No full-text available
To read the full-text of this research,
you can request a copy directly from the author.
Lunar Habitats: A Brief Overview of Issues and Concepts
Abstract
A summary of the lunar environment is provided as background to the issues that await resolution by structural engineers who will design habitats for long-term stays on the Moon, initially by pioneering astronauts, and eventually by people who will call the Moon their home. Key environmental concerns are the radiation and micrometeoroid environment, the hard vacuum, and the lack of atmosphere. The lunar dust poses a carcinogenic hazard, as well as an existential threat to engineered systems. Structures need to be designed with an eye to the psychological wellbeing of the inhabitants. This review provides an introduction into some of these aspects of lunar habitat design, and is based on the 2018 book by the author.
... Moon Length of a day 23h 56m [11] 27d 7h 44m [11] Orbit period 365.25 d [12] 655.72 h (around Earth)) [13] Radius (km) 6371 [12] 1737.4) [13] Mass (*10 24 kg) 5.97 [12] 0.073) [13] Gravity (m/s 2 ) Atmospheric pressure at ground level (mbar) Radiation at ground level (mSv/year) 9.798 [12] 1000 [11] 2,4 [14] 1.62 [13] 3*10 -12 [11] 380 [14] ...
... Moon Length of a day 23h 56m [11] 27d 7h 44m [11] Orbit period 365.25 d [12] 655.72 h (around Earth)) [13] Radius (km) 6371 [12] 1737.4) [13] Mass (*10 24 kg) 5.97 [12] 0.073) [13] Gravity (m/s 2 ) Atmospheric pressure at ground level (mbar) Radiation at ground level (mSv/year) 9.798 [12] 1000 [11] 2,4 [14] 1.62 [13] 3*10 -12 [11] 380 [14] ...
... Moon Length of a day 23h 56m [11] 27d 7h 44m [11] Orbit period 365.25 d [12] 655.72 h (around Earth)) [13] Radius (km) 6371 [12] 1737.4) [13] Mass (*10 24 kg) 5.97 [12] 0.073) [13] Gravity (m/s 2 ) Atmospheric pressure at ground level (mbar) Radiation at ground level (mSv/year) 9.798 [12] 1000 [11] 2,4 [14] 1.62 [13] 3*10 -12 [11] 380 [14] ...
The Biodome gridshell system is a proven and lightweight structure developed for the Pannon Park Biodome of the Budapest Zoo. The gridshell system was optimized for loadbearing capacity, while maintaining a homogenous structural system consisting of repeating elements. A Lunar Biodome system can be used for mid-and large-span habitats and analog base structures. The elements of the original Pannon Park Biodome structure were constructed using steel alloy, but they were originally intended to be constructed from aluminum, illustrating the system's flexibility in being adapted to the metallic content available from in-situ extraction. A Lunar Biodome structure can provide shielding for inflatable habitat inserts and also distribute a homogenous load of regolith shielding. The optimal habitat layout sizes and the maximal Lunar Biodome structure size possible are discussed in the paper. Advantages of the system such as applicability for ISRU construction methods and variability of covered floor area, as well as the potential pitfalls and technology gaps such as radiation protection and element casting are discussed.
... Because a lunar lava tube has a hard basalt roof, its internal environmental factors such as temperature changes, radiation doses, and the probability of being hit by meteorites are relatively limited. As such, it offers in theory an ideal human lunar habitat [3,4]. The underground volcanic structures have previously been proposed as ideal sites for human settlements. ...
... The first examples of lunar lava tubes were discovered by a Japanese research team, which analyzes the lunar holes (i.e., skylights) that appeared in the JAXA Kaguya exploration mission data based on their location within a sinuous rill [4]. Since then, evidence of new lava tubes has been discovered continuously [5][6][7]. ...
... Environment. There have been some previous studies about the temperature in lunar lava tubes [4,21]. The average temperatures found at depths of 1.3 m and 2.3 m below the lunar surface of the Apollo 15 and 17 landing sites are − 17°C and − 16°C [6], and temperature also increases with depth [22]. ...
Developing efficient approaches to building a suitable environment for humans on the moon play a key role in future long-term sustainable lunar exploration activities, which has motivated many countries to propose diverse plans to build a lunar base. The lava tubes discovered by the Kaguya mission offer huge potential sites to host such bases. Through computation and analysis, we show that lunar lava tubes offer stable structures, suitable temperatures, low radiation doses, and low meteorite impact rates. We summarize previous research results and put forward the conditions to find and use a suitable lunar lava tube for human habitation on the moon. The establishment of extraterrestrial bases still faces many technical bottlenecks; many countries have begun to use the earth’s environment for extraterrestrial exploration and simulation missions. In this regard, we proposed the idea of using the Earth’s karst caves to simulate extraterrestrial lava tubes, selected caves in Chongqing as the simulation site, and demonstrated the feasibility from both structural and environmental aspects. Finally, we proposed a karst cave simulation platform with three main research directions: cave sealing technology, efficient daylight system, and internal circulation research of artificial ecosystems containing natural soil and rock. We hope to promote the development of related research on extraterrestrial bases through simulation experiments.
... Due to the missing magnetosphere and atmosphere, particles of galactic and solar origin reach the surface of the Moon unattenuated. Any construction on the Moon, including the ones built from regolith, is required to reduce the exposure to safe levels for prolonged human presence on the Moon [34] as well as protect it against meteoroids impacts with velocities that vary from 2.4 km/s to 72 km/s and weighing from less than 1 kg to over 5 tons [35]. When designing the lunar construction, one needs to take into consideration all the abovementioned factors. ...
... The lunar regolith morphology resulted from the continuous impact of meteoroids and the bombardment of the lunar surface by charged particles from the Sun [8]. It has low thermal conductivity, and therefore, the thicker its layer is, the larger the reduction in the temperature variations is [35]. Additionally, from the perspective of radiation health, a regolith layer of 2-3 m thickness provides radiation shielding of about 40 g/cm 2 , whereas Earth's atmosphere provides a shielding equivalent of 100 g/cm 2 . ...
... Additionally, from the perspective of radiation health, a regolith layer of 2-3 m thickness provides radiation shielding of about 40 g/cm 2 , whereas Earth's atmosphere provides a shielding equivalent of 100 g/cm 2 . Rare, large solar flares require shelters with shielding of at least 700 g/cm 2 [35]. By using lunar regolith as an aggregate for mortars or concretes, it is possible to take advantage of those properties and increase the shielding properties of the new construction composites. ...
NASA has revealed that they plan to resume manned missions and ensure the permanent presence of people in the so-called habitats on the Moon by 2024. Moon habitats are expected to be built using local resources-it is planned to use lunar regolith as aggregate in lunar concrete. Lunar concrete design requires a new approach in terms of both the production technology and the operating conditions significantly different from the Earth. Considering that more and more often it is assumed that the water present on the Moon in the form of ice might be used to maintain the base, but also to construct the base structure, the authors decided to investigate slightly more traditional composites than the recently promoted sulfur and polymer composites thermally hardened and cured. Numerous compositions of cement "lunar micro-mortars" and "lunar mortars" were made and tested to study rheological properties, namely, the consistency, which largely depend on the morphology of the fine-grained filler, i.e., regolith. For obvious reasons, the lunar regolith simulant (LRS) was used in place of the original Moon regolith. The used LRS mapped the grain size distribution and morphology of the real lunar regolith. It was created for the purpose of studying the erosive effect of dusty regolith fractions on the moving parts of lunar landers and other mechanical equipment; therefore, it simulated well the behavior of regolith particles in relation to cement paste. The obtained results made it possible to develop preliminary compositions for "lunar mortars" (possible to apply in, e.g., 3D concrete printing) and to prepare, test, and evaluate mortar properties in comparison to traditional quartz mortars (under the conditions of the Earth laboratory).
