining of gaseous atoms and molecules (materials) from the Moon. The lunar atmosphere (exosphere) has a pressure of about 3 x 10 -15 -6 bar and can range in temperature between 20° and 400° Kelvin. To continue to explore the Moon and to maintain long-term habitation on the Moon, extracting or otherwise mining important gaseous materials such as oxygen, nitrogen, hydrogen, and helium from the Moon can reduce the dependency on transporting such gaseous materials from Earth. Furthermore, helium-3 (He-3) is a light stable isotope of helium that has two protons and one neutron and is promising as an important component of fusion reactions, and the content of helium-3 on the Moon is much higher than that of Earth. In some estimates, the content of helium-3 on the Moon is more than a thousand times higher than that of Earth, making the Moon a better target for obtaining helium-3.

[0019] Some embodiments of the present invention contemplate identifying concentrations of target materials on or within a few feet of the surface of the Moon by probing the concentration of neutrons backscattered from the lunar regolith (or simply "regolith"). In this way, the target materials to be mined can be mapped within a mining area of interest.

[0020] Accordingly, some embodiments of the present invention contemplate a helium-3 probe device that generally includes a neutron shield disposed between a thermal neutron source and three thermal neutron detectors, all of which rest on a metal platform. In operation, when the helium-3 probe device is placed directly on the ground (regolith) or slightly above the ground, thermal neutrons are emitted from the thermal neutron source. Some of the thermal neutrons from the neutron source will be backscattered from the regolith and will be detected by the thermal neutron detection system, thereby recording a baseline count level. When helium-3 is present in the regolith, some of the thermal neutrons will be absorbed by the helium-3, thereby reducing the count rate detected. When integrated into a probe vehicle, the device can be moved around and compare the count rate at each location, or the probe vehicle can be slowly crawled along the ground. In this way, the high and low levels of helium-3 in the regolith can be mapped.

[0021] Referring to the drawings, Figure 1Ais a line drawing of an embodiment of a transport and helium-3 detector 100 consistent with embodiments of the present invention. The transport and helium-3 detector 100 generally includes a helium-3 (He-3) detector 200 that is supported or otherwise carried by a rover 102. The rover 102 includes a locomotion device, which in this embodiment is a wheel 106 mounted on a suspension system 105, but which can simply include a track, robotic legs, or some other type of locomotion device to transport the helium-3 detector 200 to different locations on the lunar surface. As shown, the helium-3 detector 200 rests on top of a metal plate 110 and is substantially encased by a shroud 108. An antenna 212 extending from the shroud 108 is connected to a transmitter and can be connected to a transceiver (not shown). The antenna 212 facilitates at least one-way communication with a receiver remote from the rover 102 by, for example, radio frequency (RF). Other embodiments contemplate integrating the helium-3 detector 200 with a low-gravity hopper 120 as shown in Figure 1B

[0022] More specifically, Figure 1B is a schematic diagram of using a helium-3 detector device carried on a hopper transport to map out areas on the moon consistent with embodiments of the present invention. This embodiment contemplates a hopper transport 120 that is capable of taking off from a first location 152 after evaluating the helium-3 concentration at the first location 152, landing at a second location 154 and evaluating the helium-3 concentration at the second location 154, and then taking off again to a third location 156 to evaluate the helium-3 concentration at the third location 156. In this manner, a portion of the lunar surface can be mapped out for helium-3 concentrations to pinpoint ideal locations for mining helium-3. Since the gravity on the moon is about 1 / 6 of that on Earth, the energy required for the hopper 120 to take off (and land) is significantly reduced. The hopper transport 120 can be a spring-loaded vehicle or gondola and can use gyroscopes or jet packs to remain level (upright orientation while hopping). Optionally, the hopper transport 120 can be equipped with rockets to hop from location 154 to location 156.

