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Water resources on the Moon are a critical component of international strategies for exploration of the solar system and space-based economic development. Liquid water is essential for human life support and propellant generation. Extreme Lunar conditions of near-vacuum and low temperature preclude the natural presence of liquid water; and they provide the thermodynamic context for water occurrence and its potential extraction. Ice crystals were observed by LCROSS and are inferred to reside in pore spaces of lunar regolith or at the surface in places. Any system proposed for lunar ice mining by induced sublimation needs to address potential vapor loss to the ambient near-vacuum; regolith cohesiveness; low regolith thermal conductivity; negligible sublimation rates below-200K; low rates of vapor advection-diffusion through porous regolith; and pressurization due to sublimation that causes redeposition. All of these obstacles have potential solutions with available technologies, but they must be designed within power availability constraints and with the potential to scale up to the resource needs of a growing space economy.

期刊论文 2025-03-01 DOI: 10.1016/j.actaastro.2024.12.011 ISSN: 0094-5765

Water resources are essential to human exploration in deep space or the establishment of long-term lunar habitation. Ice discovered on the Moon may be useful in future missions to the lunar surface, necessitating the consideration of in situ resource utilization if it is present in sufficient amounts. Extraction of ice can cause the regolith to settle, which can lead to unintended structural damage. Therefore, any settlement resulting from ice extraction should be understood from a geotechnical perspective. This work reports on experimental investigation of the potential settlement caused by the extraction of ice from lunar regolith simulant containing different textures of ice. The KLS-1 simulant was prepared with different water contents and ice textures. Significant settlement occurred in simulant-ice mixtures with initial water contents of 5-10%.

期刊论文 2024-03-01 DOI: 10.3390/aerospace11030207

Water resources are essential to human exploration in deep space or the establishment of long-term lunar habitation. Ice discovered on the Moon may be useful in future missions to the lunar surface, necessitating the consideration of in situ resource utilization if it is present in sufficient amounts. Extraction of ice can cause the regolith to settle, which can lead to unintended structural damage. Therefore, any settlement resulting from ice extraction should be understood from a geotechnical perspective. This work reports on experimental investigation of the potential settlement caused by the extraction of ice from lunar regolith simulant containing different textures of ice. The KLS-1 simulant was prepared with different water contents and ice textures. Significant settlement occurred in simulant-ice mixtures with initial water contents of 5-10%.

期刊论文 2024-03-01 DOI: 10.3390/aerospace11030207

Identifying the best technique for extracting water ice deposits in permanently shadowed regions at the lunar poles will be crucial in determining how successful a long-term or permanent settlement at these locations will be for future scientific and technology missions. This study uses a low-power microwave heating method to extract water from icy lunar simulants. Samples of lunar highland and mare simulants at different water contents (3-15 wt %) were heated using 250 W, 2.45 GHz microwaves. A maximum of 67 +/- 5% [2SD] of the water was extracted during heating runs of 25 min. Water was extracted more efficiently from the highland simulant than from the mare simulant. A significant reason for the different efficiency of water extraction in icy lunar simulants was the differing porosity of the samples made from different simulants. Pore space filled with ice leads to a reduced contact area between grains and an increased area of free ice, which causes poor heating performance. The results indicated that differences in chemical composition between the simulants had a negligible effect on water extraction, as the contact area between grains seems to dominate water extraction. This study found that low-power microwave heating is an effective technique for extracting water from cryogenic Icy simulants. It was also found that using a simple input energy principle (Input Energy = Absorbed Power x Heating Time) to es-timate the additional heating time was sufficient to overcome inefficient heating due to differing absorbed powers. For undersaturated samples, microwave heating was an efficient heating mechanism, but is less efficient for saturated samples where alternative heating methods may be more efficient at melting free ice before employing microwave heating.

期刊论文 2023-08-01 DOI: 10.1016/j.actaastro.2023.04.035 ISSN: 0094-5765

Technological advancements have revolutionized the space industry, facilitating deep space exploration using CubeSats. One objective is to locate potential life-support elements, such as water, on extraterrestrial planets. Water possesses a distinct spectral signature at 183 GHz, useful in remote sensing and environmental monitoring applications. Detecting this signature provides crucial information about water and ice presence and distribution on celestial bodies, aiding future exploration and colonization efforts. Mostly in space remote sensing uses corrugated horn antennae due to high gain and radiation patterns but fabrication of corrugated antenna is very challenging or even impossible in some cases. To ease this challenge, in our research we propose ideas to transform a corrugated horn antenna into a smooth-walled design by using MATLAB Cubic smoothing Splines algorithms. We compare simulation results between smooth-walled and corrugated antennas, and we can see some improvements in insertion losses, Voltage Standing Wave ratio (VSWR), and gain. We also manufactured this 183 GHz antenna using a commercially available 3D printer by utilizing Acrylonitrile Butadiene Styrene (ABS) material. The antenna surface was then coated with a thin layer of copper using conductive paint. In the end, we practically evaluate smooth-walled antenna functionality and compare it with the theriacal results. Validating the antenna's functionality proposes a cost-effective and accessible production method to be used in a CubeSat engineering model or university students' project.