... It is however, important to notice that all mentioned studies either did not address the issue of energy storage systems (ESS) or assumed nuclear power sources for their lunar facilities. Present strategies for the early stages of manned lunar exploration promote solar-based energy solutions [18,24,25], that require application of energy storage systems. Landis and Bailey [26] presented their estimation of the minimal electric power demand of an initial, solar powered lunar settlement with a biological air revitalization system to be 25 kW. ...
... Landis and Bailey [26] presented their estimation of the minimal electric power demand of an initial, solar powered lunar settlement with a biological air revitalization system to be 25 kW. The most recent works [24,25,27] recognise the importance of the IHG issue in lunar settlements, but does not address it in detail. Numerous works [15][16][17]26] point out the necessity for a more custom approach to lunar bases heat gains, to be done by addressing their individual architectures, contemporary technologies and mission profiles. ...
... The purpose of this paper was to assess the total value of internal heat gains of a future lunar base of the same architecture and function assimilated in the LUNARES habitat during the ICAres-1 mission. It was accomplished by revisiting the actual inventory of LUNARES [28], adjusting and supplementing it to mirror a complete inventory of a lunar scientific facility according to contemporary baselines for space station subsystems [13,24,25]. State-of-the-art electric devices were assumed to be used aboard the base. ...
The Moon’s environmental conditions present limited opportunities for waste heat dissipation, so internal heat gains (IHG) are a key component of thermal balance in a lunar building. Despite the significant development in energy saving and energy storage technologies of the last thirty years, the issue of IHG in lunar buildings has not been readdressed since the early 1990s. This study is based on an inspection of internal heat sources conducted aboard LUNARES, the first European extraterrestrial analogue habitat. The equipment absent on LUNARES, but indispensable for an actual lunar base, was identified and accounted for, along with additional laboratory and maintenance equipment. Three main groups of internal heat sources were identified and studied in detail. Waste heat generated by electric devices was accounted for, along with occupational heat loads adjusted for lunar partial gravity conditions. Assuming a photovoltaic power source for the studied building, two alternative energy storage systems (ESS) were analysed as another source of waste heat. Depending on the time of lunar day and applied ESS, the nominal IHG were between 73 and 133 W/m2. The most significant internal heat sources in a lunar base are life support systems and potentially, regenerative fuel cells; thus, lithium–ion batteries were recommended for ESS. Within assumed parameter range, parametric study exhibited differences in IHG between 41.5 and 163 W/m2.
... The Moon, being the Earth's nearest planetary neighbor, has been understood better because several manned and unmanned missions have been carried out on it by different space agencies. Therefore, the Moon has a high potential for near future novel scientific advances and possibilities [2]. National Aeronautical and Space Administration (NASA) carried out several Apollo human missions to the Moon during 1960s and 1970s, and has been exploring the possibility of establishing long-term human habitation there [3]. ...
... Fig. 4 provides a representative portion of the two-dimensional view of a vertical plane passing through the middle of the structure. In the external wall surface, the nodes are subjected to outer wall boundary condition in the form of flux as provided in Eq. (2). Solar radiation, nonblackbody radiation, and habitat albedo input are subjected to the habitat external wall surface in the form of flux. ...
This paper presents the methodology to determine the temperature profile at the surface and through the wall
thickness of a monolithic hemispherical dome-shaped habitat structure built on the lunar surface. The three dimensional
thermodynamic equation of heat diffusion is used to determine the temperature profiles using the explicit finite difference scheme. The direct solar radiation and lunar albedo are taken as the heat sources on the habitat structure whereas non-black body radiation and habitat albedo were taken as heat sinks. In this study,
all the applicable modes of heat transfer – radiation in the external wall surface, convection in the internal wall surface (interior habitat will have air for human missions), and conduction in the structural wall body – have been considered. This temperature analysis study also takes into consideration of the self-shadowing effect of the habitat structure itself. The temperatures at the surface and through the wall thickness of the monolithic dome habitat structure were determined for the habitat structure made of sintered lunar regolith simulant, and for the purpose of comparison, regular terrestrial concrete, for three complete lunar day-and-night cycles. While the maximum temperature of around 390 K was observed at the apex of the sintered lunar regolith simulant dome during the lunar noon, the minimum temperature observed was around 213.5 K during the night time on the external surface of the habitat wall. The corresponding results for the lunar habitat structure made of terrestrial concrete were 364 K and 222.5 K, respectively. At the inner surface of the 40 cm thick habitat structure (in contact with interior habitat environment), the temperature fluctuation (difference between maximum and minimum temperatures) can be up to 30 K for each material type. The results from this study should help to determine the structural stresses and deflections caused by such lunar environment temperature fluctuations and
the heat regulation for habitability in the future habitat structure on the Moon. Moreover, the methodology presented in this study should be applicable to conduct parametric studies to evaluate the effect of different parameters on the structural habitat temperature results.
(https://doi.org/10.1016/j.actaastro.2022.12.040 )
... Habitation: Harmful levels of solar radiation and extreme day-night temperatures exist on the lunar surface. Habitat designs may utilise lunar regolith as shielding through burying or installing habitats underground [2,3]. Essential services or connections between habitats and other facilities may also require burial for radiation shielding, thermal stability or to remove congestion similar to plumbing, gas, electricity and telecommunications lines on Earth [4]. ...
... The samples are created and checked to ensure that the simulated porosity is close to the calculated porosity shown in Table 1. The modelled empirical equation for the density of the lunar soil based on observations made by Carrier, Olhoeft and Mendell [31] is shown in Equation (2). This is transcribed into Table 1 for each respective depth (m). ...
Applications of tunnels on Earth range from exploration, exploitation, transportation, infrastructure to human habitation. Similarly with the increased focus on habitation on the Moon, tunnels will be required to support these operations. Geomechanical properties are key factors to successfully drill a tunnel. These properties along with excavation dimensions must be appropriate for the tunnel's stability.
The research outlined in this paper aims to determine the stability of small diameter horizontal tunnels in lunar regolith and conditions using the capability of the Discrete Element Method (DEM). The YADE DEM program was used for the numerical analysis in this paper. Lunar regolith data from various published papers and simulated triaxial testing has been used for model calibration. Results yield a tunnel stability chart showing size and stability increases with sample compaction and decreases with an increase in tunnel diameter. Seismicity tests also show that low level vibrations destabilise the tunnel with ease.
... It is unclear whether Japan is still planning to build a Lunar base, announced in 2005, by 2030 or whether it allocated a budget for the program [22]. In-Situ Resource Utilization (ISRU) for the construction of these outposts would be crucial to space sustainability [23], as it would reduce the mass, volume, DeltaV budgets, and mission costs by 3-4 orders of magnitude and instead rely on utilizing the lunar regolith and using local materials with additive manufacturing technologies to build the necessary infrastructure on the Moon, making the Moon the starting point for future launches into space [24]. In addition, the lunar regolith contains silicon, Aluminum, Titanium, Nickel, Helium-3, and water, which can be utilized to sustain lunar crews living in lunar settlements, manufacture space hardware, grow hydroponic crops inside lunar green habs, produce rocket propellant and solar or nuclear power through solar panels, small nuclear fission reactors, Radio-isotope Thermal Generators (RTGs), or fuel cells [23,25]. ...
... In-Situ Resource Utilization (ISRU) for the construction of these outposts would be crucial to space sustainability [23], as it would reduce the mass, volume, DeltaV budgets, and mission costs by 3-4 orders of magnitude and instead rely on utilizing the lunar regolith and using local materials with additive manufacturing technologies to build the necessary infrastructure on the Moon, making the Moon the starting point for future launches into space [24]. In addition, the lunar regolith contains silicon, Aluminum, Titanium, Nickel, Helium-3, and water, which can be utilized to sustain lunar crews living in lunar settlements, manufacture space hardware, grow hydroponic crops inside lunar green habs, produce rocket propellant and solar or nuclear power through solar panels, small nuclear fission reactors, Radio-isotope Thermal Generators (RTGs), or fuel cells [23,25]. ...