[0023] Figures 2A-2C is a line drawing depicting a helium-3 detector device 200 consistent with embodiments of the present invention. Figure 2A is an isometric line drawing of the main components of a helium-3 detector 200, as Figure 2A ​As shown, the helium-3 detector 200 includes a neutron shield 206 positioned between the thermal neutron source 202 and the three thermal neutron detectors 204. The neutron shield 206 blocks the line of sight 218 of a portion of the thermal neutrons 222 emitted from the thermal neutron source 202 from affecting the thermal neutron detectors 204. The line of sight 218 is defined as a straight line along which an observer (in this case the thermal neutron source 202) can unobstructed "see" the thermal neutron detector device 204. In one embodiment, the neutron shield 206 is envisioned to be two 1-2 inch thick Boronated HDPE (high density polyethylene) produced by EMCO Industrial Plastics, LLC, headquartered in Cedar Grove, New Jersey. Boronated HDPE is specifically designed for nuclear shielding applications. This material employs 5% by weight of boron to shield neutrons in a variety of applications, including high intensity X-ray, cancer treatment facilities, hospitals, nuclear submarines, and nuclear power plants. A 1 inch thick sheet should attenuate the flux of thermal neutrons 222 in the line of sight 218 to about 5% on the other side of the neutron shield 206, while two 1 inch thick sheets should attenuate the flux of thermal neutrons 222 in the line of sight 218 to about 0.025% on the other side of the neutron shield 206. In other words, the two sheets should attenuate or otherwise stop 99.25% of the neutrons from reaching the thermal neutron detectors 204. In the present embodiment, the two sheets 206A and 206B are separated by a lead sheet 207. As further shown, the neutron shield 206, the thermal neutron source 202, the thermal neutron detectors 204, the battery pack 210, the antenna 212, and the antenna connection wire 213 are all supported by the metal plate 110.

[0024] Figure 2B is an exemplary line drawing depicting the helium-3 detector device 200 in Figure 2A but the line drawing does not show the neutron shield 206 in order to show the line of sight 218 between the thermal neutron source 202 and the thermal neutron detector device 204. The line of sight 218 is the direct path between the thermal neutron source 202 and the three thermal neutron detectors that essentially make up the thermal neutron detector device 204.

[0025] The thermal neutron detector device 204 is sensitive to the number of neutrons 222 impinging on the detector device 204 and can therefore provide information about the concentration of neutrons it encounters. Several commercially available thermal neutron detectors 204 exist, including the BF3 counter tube produced by Mirion Technologies, headquartered in Atlanta, Georgia. This thermal neutron detector uses a boron trifluoride (BF3) neutron counter. The neutron sensitivity of these proportional counters is achieved by filling the tube with boron trifluoride gas made from a high concentration of boron-10 inside the tube. Thermal neutrons react with the isotope boron-10, emitting alpha particles, which create ionization (electrons and gas ions) in the gas fill of the detector. In the electric field between the electrodes, these charged particles are accelerated and undergo secondary ionization. This so-called "gas amplification" increases the amount of charge generated in the tube proportionally.

[0026] Figure 2C is a top view sketch of the helium-3 detector device 200, depicting the elements with respect to the section lines A-A and B-B. For reference, the electronics housing 216 is shown, which houses the computing electronics required to operate the various electrical elements comprised by the helium-3 detector 200, and the communication device housing 214, which houses the transmitter or possibly a transceiver. The antenna 212 is connected to the communication circuitry in the communication device housing 214. Also shown are the battery 210, the thermal neutron source 202, the neutron shield 206, and the thermal neutron detector device 204. The thermal neutron detector device 204 comprises three detectors in this embodiment, but can also have as few as one detector or more as needed. The section line A-A bisects the metal plate 110, the thermal neutron source 202, the neutron shield 206, and the thermal neutron detector device 204 substantially in half. The section line B-B, which is orthogonal to the section line A-A, bisects the thermal neutron source 202.

[0027] Figure 2Dis a block diagram depicting an embodiment of a thermal neutron source 202 along section line B-B consistent with embodiments of the present application. This embodiment of the thermal neutron source 202 can include an Americium-Beryllium (AmBe) neutron source (core) 232 encapsulated within a hydrogen-rich shell 230, which in this embodiment is envisioned as a polyethylene shell. The polyethylene shell 230 thermalizes the neutrons by reducing their energy through collisions with hydrogen nuclei in the polyethylene. The AmBe thermal neutron source is commercially available from QSA Global, Inc. of Burlington, MA. An alternative thermal neutron source 202 includes an integrated moderated neutron generator such as a deuterium-tritium or deuterium-deuterium neutron generator, which are commercially available from Adelphi Technology, Inc. of Redwood City, CA. Accordingly, some embodiments of the present application envision the thermal neutron source 202 as an off-the-shelf, readily commercially available thermal neutron source.