期刊论文 2023-08-01 DOI: 10.3390/app13169364

In recent years, the Moon, as the closest celestial body to the Earth, has become the foremost target of human exploration outward. Some lunar exploration missions and studies have shown that ice may exist in the polar regions of the Moon. Water is very important for human survival. The ice mining and utilization is based on the understanding of the sublimation mechanism. Simulation of ground-based tests is an effective means to explore the sublimation of ice. Therefore, in this paper, the thermal environment of Shackleton Crater and the particle size distribution of typical lunar soils are analyzed as the basis of parameter settings for the ground test. Four operating conditions are established for ground tests, including the influence of heat sink temperature, vacuum level, particle size distribution and dry soil density. The larger the radiation heat flow, the higher the heat sink temperature, the smaller the vacuum degree, the larger the average particle size, resulting in a larger sublimation rate. The decrease of density makes the sublimation process faster and then slower. The sublimation process proceeds fastest when the dry soil density is 1200 kg/m3. The heat sink temperature has the greatest effect on the sublimation process, and the vacuum has the least effect. When the radiation heat flow ranges from 39.01 W/m2 to 45.63 W/m2 at the heat sink temperature of 120 K, the maximum sublimation rate is 5.79E-15 kg/s, the maximum sublimation area is 1.93E-9 m2 and the maximum sublimation heat flow is 1.59E-8 W. However, the effect of vacuum degree and particle size distribution on the sample temperature variation is not significant, due to the small order of magnitude of the sublimation heat flow compared to the radiation and conduction heat flows. This paper gives a range of parameters for ground-based simulation experiments and points out the microscopic changes of the ice sublimation process, which provides ideas for the next ground-based experiments and the exploitation of water-ice resources on the Moon.

期刊论文 2023-04-01 DOI: 10.1016/j.actaastro.2023.02.013 ISSN: 0094-5765

Impact gardening is a mixture of excavation by impacts and burial under continuous proximal ejecta. An existing analytical model describes the rate at which impacts excavate material on the Moon (Gault et al., 1974; Costello et al., 2018, ; Costello et al., 2020, ). We expand the model to include a treatment of burial under proximal ejecta. Using the models for excavation and burial, we explore the effects of impacts in the evolution of the lunar surface over the last few billion years. We find that excavation of material by gardening outpaces burial in all reasonable ejecta coverage test scenarios. Thus, gardening does not act as a shield for ice in permanent shadow. However, gardening fails to eradicate the surface expression of compositional contrasts, such as those associated with pyroclastic deposits and compositional rays, which are not vulnerable to removal by thermal or ionization processes. Explorers seeking ice at the lunar poles should not expect regions of permanent shadow to have pure ice within the top 1-10 m because that ice will have been disrupted by gardening.

期刊论文 2021-09-01 DOI: 10.1029/2021JE006933 ISSN: 2169-9097

Published literature suggests that water ice might be unambiguously detected in the presence of background contaminants by developing a frequency swept sensor to obtain the dielectric spectrum. Such a sensor could be incorporated into the tip of a spike and driven into the lunar regolith to detect moisture as a function of depth. A sensor was created to test this concept for varying concentrations of ice in lunar soil simulant under vacuum conditions. Ice relaxation occurs at frequencies well below 1 Hz at temperatures present on the Lunar surface, making it difficult to distinguish ice from the surrounding regolith. So, a heating element was incorporated with the sensor to capture the dielectric spectra as the ice warms, allowing the relaxation to be detected in a shorter period of time. The test results show the ability of this sensor to detect the presence of varying quantities of ice in the soil simulant and the need for more complex non-linear mixing models to quantify the amount of ice present in the mixture. Published by Elsevier Ltd.

期刊论文 2012-05-01 DOI: 10.1016/j.pss.2012.01.010 ISSN: 0032-0633

We have employed the Arecibo Observatory Planetary Radar (AO) transmitter and the Mini-RF radar onboard NASA's Lunar Reconnaissance Orbiter (LRO) as a receiver to collect bistatic data of the lunar surface. In this paper, we demonstrate the ability to form bistatic polarimetric imagery with spatial resolution on the order of 50m, and to create polarimetric maps that could potentially reveal the presence of ice in lunar permanently shadowed craters. We discuss the details of the signal processing techniques that are required to allow these products to be formed.

期刊论文 2012-01-01 DOI: 10.1117/12.923600 ISSN: 0277-786X

The importance of the development of a rover to confirm directly the existence of ice on the lunar polar region is discussed. For a rover working in the shadowed ar ea in the bottom of a crater, a pou er-supply system using a Laser beam from the edge of the crater is proposed. A small system model is fabricated to demonstrate that the system can be realized.

期刊论文 2000-05-01 DOI: 10.2322/tjsass.43.34 ISSN: 0549-3811
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