Humanity is returning back to the Moon to establish a permanent and sustainable human-robotic presence on the lunar surface before the end of the decade. In addition to orbiters, landers, rovers, and crews, some nations aim to contribute to a more sophisticated and sustainable lunar architecture by building lunar bases. In this regard, The Moon Village Association is the only global organization that provides a platform and takes actions supporting communications and cooperation among all elements of the human society supporting the Moon Village concept, including both space-faring and non-space-faring countries and offers them the opportunity to play a role in its realization. Over the past decade, Egypt has been making constitutional amendments to officially establish a national space agency and position space exploration as an integral part of Egyptian society. In 2019, Egypt officially established the Egyptian Space Agency (EgSA) and drafted a high-level national space strategy for 2030, one of which is to explore deep space. Egypt's participation in the Moon Village Association (MVA) Participation of Emerging Space Countries (PESC) project complements these national efforts and interests to set more Specific, Measurable, Attainable, Relevant, and Timed goals and feasible milestones for its short-term, mid-term, and long-term objectives from a project management perspective. This is all a reflection of Egypt's enthusiastic youth, positioning the nation as one of the leading emerging space countries to develop a domestically-built spacecraft to embark on the first Egyptian deep-space mission orbiting the Moon. In this paper, the MVA-Egypt founding team focuses on highlighting Egypt's interests and capabilities by identifying the commercial, scientific, and technological gaps in the past as well as in the active and planned lunar missions and highlighting opportunities for Egypt and the scientific community. We present Egypt's lunar exploration roadmap and investigate the current potential opportunities in the industry. To assess the gaps and opportunities, we tabulated the previous, ongoing, and planned lunar orbiter missions based on several data points, such as mission, country/operator, launch date, cost, launch mass, Launch Vehicle (LV), lunar delivery Space Transportation System (STS), orbit, landing site, main objectives, main instruments, and resolutions.
... Benaroya has overviewed key issues and concepts relative to habitat design within the harsh lunar environment, and surveyed examples of Class I, Class II and combinations therein within prior research. [20] Multiple options have been considered relative to locating a habitat on the lunar surface-above the surface and shielded by regolith, inside lava tubes, or partially excavated within the ground plane. [21] Concepts for packed, modular regolith components were investigated and expanded on from a study conducted by Kaplicky, Nixon, and Wernick. ...
... hardshell structure ( Figure 22) was adopted from Bodkin et al. [9] Habitat geometry for the inflatable structure ( Figure 23) was adopted from habitable soft-goods inflatable studies by NASA. [23] Within the so-called bucket scheme, a 3D-printed shell is printed in-place through one of two methods: construction with a capstone at the roof of a dome structure, or construction of an unenclosed vault using sectional "slices" that are printed horizontally and tilted up to a vertical orientation (see Figures 19,20). ...
In Project Olympus, ICON and SEArch+ have developed design schematics for critical surface infrastructure necessary for a permanent lunar base. In 2020 ICON was awarded an SBIR contribution from Marshall Space Flight Center (MSFC) to contribute to NASA Marshall's Moon-to-Mars Planetary Autonomous Construction Technologies (MMPACT) initiative. ICON will first demonstrate additive manufacturing capabilities for horizontal structures such as roads and landing pads, followed by demonstrations of vertical structures, including unpressurized radiation shelters as well as habitats. In 2020, ICON employed SEArch+ to develop design schematics for mission-critical surface construction elements for a lunar settlement, including concepts for surface-site deployment, construction sequencing, and structural design. The design process was informed by discussions with key ICON engineers and NASA collaborators. The exchange not only ensured the constructibility of designs according to hardware and material processing limitations, but also enabled the architectural process to influence and shape hardware requirements as they were being defined. The ensuing habitat design, titled the "Lunar Lantern" for its double-protective outer shield structure, celebrates and promotes a design approach driven by human factors principles to ensure the safety and security of future crew. As a whole, Project Olympus envisions the construction of durable, self-maintaining, and resilient surface structures enabled by advanced 3D-printing technologies. Nomenclature 3D = 3-dimensional 3DP = 3D-printed ConOps = concept of operations ECLSS = environmental control and life support system ISRU = in-situ resource utilization LRO = Lunar Reconnaissance Orbiter MMOD = Micrometeoroid & Orbital Debris MMPACT = Moon to Mars Planetary Autonomous Construction Technologies MSFC = Marshall Space Flight Center PSR = permanently shadowed region RLSO2 = Robotic Lunar Surface Operations 2 1 Co-Founder, Project Associate, SEArch+. Current
... These solutions are reliable and able to work continuously for years, regardless of environmental conditions. In particular, space-rated, compact nuclear reactors are not dependent on the availability of solar radiation and thus are able to continuously supply power to a lunar base without a need for a massive, highcapacity energy storage system (ESS) [27,[33][34][35][36]. Nonetheless, when using a nuclear reactor to power a manned lunar base, the issue of radiation protection must be addressed. ...
... The best available solution for ESS with sufficient technological readiness are Lithium-ion (Li-ion) batteries. Li-ion batteries have very high round trip efficiency and more than ten years of successful space application history, which is more than sufficient to consider this technology adequate to use onboard a lunar base [27,34,41]. The most important issue with Li-ion batteries as a high-capacity ESS is their unsatisfactory specific energy (gravimetric energy density, eS) [42]. ...
Due to the extreme cost of cargo transportation from Earth to the lunar surface, future lunar base subsystems are required to be rigorously optimized in terms of mass reduction. The purpose of this paper was to identify and evaluate the influence of key parameters of proposed lunar base power systems, as well as of the lunar environment on the total power system mass. Nine different power systems were studied as combinations of two power sources and three energy storage technologies. Power system architecture, total power demand of the base, its power management strategy, solar array structure type, Selenographic latitude and solar illumination conditions were nominated as the primary parameters for this study. Total power system mass calculations were performed for more than 200 combinations of these parameters, including three separate case studies. The total mass calculated for each combination included a power source, an energy storage unit, temperature control and the balance of system. For the wide range of studied parameters, hybrid power systems that combine solar and nuclear power were found to be the most advantageous solutions in terms of mass reduction.
... The bulk of the meteoroids is in the 30-150 µm size range and consists of particles with an individual mass of 10 −10 -10 −8 kg, which impact the surface at velocities of~10-72 km/s, thus causing a mass of 10 3 -10 6 times the impact mass to be ejected, depending on the substrate. Since the ejecta particles are smaller than the impactor, this Biomedicines 2023, 11,1921 3 of 21 results in the very fine component of the lunar regolith being generated [13]. Furthermore, these secondary particles get launched at high speed and can contribute to the formation of dust clouds around the moon, or even escape the lunar environment entirely if their speed is >2.4 km/s [14]. ...
The lunar dust problem was first formulated in 1969 with NASA’s first successful mission to land a human being on the surface of the Moon. Subsequent Apollo missions failed to keep the dust at bay, so exposure to the dust was unavoidable. In 1972, Harrison Schmitt suffered a brief sneezing attack, red eyes, an itchy throat, and congested sinuses in response to lunar dust. Some additional Apollo astronauts also reported allergy-like symptoms after tracking dust into the lunar module. Immediately following the Apollo missions, research into the toxic effects of lunar dust on the respiratory system gained a lot of interest. Moreover, researchers believed other organ systems might be at risk, including the skin and cornea. Secondary effects could translocate to the cardiovascular system, the immune system, and the brain. With current intentions to return humans to the moon and establish a semi-permanent presence on or near the moon’s surface, integrated, end-to-end dust mitigation strategies are needed to enable sustainable lunar presence and architecture. The characteristics and formation of Martian dust are different from lunar dust, but advances in the research of lunar dust toxicity, mitigation, and protection strategies can prove strategic for future operations on Mars.
... The moon is the earth's nearest planetary neighbor and scientists are exploring for the options of scientific advancement and possibilities there (Benaroya 2017). National Aeronautical and Space Administration (NASA) has been conducting human missions to the moon and has been exploring the long-term human habitation (Schmitt, 2007). ...