[0028] Figure 2E is a plot of a cross-section of the helium-3 probe apparatus 200 along section line A-A consistent with embodiments of the present application. It is known that helium-3 absorbs neutrons. Accordingly, the concentration of neutrons that penetrate the helium-3 is reduced accordingly. In this apparatus 200, some of the neutrons emitted from the thermal neutron source 202 as indicated by arrows 219 are backscattered from the regolith 112 to the thermal neutron probe 204 (see narrow arrows 220), while some of the arrows 219 are absorbed by the helium-3 present in the regolith 112. Accordingly, the concentration of helium-3 in the regolith 112 will be inversely proportional to the concentration of neutrons detected by the thermal neutron probe 204 relative to the concentration of neutrons emitted by the thermal neutron source 202. In other words, the higher the concentration of helium-3 in the regolith 112, the fewer the number of neutrons that reach the thermal neutron probe 204, which is illustrated by the narrow arrows 220. The neutron shield 206 blocks the line of sight 218 of the neutron probe 204 from neutrons, preventing them from hitting the neutron probe 204, thereby improving the resolution of the backscattered neutron concentration 220. The metal plate 110, which in some embodiments is aluminum, does not change the number of neutrons (emitted by the thermal neutron source 202) that penetrate into the regolith 112. According to this apparatus 200, the concentration of neutrons detected by the thermal neutron probe 204 is compared to the concentration of neutrons produced by the thermal neutron source 202 in order to provide an indication of the concentration of helium-3 in the regolith 112 region. Although an accurate amount of helium-3 can not be obtained, a relative amount can be obtained, which is sufficient to identify and map highly interesting regions on the moon for helium-3 mining based on sampling of different regions / areas on the moon. Data collection and calculations can be performed by the electronic computer system 216 on the helium-3 probe apparatus 200.

[0029] Figure 3This is a line drawing of another embodiment of the helium-3 detector device 200 including a handle 224, which can be used to transport the helium-3 detector device 200 from one location to another manually or by means of a robot, or otherwise.

[0030] In light of the present description, the following are examples of certain embodiments that exemplarily supplement some of the device embodiments discussed above and illustrated in the figures to aid the reader's understanding. Therefore, the elements mentioned below are examples provided to aid in understanding the invention and should not be considered limiting. The reader will understand that the elements and constructions below are interchangeable within the scope and spirit of the invention. Exemplary embodiments may include the elements in the figures.

[0031] In this context, some embodiments of the present invention envision as follows: Figures 2A-2E The helium-3 detection device 200 shown includes a thermal neutron source 202 and a thermal neutron detector 204. More specifically, the thermal neutron source 202 may include a thermal neutron emitter 232 encapsulated in a hydrogen-rich material 230, wherein the thermal neutron source 202 is configured to emit thermal neutrons 222 in various directions (see [reference]). Figure 2E The thermal neutron detector 204 can be configured to detect the concentration 220 of thermal neutrons 218. In the device 200, a neutron shield 206 is placed between the thermal neutron source 202 and the thermal neutron detector 204. The neutron shield 206 is configured to block some of the thermal neutrons 222 emitted from the thermal neutron source 202 that are aimed at the thermal neutron detector 204 (e.g., attenuating at least 90% of the neutrons 222 located between the shield 206 and the thermal neutron detector 204). A power source 210, such as a battery or a solar system, is configured to power the thermal neutron source 202 and the thermal neutron detector 204. The metal plate 110 has a perimeter 114, i.e., the sidewall boundary of the metal plate 110 shown by its four sides 114. The thermal neutron source 202, the thermal neutron detector 204, and the neutron shield 206 are disposed within the perimeter 114 of the metal plate 110.

[0032] In another embodiment, the probe 102 is conceived to support the helium-3 detection device 200, wherein the probe 102 positions the metal plate 110 within 10 centimeters of the surface 112A of the granular soil 112. The helium-3 detection device 200 is conceived to have a concentration 220 influenced by the helium-3 concentration in the granular soil 112.

[0033] In another embodiment of the helium-3 detection device 200, the metal plate 110 is made of aluminum.

[0034] The helium-3 detection apparatus 200 can also include wireless communicators 212 and 214 configured to transmit the concentration 220 to a receiver, such as a receiver at a remote hub or remote site, which evaluates the concentration 220 for each sampling location (from 152 and 154 to 156, as shown). Figure 1B In some embodiments, the concentration 220 can be determined with respect to time.

[0035] In another embodiment of the helium-3 detection apparatus 200, the metal plate 110 is at least a portion of a detection cart base of the detection cart 102.

[0036] The helium-3 detection apparatus 200 also contemplates that the metal plate 110 is positioned less than 10 centimeters from the granular surface 112A when the thermal neutron source 202 is emitting neutrons 222.

[0037] The helium-3 detection apparatus 200 contemplates an embodiment in which the metal plate 110 includes a handle 224 configured to be carried by at least one person or a robot.

[0038] The helium-3 detection apparatus 200 contemplates an embodiment in which the metal plate 110 is attached to the low gravity jumper 120.