... The moon is the earth's nearest planetary neighbor and scientists are exploring for the options of scientific advancement and possibilities there (Benaroya 2017). National Aeronautical and Space Administration (NASA) has been conducting human missions to the moon and has been exploring the long-term human habitation (Schmitt, 2007). ...
This paper presents the surface temperature and temperature through thickness profile of a monolithic concrete dome habitat structure in the intact and damaged condition on the Moon. Due to long duration days and nights in the lunar environment, a habitat built on the Moon is subjected to extreme temperature fluctuations. The three-dimensional thermodynamics heat balance equation was solved using the explicit finite difference method. While the direct solar radiation and lunar albedo were used as the heat sources, non-blackbody radiation and habitat albedo were taken as heat sinks. The convective boundary condition with the constant interior air temperature of 293.15 K was used for the temperature calculation. In the intact condition, the maximum temperature of around 365 K was found at the external wall surface on crown (apex) of dome during the solar noon and the minimum temperature of around 222 K was determined during the night time irrespective of the location on the dome. For the damaged condition, the difference between daytime high and nighttime low temperature at the interior wall surface of the lunar structure can be as large as 57 K.
... The overview of rigid and inflatable structures has shown that they still face some problems [29]. ...
Recently, demands for space habitats have increased significantly with the growth of space applications for micro-gravity investigation and space travel. Therefore, there is an urgent need for feasible and practical space habitats to satisfy humanity's growing demands for deep space exploration. This paper and its companion paper propose a deployable composite cabin (DCC) and present a comprehensive study on the folding behaviour of the DCC. Part 1 provides the conceptual design of the DCC and verifies the effectiveness and feasibility of the DCC through the experimental method and numerical simulation. The DCC can achieve folding and deployment functions through elastic deformation in the large deformation process. Using T300/epoxy unidirectional reinforced prepreg as raw material, DCC specimens were prepared by the autoclave moulding process. The experimental fixture was designed and the large deformation folding function of the DCC was successfully verified. The load-displacement curves with typical three stages were obtained. In addition, based on the Riks method and the static method, a finite element analysis (FEA) model was established to predict the folding behaviour of the DCC. The geometric nonlinearity and initial imperfection were considered in the FEA model. The numerical simulation results were in good agreement with the experimental results.
... Furthermore, the temperature changes rapidly which must be considered because of the thermal expansion and contraction of materials. In addition to this, the radiation of the sun is more intense than on Earth and is not only a big danger for humans but can also lead to damage of electronic components [7]. On the moon, the duration of a day cycle is about 29.5 Earth days which means lunar day and lunar night both are about 15 earth days long [8]. ...
To enable a long-term presence of humans in space, it is essential to use extraterrestrial raw materials to reduce the need for transporting resources or produced materials from Earth. In recent years, a lot of research has been conducted on different ISRU processes, such as regolith excavation, mineral processing and the extraction of oxygen using metallurgical processes. However, it is not sufficient to just focus on a single process but also to focus on how the different processes interact. Therefore, RWTH Aachen’s Integrated Conceptual Design presents a novel concept for the production of oxygen and high-quality metal materials. To meet the challenges of mining in space, selective mining is used to provide the best possible blend based on the original material of the deposit. This process is followed by mineral processing to provide a high-quality ilmenite-rich concentrate, the input material for metallurgical processes. Using the novel MOSARI technique, consisting of molten salt electrolysis and metallothermic reduction, oxygen and metal materials can be recovered. Furthermore, this represents a zero-waste approach for the complete utilization of the material.
... On the other hand, some of the most critical lunar hazards (Benaroya, 2017;Kalapodis et al, 2020) will be i) the radiation generated by galactic cosmic rays or solar energetic particles that may pose a threat to the subsystems of the Lunar structures (e.g., a deployable system) ii) the lack of atmosphere, which results in frequent meteoroid impacts and showers iii) the Moon's high temperature fluctuations and last but not least, the most crucial factor affecting the future OES's stability is iv) the partial gravity. The effect of partial gravity on various fundamental dynamic systems is thoroughly investigated by Kalapodis et al, (2019). ...
Following the current trend towards the space exploration, this study focuses mainly on the conceptualisation of the most efficient lunar arch forms to be adopted by the future structural designers. More specifically, the static behaviour of varying-thickness arches (VTAs) produced by an iterative form-finding algorithm against constant-thickness arches (CTAs) is examined herein. These optimised arches are assumed to be constructed by laser-sintered additive manufactured lunar regolith, following a 3D-printing technique. The paper initiates with finite element analysis (FEA) of both VTAs and CTAs where it is witnessed that VTAs need to be geometrically enhanced, by means of thickening certain weak/narrow parts of their cross-section, in order to minimise the principal compressive and tensile stresses and the amount of strain energy exhibited locally. The work concludes with the quantification of the efficiency of the enhanced VTA shapes over the typical CTAs in lunar gravitational environments.
... All countries are conducting lunar exploration research with the hope of building a survivable lunar station (Reitz et al. 2021;Fateri et al. 2019). However, many technological challenges such as the survival ability of the equipment arise during the planning for a robotic or manned lunar mission fully operational during the lunar night (Benaroya 2017;Fraser 2012;Palos et al. 2020). In past attempts at lunar exploration, many technologies have been used in thermal control systems, such as multiple insulation layers (Kim 2020;Plachta et al. 2012), single-phase, two-phase (Simonsen et al. 1992), and heat pumps (Sridhar and Gottmann 1996). ...
The structural design, heat transfer capability analysis, ground equivalent validation, and on-orbit flight of the two-phase fluid loop based on flat-plate evaporation module of the Chang’e-4 detector are introduced. Within the temperature range of -30 ℃ ~ -10 ℃, the designed two-phase fluid loop has a heat transfer capacity of greater than 200 W. An equivalent test prototype is designed and manufactured to examine the heat transfer performance of the two-phase fluid loop under the ground condition of 1 g. The driving force of the equivalent test prototype is less than that of the flight prototype, while the flow resistance is equivalent to that of the flight prototype. The test heat transfer capacity is smaller than that of the flight prototype on the lunar surface. According to the equivalent test prototype, the heat transfer capacity is no less than 130 W, which meets the requirements of Chang’e-4. During the 14-moon day-night cycle, the temperature of the two-phase fluid loop gradually decreased to an equilibrium value of -10 °C. During the wake-up process of the detector in moon day, the control valve was closed, and the temperature of the flat-plate evaporation module rose rapidly, indicating that the function of blocking heat transfer is normal.
... These facilities must be able to remain resilient against extraterrestrial hazards [16,20]: i) radiation generated by either galactic cosmic rays or solar energetic particles that can pose a great threat to the subsystems of any Lunar structure (e.g., a deployable system), ii) the lack of atmosphere which is responsible for the frequent meteoroid impacts and meteoroid showers, iii) the high temperature fluctuations (up to 280 K or o C) on the Moon's surface, iv) ground motions generated by different types of Moonquakes. Finally, one of the most dominant factors that will affect the stability of the future OES is partial gravity. ...
Following the current trend towards the lunar exploration and habitation, this study focuses on the development of efficient arch forms to be adopted for future long-span shielding structures on the lunar surface. More specifically, the static behaviour of the optimised, varying-thickness arches (VTAs), produced by a previously proposed iterative form-finding algorithm based on limit thrust-line analysis under gravitational and seismic loading is examined herein. These form-found arches are assumed to be constructed by laser-sintered additive manufactured lunar regolith. This paper starts with the visualisation of the limit thrust line using finite element analysis (FEA) on constant-thickness arches (CTAs). Subsequently, it presents the results from FEA on both VTAs and CTAs where it is observed that the original VTAs need to be geometrically enhanced, by thickening certain weak areas of their cross-section in order to minimise the local principal stresses and strain energy. The work proceeds with the quantification of the efficiency of the enhanced VTAs against their CTA counterparts, in both terrestrial and lunar gravitational environments. The most efficient enhanced VTAs are selected and recognised as the best structural forms for either terrestrial or lunar applications among all the arches examined in this research. Eventually, the real capacity of those most efficient arches against lateral loading is attested by means of pushover analysis. As expected, it is found that the geometric enhancement has significantly increased their structural capacity.
... Charged microparticles on the Moon have increased adhesion ability, which introduces various limitations to the use of space systems on its surface, from the contamination of the surface of solar panels to the decreased operational life of the details of rubbing mechanisms [8,9]. This is why it is currently important to obtain flows and levitating clouds of charged dust similar to lunar dust under laboratory conditions [10][11][12][13][14] to conduct simulation experiments and testing of both materials and components of future space technology, including lunar habitats [15,16]. Such experiments are conducted using acceleration technology [17][18][19][20], electron beams [12][13][14] or electrostatic powder dispensers [21]. ...
In this article, results are presented of experiments on depositing charged particles, which imitate the levitating dust on the Moon, on stainless steel. Ensembles of particles are created above the surface of laboratory regolith whose composition and particle size distribution imitate the dust that covers the Moon's surface. Under the action of the gyrotron radiation on regolith, non-linear physical-chemical processes develop (breakdown, chain plasmachemical reactions, and particle scattering by the Coulomb mechanism), which lead to the appearance of a levitating cloud of particles. The simulation experiment is based on the similarity between the processes that develop in the laboratory experiments with regolith and the processes that occur on the Moon during its bombardment by micrometeorites. The effect of the levitating cloud on stainless steel plates is studied and it is shown that regolith particles in the shape of spheroids of different sizes are deposited on the surface of the plates. The dimensions of the deposited particles and the density of their placement depend on the quality of treatment of the plate surface. It is shown that the laboratory-produced dusty plasma can be used in simulation experiments to study the modification of surfaces of different materials for space technology.
... They contemplated developing the surface outposts to shelter the astronauts from space radiations, meteorite collisions and extreme temperature fluctuations. Detailed descriptions of such environmentally harsh conditions can be found in [3][4][5]. So far, plenty of different layouts of outposts have been conceptualized by construction professionals and civil engineers [6][7][8][9][10][11][12][13][14][15][16]; however, the description of their details is out of the scope of this article. ...
From the 2000s onwards, unprecedented space missions have brought about a wealth of novel investigations on the different aspects of space geomechanics. Such aspects are related to the exploratory activities such as drilling, sampling, coring, water extraction, anchoring, etc. So far, a whole range of constitutive research projects on the plate tectonics, morphology, volcanic activities and volatile content of planetary bodies have been implemented. Furthermore, various laboratory experiments on extraterrestrial samples and their artificial terrestrial simulants are continually conducted to obtain the physical and mechanical properties of the corresponding specimens. Today, with the space boom being steered by diverse space agencies, the incorporation of geomechanics into space exploration appreciably appears much needed. The primary objective of this article is to collate and integrate the up-to-date investigations related to the geomechanical applications in space technologies. Emphasis is given to the new and future applications such as planetary drilling and water extraction. The main impetus is to provide a comprehensive reference for geoscience scientists and astronauts to quickly become acquainted with the cutting-edge advancements in the area of space geomechanics. Moreover, this research study also elaborates on the operational constraints in space geomechanics which necessitate further scientific investigations.
... Potential residents could be tourists, scientists, or Lunar resources miners. An overview of issues and concepts of Lunar habitats is provided by Benaroya [18]. ...
Building up on previous market studies for the aviation industry, the terrestrial tourism industry, the sub-orbital tourism market, and the orbital tourism market, we conduct qualitative and quantitative market surveys to estimate the size and value of the Lunar Tourism market. Based on initial assumptions, the target customers are expected to be 25 year old and beyond, pioneering individuals that belong to the innovator and early adopter groups of this lunar hotel's product lifecycle, and would psychographically have travel-based exploration and a fascination for science-fiction ingrained in their personalities. They would typically have a strong inclination towards adventure sports and expeditionary traveling. These consumers tend to have similar social circles and utilizing the emotion of fear of missing out (FOMO) is likely to play a vital role in customer acquisition. Lunar Tourism is initially set to be marketed as very niche expeditions meant to be the highlight of a person's lifetime. Though the Lunar hotel would be more likely to attract wealthy tourists in its initial phases of development, the evolution of the space tourism market would be highly dependent on the development of low-cost launch services that would make the access to space affordable to the general public. In the meantime, a new market would have to be created for a niche customer group with high standards, which might not directly influence the democratization of space in the relatively short term but would be essential for the creation of an initial market and the development of the Lunar business ecosystem. As the demand increases, the competition among different stakeholders will increase and new, more diverse services for different niche market segments will be created. This survey should uncover insights on the demographic and psychographic characteristics of the target customers, the perceived value of Lunar Tourism from the perspective of the customers, and the demands and requirements of the customers, which would affect the design of the hotel and the types of services offered.
... Moreover, the lunar dust can cause a carcinogenic hazard, as well as an existential threat to any extraterrestrial system. Therefore, structures and systems on the Moon need to be designed with the psychological well-being of the inhabitants 3,4 . ...
View Video Presentation: https://doi.org/10.2514/6.2021-3160.vid One of the major consequences of climate change will eventually be housing. A solution to the looming housing crisis is space colonies. Due to limited resources, space colonies would require energy-efficient housing. Looking at nature, we can be inspired to engineer new technologies that address modern problems. Penguins breed in extreme conditions with low energy expenditure using coloration, a layered feather system, and huddling. Thermal imaging of penguins was conducted to model heat transfer effects due to coloration. In addition, heat transfer from huddling was modeled using COMSOL Multiphysics in a variety of geometries to test the effectiveness of huddling. By expanding upon this project, a highly efficient structure designed for space exploration can be created in the future.
... -Severe lunar day-night temperature cycling (+127ºC to -173ºC) 6 , and high temperature gradients during the transition from daylight to nighttime (about 5°C/h). ...
Using space-based resources (In-Situ Resource Utilization, ISRU) to produce life support and propulsion consumables such as oxygen or water offers the possibility of a more sustainable and cost-effective exploration of the Moon when compared to missions relying solely on material transport from Earth. Learning how to operate on the Moon with local resources, reduced gravity, and a harsh environment is a stepping stone towards developing technology for a sustained human presence in space. We analyze several technical concepts to produce oxygen or water from lunar regolith. Thermochemical reduction processes of solid lunar materials using hydrogen (hydrogen reduction of ilmenite), methane (carbothermal) reduction and other processes such as molten salt electrolysis (e.g. the FFC-Cambridge process) are evaluated. Focus is set on the technological solutions for supporting fluid management systems required to produce, separate, collect, and measure water or oxygen from solid oxide chemical/electrochemical processes, evaluating their technology readiness level, current necessary developments and their potential interaction with other life support International Conference on Environmental Systems 2 and exploration activities. Technology de-risking plans to demonstrate fluid management system feasibility and tests in relevant environments are proposed to support establishing a human presence on the Moon sustained by local resources. Nomenclature ACD = Anode-to-cathode distance EOP = Electrochemical Oxygen Pump ESA = European Space Agency FFC = Fray, Farthing, Chen-Cambridge Process FMS = Fluid Management System GCR = Galactic Cosmic Rays IL = Ionic Liquids ISRU = In-situ Resource Utilization LEO = Lower Earth Orbit PSS = Process Subsystem (PSS) RAS = Regolith Acquisition System RTS = Regolith Transportation System TRL = Technology Readiness Level
... However, it is evident that the autonomous systems resident on the lunar base will need to function in concert and be optimized for safety [2]. Additionally, the autonomous systems will be subject to extremely harsh operating conditions given constant exposure to radiation, micrometeorites, lunar dust and other hazards [4]. The autonomous systems that enable the operations of the Artemis Base Camp should ideally be supported by its surrounding infrastructure to achieve its mission objectives. ...