[0039] Another embodiment of the present invention contemplates a helium-3 detection system 200 generally including a thermal neutron detector 204 for sensing the number of neutrons 222 emitted from a thermal neutron source 202 to evaluate the concentration of helium-3 in the topsoil 112 or other granular soil. More specifically, this embodiment contemplates that the thermal neutron source 202 is configured to emit thermal neutrons 222 in various directions, wherein the thermal neutron detection system 204 is configured to detect the concentration 220 of thermal neutrons 222 backscattered from the granular soil 112. A neutron shield 206 is positioned between the thermal neutron source 202 and the thermal neutron detector 204 to isolate the neutrons detected from the topsoil 112 to evaluate the number or concentration of helium-3 in the topsoil 112. The system can include a power source 210, such as a battery, to power the thermal neutron source 202 and the thermal neutron detection system 204. The neutron shield 206, the thermal neutron source 202, and the thermal neutron detection system 204 are contemplated to be disposed on a metal plate 110 configured to be placed within 10 centimeters of the surface 112A of the granular soil 112.

[0040] The helium-3 detection system 200 also contemplates that the neutron shield 206 is configured to block at least 90% of the thermal neutrons 222 emitted from the thermal neutron source 202 that are aimed 218 at the thermal neutron detection system 204.

[0041] The helium-3 detection system 200 also contemplates that the concentration of neutrons 220 detected by the thermal neutron detection system 204 is inversely proportional to the concentration of helium-3 in the particulate soil 112.

[0042] The helium-3 detection system 200 contemplates an embodiment in which the neutron shield 206 is a boronized shield.

[0043] The helium-3 detection system embodiment 200 can also include a transmitter 214 configured to transmit the concentration of neutrons 220 to a remote receiver.

[0044] The helium-3 detection system 200 contemplates using the helium-3 detection system 200 to map out areas of helium-3 concentration by moving it to different locations on the surface 112A of the celestial body 122 (from 152 and 154 to 156, as shown) via a conveyance selected from the group consisting of the detection vehicle 102, the low gravity hopper 120, or a robot (not shown). Figure 1B

[0045] The helium-3 detection system 200 contemplates that the neutron shield 206 is 1 to 4 inches thick, depending on the amount of neutron attenuation required on the thermal neutron detection system side of the neutron shield 206.

[0046] Another embodiment of the present invention contemplates a device 200 for detecting helium-3 in a surface layer 112 of the moon 122. The device 220 can include a neutron source 202 configured to emit thermal neutrons 222, a neutron detector 204 configured to detect a concentration of neutrons 220 backscattered 220 from the surface layer 112 of the moon 122, and a neutron shield 206 disposed between the neutron source 202 and the neutron detector 204. The neutron shield 206 is configured to block at least some of the neutrons 222 in a line of sight 218 between the neutron source 202 and the neutron detector 204. The device 200 can also include a power source 210 configured to provide power to the thermal neutron source 202, the thermal neutron detection system 204, and transmitters 212 and 214. The transmitters 212 and 214 are configured to transmit the concentration of neutrons 220 to a remote receiver. The neutron shield 206, the thermal neutron source 202, and the thermal neutron detection system 204 are contemplated to be disposed on the metal sheet 110. The device 200 also contemplates being moved to different locations on the surface 112A of the moon 122 (from 152 and 154 to 156, as shown) via a conveyance 102 or 120. Figure 1B

[0047] In this device 200, the neutron shield 206 is contemplated to be thick enough and contain enough attenuating material, such as boron, to attenuate at least 95% of the neutrons 222.

[0048] ​​In the device 200, the concentration of neutrons 220 detected by the neutron detector 204 is inversely proportional to the concentration of helium-3 in the topsoil layer 112.

[0049] These exemplary embodiments are not an exhaustive chain of contemplated embodiments consistent with embodiments of the present invention presented throughout the description. In other words, many other embodiments are described herein that are not necessarily demonstrated in the device embodiments immediately presented above.

[0050] It should be understood that, although numerous characteristics and advantages of various embodiments of the present invention and structures and functions of various embodiments of the present invention are set forth in the foregoing description, the disclosure is illustrative only, and changes can be made in detail, especially in matters of structure and arrangement of parts within the principles of the concepts expressed by the language of the appended claims as interpreted throughout the specification. For example, the orientations of the elements and the board can include other geometric shapes which are not explicitly shown in the above embodiments, but which are capable of maintaining the same functionality without deviating from the scope and spirit of the present invention. Likewise, the materials and structures of the neutron shield can be different, but still achieve the same purpose without deviating from the scope and spirit of the present invention. Furthermore, electronic and computing devices capable of achieving the functionality of the helium-3 detection system are not described in detail as they either already exist or can be easily constructed by those skilled in the art.