Space habitats such as NASA’s proposed Artemis Base Camp will house both astronauts and autonomous systems. The Artemis Base Camp’s infrastructure could provide supporting services to its tenants to optimize their function. This calls for a smart city ecosystem. Maslow’s Hierarchy of Needs has been engaged as a framework to inform human-centric smart city design and feature prioritization; however, autonomous systems have different needs to humans. This paper aligns the needs of humans and autonomous systems in a framework called Autonomy’s Hierarchy of Needs, which provides a smart city ecosystem design framework for the Artemis Base Camp.
... Within the literature, there is a good understanding of the principal types of in-situ resource utilisation (ISRU) products that will be needed at a sustainable lunar outpost; oxygen [2][3][4], water [5][6][7], shelter from radiation, regolith dust, and micrometeorites [8][9][10][11][12][13][14][15][16][17]. However, within the literature, there is significant technological uncertainty regarding how lunar resources will be utilised by missions to yield those principal products. ...
The purpose of this study was to deploy a Delphi expert elicitation methodology to better understand the technical and policy challenges facing the development of a sustainable lunar outpost in 2040, including the types and scale of ISRU deployment. We used a three-round Delphi survey with an open first round and specific questions in later rounds using a four-point Likert scale and two ranking exercises to assess energy technologies and inhibiting factors. In order to provide more certainty to our potential participants regarding their input, and boost engagement, the study deployed a three-round approach that was communicated to our potential participants and decided ex-ante. Potential participants were identified from the literature and academic networks as those who had made significant contributions to the fields of; ISRU technologies, space architecture, space-qualified power systems, and space exploration. The study identified around 20 major themes of interest for researchers in the first round and asked participants to rate their agreement with a number of statements about a hypothetical lunar outpost in 2040. From the group responses, we identified three major technical challenges for the development of a lunar outpost in 2040; developing high power energy infrastructure, lander and vehicle ascent capacity, and mission architectures and technical approaches. We also identified three major policy challenges for the development of a lunar outpost in 2040; US and global political instability, possibility of an extended timeframe for the first lunar landing, and political distaste for nuclear energy in space. The group was uncertain about the precise energy mix at the outpost as a result of uncertainty regarding electrical loads, but there was general agreement that solar PV would be a significant contributor. Whether nuclear power sources might play a useful role proved to be very uncertain, with some participants noting a political distaste for space nuclear power systems. However, the proposition gained two votes in each ranking position, suggesting it has a flat distribution including both supporters and detractors.
... The lunar soil was never exposed to erosion factors like wind and rain, leading to an irregular, angular shape with sharp edges of the regolith particles [26], often incorporating fused glassy inclusions. Particles with such shapes are very abrasive and can easily damage moving parts of processing equipment [27]. Small sharp particles are highly toxic -they can be cancerogenic if inhaled [28,29]. ...
This review discusses the development prospects of additive technologies for the manufacturing of complex technological items on the surface of the Moon under scarce resource availability and low-gravity conditions. One of the expected materials for 3D printing as part of a prospective lunar research program is the lunar regolith. It is easily accessible on the Moon in a few forms, depending on geographical location. Due to the limited availability of the lunar regolith on Earth, several attempts to use geological simulants of the regolith were made by research groups worldwide to analyze the applicability of additive manufacturing (AM) technologies for lunar 3D printing. The present review is aimed at discussing recent achievements in the development of chemical and technological aspects of 3D-printing technology for the use of the lunar regolith. A detailed description of all known AM approaches is presented, and the results obtained by various research groups are compared and discussed.
All available experiments with 3D printing for in-situ fabrication with lunar regolith were analyzed, systematized, and generalized. Finally, we have formulated the basic requirements and approaches for adapting additive manufacturing methods to lunar surface conditions.
... Among aramid fibers, Vectran [71] was selected for the construction of high-strength fabrics of the inflatable plug. Vectran is commonly used in aerospace applications where high-strength, high foldability with minimum degradation is required [72][73][74][75][76][77][78][79][80][81][82][83]. Tests at coupon level included tensile testing, friction testing under dry and wet conditions, crease fold testing, long-term static loading on single and seam specimens, abrasion testing, and flammability of coated specimens. ...
The protection of underground civil infrastructure continues to be a high priority for transportation and transit security agencies. In particular, rail transit tunnels running under bodies of water are susceptible to disruptions due to flooding caused by extraordinary climatic events such as hurricanes or other events resulting from human activities. Several events have taken place in the past decades that have demonstrated the need to mitigate vulnerabilities or, at least, minimize the consequences of catastrophic events. Although it is impossible to prevent all situations that can lead to flooding, damage can be substantially decreased by reducing the area affected by the event. To minimize the effects of an event, a possible approach is to compartmentalize the tunnel system by creating temporary barriers that can contain the propagation of flooding until a more permanent solution can be implemented. One way to create a temporary barrier is by the deployment of a large-scale inflatable structure, also known as an inflatable plug. In such an application, the inflatable structure is prepared for placement, either permanently or temporally, and maintained ready for deployment, inflation, and pressurization when needed. The internal plug pressure imparts a normal force against the tunnel wall surface with the friction between the plug and tunnel surfaces opposing axial movement of the plug. The sealing effectiveness depends on the ability of the inflatable structure to self-deploy and fit, without human intervention, to the intricacies of the perimeter of the conduit being sealed. Primary design constraints include having the plug stowed away from the dynamic envelope of the trains and being able to withhold the pressure of the flooding water. This work presents a compilation of the main aspects of the activities completed for the development of large-scale inflatable structures as part of the Resilient Tunnel Plug (RTP) Project. The main test results and lessons learned are presented to demonstrate the viability of implementing large-scale inflatable plugs for the containment of flooding in rail tunnels systems. Over 400 coupon and specimen tests, 200 reduced scale tests, and 100 full-scale tests were conducted to demonstrate the efficacy of the design of different prototypes over a 10-year research and development project. The culmination of the work was 12 large-scale flooding demonstrations where the inflatable tunnel plug was shown able to be deployed remotely and withstand a simulated flooding event.
Journal of Infrastructure Preservation and Resilience, 1(11):1-28. https://doi.org/10.1186/s43065-020-00011-0
The development of small subterranean deployable structures provides a novel methodology for thermal insulation and radiation protection of scientific payloads for future lunar missions. This work showcases the fabrication and characterization of an origami-inspired self-deploying dome fabricated from amorphous metal foil, taking advantage of the high elastic strain limit of amorphous metals to store energy for deployment in the foil folds when the structure is in the stored configuration. Experiments are performed to understand the influence of material selection on stored energy and springback. A cylindrical structure is fabricated to develop a simulation model for origami-inspired amorphous metal structures and probe the structural integrity of amorphous metal foil structures during repeated loading cycles. Finally, a prototype deployable dome structure is manufactured to showcase the self-deployment strategy and investigate deformation under a simulated lunar regolith load.
When a cubic lattice packaged by a boundary layer is subjected to a mechanical and temperature load, the force and length change of the bonds are equivalently evaluated by the average stress and strain of the unit cell. Provided a displacement gradient variation at a certain stress state, the variation of stress related to the strain variation provides the effective stiffness of the material at the corresponding configuration. It is discovered that the effective elasticity and thermal expansion coefficient can be tailored by the prestress through the boundary layer, which generates a configurational stress. Because the bonds of a cubic lattice depend on the material types, we consider the harmonic potential of springs for cellular lattices and Hertz's contact potential of balls for granular lattices, respectively. The cubic symmetry of effective elasticity is demonstrated for the three types of cubic lattices. By taking the orientational average, isotropic elastic constants can be obtained for randomly oriented lattices. As the bond length changes with the prestress of the boundary layer and controls the thermoelastic behavior, a novel design method of lattice-based materials confined in a spherical shell is demonstrated to achieve zero thermal expansion and a positive temperature derivative of elasticity.