[0051] It is clear that the present invention well adapts to the mentioned purposes and advantages, as well as those inherent to it. Although the presently preferred embodiments have been described for the purposes of this disclosure, many modifications can be made which are readily apparent to those skilled in the art, and which are included in the spirit of the disclosed invention, and are defined in the appended claims.

Claims

1. A helium-3 detection apparatus comprising: a thermal neutron source comprising a thermal neutron emitter encapsulated in a hydrogen-rich material, the thermal neutron source configured to emit thermal neutrons in all directions; a thermal neutron detector configured to detect a concentration of thermal neutrons; a neutron shield disposed between the thermal neutron source and the thermal neutron detector, the neutron shield configured to block at least 90% of thermal neutrons emitted from the thermal neutron source that are aimed at the thermal neutron detector; a power source configured to provide power to the thermal neutron source and the thermal neutron detector; and a metal plate defining a perimeter, wherein the thermal neutron source, the thermal neutron detector, and the neutron shield are disposed within the perimeter of the metal plate.

2. The helium-3 detection apparatus of claim 1, further comprising a detection cart configured to position the metal plate within 10 centimeters of a surface of a granular soil.

3. The helium-3 detection apparatus of claim 2, further comprising a computer system configured to correlate the concentration of thermal neutrons to a concentration of helium-3 in the granular soil.

4. The helium-3 detection apparatus of claim 1, wherein the metal plate is aluminum.

5. The helium-3 detection apparatus of claim 1, further comprising a wireless communicator configured to transmit the concentration of thermal neutrons.

6. The helium-3 detection apparatus of claim 5, wherein the concentration of thermal neutrons is relative to time.

7. The helium-3 detection apparatus of claim 1, further comprising a detection cart comprising a detection cart base having the metal plate.

8. The helium-3 detection apparatus of claim 1, wherein the metal plate is positioned less than 10 centimeters from a granular surface when the thermal neutron source emits thermal neutrons.

9. The helium-3 detection apparatus of claim 1, wherein the metal plate comprises a handle configured to be carried by at least one person or a robot.

10. The helium-3 detection apparatus of claim 1, further comprising a low gravity hopper.

11. A helium-3 detection system comprising: a thermal neutron source configured to emit thermal neutrons in all directions; a thermal neutron detection system configured to detect a neutron concentration of thermal neutrons backscattered from a granular soil; a neutron shield disposed between the thermal neutron source and the thermal neutron detection system, the neutron shield configured to block at least 90% of thermal neutrons emitted from the thermal neutron source that are aimed at the thermal neutron detection system; a power source configured to provide power to the thermal neutron source and the thermal neutron detection system; and a metal plate housing the neutron shield, the thermal neutron source, and the thermal neutron detection system.

12. The helium-3 detection system of claim 11, further comprising a computer system configured to calculate a concentration of helium-3 in the granular soil inversely proportional to the neutron concentration of thermal neutrons.

13. The helium-3 detection system of claim 11, wherein the neutron shield is a boronized shield. ​ ​ 14. The helium-3 detection system of claim 11, further comprising a transmitter configured to transmit the neutron concentration of thermal neutrons.

15. The helium-3 detection system of claim 11, further comprising a vehicle configured to move to different locations on the surface of the celestial body, the vehicle selected from the group consisting of a rover, a low gravity hopper, and a robot.

16. The helium-3 detection system of claim 11, wherein the neutron shield is 1 to 4 inches thick.

17. An apparatus for detecting helium-3 in a regolith on the moon, the apparatus comprising: a neutron source configured to emit thermal neutrons; a neutron detector configured to detect a neutron concentration of thermal neutrons backscattered from the regolith; a neutron shield disposed between the neutron source and the neutron detector, the neutron shield configured to block at least 90% of the thermal neutrons in a line of sight between the neutron source and the neutron detector; a power source configured to provide power to the neutron source and the neutron detector; a transmitter configured to transmit the neutron concentration of thermal neutrons; a metal plate comprising the neutron shield, the neutron source, and the neutron detector disposed on the metal plate; and a vehicle configured to move the apparatus to different locations on the surface of the moon.

18. The apparatus of claim 17, further comprising a computer system configured to calculate a concentration of helium-3 in the regolith indirectly from the neutron concentration of thermal neutrons. ​

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