The lunar mare potassium (K)-, rare-earth elements (REEs)- and phosphorous (P)-rich (KREEP-rich) region is a unique late-stage product of magma crystallization, in which ilmenite and incompatible elements have high grades, thus forming a giant natural reservoir. The extraction and purification of the high-value metal resources in the KREEP-rich region not only meet the construction needs of the lunar base but also solve the problem of resource scarcity on Earth. In this study, photovoltaic elemental silicon (Si) was used as a collector to extract ilmenite resources, REEs, and nuclear energy elements from basalt in the lunar mare KREEP-rich region at 1873 K. Based on experimentation, the metals titanium (Ti) and iron (Fe) in the lunar mare ilmenite are found to be enriched and solidified in the form of Si-based alloys. The contents of valuable incompatible elements in the KREEP-rich area are also found to be enriched and contained in the incompatible trace elements (ITEs) phase of the alloy. Among them, REEs (e.g., cerium (Ce) and thulium (Tm)) and nuclear elements (e.g., thorium (Th) and uranium (U)) are found to account for 82.61 wt% of the ITEs phase. This process provides a simple and feasible scheme for the in-situ resource utilization (ISRU) of the lunar surface and is suitable for the extraction and enrichment of lunar metal resources.
Human habitats on the lunar surface have been planned and designed already since the beginning of the space age in the early 1960's, long before the successful Apollo missions, which for the first time brought humans to the Moon and safely back to Earth. While existing plans for manned lunar stations were postponed for a long time for various reasons, the interest in building permanent research stations on the surface of the Moon re-awoke in the late 1990s and early 2000s. Hereby, the focus turned more and more towards the lunar poles, where strong indications for the existence of water ice inside permanently dark craters were found. In this study we present a design for a lunar habitat, which makes maximal use of the natural resources available on the Moon, in particular in the vicinity of the poles, while at the same time the necessary material transfer from Earth to the lunar surface is minimized. We identify and study the sites around the lunar poles (both north and south pole) and present a design for a lunar habitat consisting of up to 16 greenhouses suitable for permanently housing and nourishing up to 32 humans. The greenhouses have a toroidal shape and are connected by tunnels. The horizontally incident sunlight is re-directed by a rotating mirror towards an artificial crater and from there through a transparent foil to the interior of the greenhouses. The main feature of our design is that the walls of the greenhouses as well as the attached rooms and tunnels are made of extremely light-weight materials, which are inflated to their final size simply by applying air pressure. Effective protection against harmful cosmic radiation is reached by covering greenhouses, living areas and connecting tunnels with a several metres thick layer of loose regolith. This cover ensures also a high level of thermal isolation, which helps to avoid too fast cooling of the interior during phases of total darkness. Finite element models of the thermodynamic behaviour of the suggested design confirm that life-friendly conditions can be created and kept over long time spans by using only the available solar illumination as power source and installing a state-of-art cooling system for the interior. In contrast to other concepts, the basic building blocks of this habitat design could be transported to the lunar surface by existing rocket systems offering a medium transport capacity, like Ariane 64, in combination with the planned European Large Logistics Lunar Lander Finally, various safety issues that might occur during setup and operation of such a lunar habitat, are discussed.
View Video Presentation: https://doi.org/10.2514/6.2022-4365.vid In the 2021 Fall term, the ASTE Studio focused creative efforts on how commercial human spaceflight in the United States could catalyze space activity around the globe and steer the future of human spaceflight. With an eye on NASA’s Gateway and Artemis projects, the CHASE project cast the net wide, to seek out synergies and collaborations sans policy limitations. By starting to explore the future of governmental and commercial activities in low Earth orbit, on the International Space Station, and evolving outward to encompass cislunar space and our Moon, the USC CHASE project imagined and created potential concepts that we feel are worthy of further investigation. Topics explored included commercially focused utilization of the International Space Station, Uses of a Human-tended Geostationary Space Station, Evolution and Uses of an Advanced Cislunar Communications Infrastructure, Importance of Establishing a sturdy Earth-Moon Logistics Channel to support 21st century cislunar traffic and a permanent human lunar surface presence. A scientific exploration mission for the Artemis lll crew to retrieve solar activity records to help build a much more complete solar behavior model over geologic time that can inform Climate Change on Earth and also explore the interior of a lunar lava tube, a concept for a Robot scout assistant rover for lunar surface crew in EVA, and Crew safety and rescue Infrastructure establishment before commencing Artemis missions that can also be used in case anomalies arise are proposed as well as the evolution of nuclear power systems for lunar applications. Several American space companies are sprouting that continue to broaden human spaceflight capability and expand CHASE allied engineering capacity needed to grow and mature this fully homegrown space industry ecology. Powered by the plummeting costs of components and methods like advanced additive manufacturing, a wide stable of launchers and private spacecraft are entering the space activity domain once considered the monopoly of governments. Commerce is the lifeblood of modern civilization. Healthy competition and agility, ingenuity and innovation are the drivers of economics and profit in this sector. We must continue to encourage real space commerce, especially human space activity, beyond the NASA vendor-buyer model. Fundamental economic sense drives all successful commerce. A sustainable business model requires a profit motive. [Profit = Revenue - Cost] is a fundamental formula for all sensible commerce. Monitoring and minimizing environmental impact is a prime concern in the fragile vacuum and weightlessness of Space. All these CHASE related activities, both domestic and around the globe bode well for the US to remain the beacon of the free world and at the forefront of space activity. Human space activity in particular, makes us the nexus for global cooperation and collaboration. That is a good sign for 21st century civilization, progressing step-by-step to build a peaceful, equitable and glorious future for humanity in space and on Earth. Synopses of visions created in the CHASE concept studio are presented. Recommendations are made for alternative architectures and mission profiles for both Gateway and Artemis programs. 2021 CHASE project slides may be accessed at : ASTE 527 Home (google.com)
In the 2021 Fall term, the ASTE Studio focused creative efforts on how commercial human spaceflight in the United States could catalyze space activity around the globe and steer the future of human spaceflight. With an eye on NASA's Gateway and Artemis projects, the CHASE project cast the net wide, to seek out synergies and collaborations sans policy limitations. By starting to explore the future of governmental and commercial activities in low Earth orbit, on the International Space Station, and evolving outward to encompass cislunar space and our Moon, the USC CHASE project imagined and created potential concepts that we feel are worthy of further investigation. Topics explored included Commercially focused Utilization of the International Space Station, Uses of a Human-tended Geostationary Space Station, Evolution and Uses of an Advanced Cislunar Communications Infrastructure, Importance of Establishing a sturdy Earth-Moon Logistics Channel to support 21 st century cislunar traffic and a permanent human lunar surface presence. A scientific exploration mission for the Artemis lll crew to retrieve solar activity records to help build a much more complete solar behavior model over geologic time that can inform Climate Change on Earth and also explore the interior of a lunar lava tube, a concept for a Robot scout assistant rover for lunar surface crew in EVA, and Crew safety and rescue Infrastructure establishment before commencing Artemis missions that can also be used in case anomalies arise are proposed as well as the evolution of nuclear power systems for lunar applications. Several American space companies are sprouting that continue to broaden human spaceflight capability and expand CHASE allied engineering capacity needed to grow and mature this fully homegrown space industry ecology. Powered by the plummeting costs of components and methods like advanced additive manufacturing, a wide stable of launchers and private spacecraft are entering the space activity domain once considered the monopoly of governments. Commerce is the lifeblood of modern civilization. Healthy competition and agility, ingenuity and innovation are the drivers of economics and profit in this sector. We must continue to encourage real space commerce, especially human space activity, beyond the NASA vendor-buyer model. Fundamental economic sense drives all successful commerce. A sustainable business model requires a profit motive. [Profit = Revenue-Cost] is a fundamental formula for all sensible commerce. Monitoring and minimizing environmental impact is a prime concern in the fragile vacuum and weightlessness of Space. All these CHASE related activities, both domestic and around the globe bode well for the US to remain the beacon of the free world and at the forefront of space activity. Human space activity in particular, makes us the nexus for global cooperation and collaboration. That is a good sign for 21st century civilization, progressing step-by-step to build a peaceful, equitable and glorious future for humanity in space and on Earth. Synopses of visions created in the CHASE concept studio are presented. Recommendations are made. Welcome to USC ASTE527 2021 CHASE Graduate Space Concept Synthesis Studio dear colleagues, where architectural and engineering minds work together to imagine the "what can be" of human spaceflight.
A tremendous effort has been expended to understand the lunar environment for scientific purposes as well as for the eventual drive to settle and create an extension of human civilization on the Moon and then Mars. We summarize these environmental challenges and identify two designs that are representative of current thinking for first- and second-generation lunar habitats. Interestingly, the basic habitat structural options have not fundamentally changed over the last half century, even though technical advances have occurred as has our understanding of the lunar environment. As such, the potential quality of the conceived habitats has improved without much change in their appearances. This paper is only meant to provide an overview of the subject and is not representative of the literature, which numbers in the tens of thousands of documents. The citations herein are a door to a subset of those vast references.
In-situ resource utilization on the Moon and/or Mars is a cutting-edge hotspot for exploring outer space. Lunar/Martian regolith is an in-situ natural resource for construction habitats and objects on the Lunar or Martian surface. Various manufacturing technologies have been designed for exploration of and settlement in space and other planets. This review provides a comprehensive overview of the most recent studies on several additive manufacturing (AM) technologies that can be applied to the Moon/Mars, including updated research on the environmental effects of the AM fabrication process such as temperature, gravity, and the vacuum atmosphere and the introduction of in-situ materials utilization focusing on characteristics, beneficiation, and treatment of Lunar/Martian soils. In addition, this study presents several possible designs and construction strategies of habitats under the extreme environment of Moon and Mars, including the arrangement strategies of multifunctional base clusters and the AM technologies of multi-layer defense bases. As a necessary unmanned construction process prior to human settlement on the Moon/Mars, AM technologies open up new opportunities for fabrication of intricate three-dimensional (3D) objects on Moon/Mars and are becoming a major driving force for utilizing in-situ resources in outer space.
In the Part 1 of two companion papers, a deployable composite cabin (DCC) for space habitats was introduced and its folding behaviour was comprehensively studied. This Part 2 paper is dedicated to present an analytical model for rapidly predicting the folding behaviour of the DCC. Based on the classical Euler-Bernoulli beam model, the geometric and physical equations describing the folding behaviour of the DCC were established in this paper. By combining Maclaurin series expansion, orthogonal Chebyshev polynomials, Galerkin method and Harmonic balance method, analytical models for predicting the load-displacement curve and shape function of the DCC were presented. The analytical solution of compressive strength was derived from the principle of minimum total complementary potential energy, classical laminate theory and Tsai-Hill failure criterion. In order to validate the analytical model proposed in this paper, the prediction results were compared with experimental results and numerical simulation results in the Part 1, and the three were in good agreement. Finally, the effect of geometric parameters (i.e. arc length, axial length and thickness of the thin plate) on the folding behaviour of the DCC was further analyzed by using the analytical model.
Considering the challenges of the huge temperature difference of lunar surface between day and night and the shortage of energy in Lunar Base at nighttime mode, this paper proposed a novel topology of self-driven thermal energy system (TES), combined with the power cycle and the ejector refrigeration cycle. The mathematical model of the TES is constructed to obtain the thermal performance under the design condition. Various characteristics of Te, Tre and Tc are studied due to the diversity and fluctuation of exhausted heat grade from equipment in the lunar base. Four typical conditions considering the requirements of heat dissipation and cooling capacity are analyzed when astronauts' schedule and external solar radiation intensity are changed. Results show that the TES realizes self-driven operation without extra power under the design condition and provide 10.26 kW cooling capacity for manned module. Under off-design conditions, evaporation temperature has a significant impact on the refrigeration performance of the TES. When evaporation temperature rises from 312.15K to 318.15K, cooling capacity increases from 2.99 kW to 16.02 kW and COP increases from 0.10 to 0.53. When astronauts’ schedule changes from sleeping to working at nighttime mode, cooling capacity rises from 3.78 kW to 11.53 kW, meeting the demand for refrigeration. Moreover, the TES has better heat dissipation performance when it is installed in the area above 35 °N. This system with obvious self-driven characteristic will provide huge potential capacity on energy saving and weight reducing, which supplies novel insights on the technical operation of Lunar Base in the future.
Understanding the effect of radiation on materials is fundamental for space exploration. Energetic charged particles impacting materials create electronic excitations, atomic displacements, and nuclear fragmentation. Monte Carlo particle transport simulations are the most common approach for modeling radiation damage in materials. However, radiation damage is a multiscale problem, both in time and in length, an aspect treated by the Monte Carlo simulations only to a limited extent. In this chapter, after introducing the Monte Carlo particle transport method, we present a multiscale approach to study different stages of radiation damage which allows for the synergy between the electronic and nuclear effects induced in materials. We focus on cumulative displacement effects induced by radiation below the regime of hadronic interactions. We then discuss selected studies of radiation damage in materials of importance and potential use for the exploration and settlement on the Moon, ranging from semiconductors to alloys and from polymers to the natural regolith. Additionally, we overview some of the novel materials with outstanding properties, such as low weight, increased radiation resistance, and self-healing capabilities with a potential to reduce mission costs and improve prospects for extended human exploration of extraterrestrial bodies.
Soil analysis is a significant part of space exploration. Nowadays, great attention is given to soil investigation on the Moon, and special missions are being planned to carry out analyses of lunar soil in situ (Valero et al., 2007). Mass spectrometry is a proven method that is commonly used for identifying the chemical composition of the soil. One of the best candidates for a mass spectrometer for this purpose is a mass spectrometer based on an ion trap, which has high mass resolution, a low weight, a compact size, and low power consumption. Among the existing ion traps (Kingdon traps, Penning traps, Radiofrequency Paul traps, and Radiofrequency linear traps), a Kingdon trap of unique design would be a viable option for many applications.
However, disturbances in the space environment negatively affect the use of an ion trap. One of these harmful effects in the lunar environment is the wide range of temperatures. Heating or cooling causes deformation of the geometry of the ion trap electrodes, reducing the accuracy of the measurements.
The current research aims to compare metal and ceramic ion traps and to investigate how the material used in manufacturing affects the performance of the mass spectrometer. Analysis of thermally-induced deformations was used as the primary method of the research. We manufactured models of metal and ceramic ion traps, analyzed the effects of electrode deformation on the analytical characteristics of the mass spectrometer, conducted thermal deformation analysis, and validated our results.
The ceramic ion trap (56.3µm) shows less thermal deformation in comparison with the metal one (105.5µm). The thermal expansion that is higher than 50 micrometers significantly affects the performance of the instrument. The loss time of the signal decreased twice reduces the resolution of the ion trap also by a factor of two. We propose introducing corrections to the shape of the surface that electrodes have at room temperature so that after thermal compression at 97K (average temperature of the Moon Polar regions), the surface has a shape corresponding to the ideal performances of the instrument.
The next step for the exploration of space seems to require the human participation by means of a long-lasting lunar outpost. Therefore, this paper attempts to review the up-to-date knowledge regarding prominent issues surrounding the construction stage of a permanent base on the Moon in the light of the 3D printing process. In this context, a number of significant and specific issues are presented and discussed in a detailed manner to determine both the state-of-the-art position of the related literature and the relevant fields for improvement and implications. As a result, the use of heterogeneous and collective swarms of ground robots through a decentralized approach seems reasonable for the 3D printing tasks. However, as it is an emerging technology, it has to be improved further and tested in a terrestrial context as well as on the Moon. In this regard, it is a must to investigate precisely if the solar energy will be adequate for the operation of robots during preparation, transportation, and printing processes of local and Earth-based construction materials. In terms of structural needs, a composite shelter, including (i) an inner inflatable shell with a three-layer membrane, (ii) an outer concrete layer with regolith, polymer, and reinforcing fibers, and (iii) an outermost shield with raw regolith, will likely be viable. However, sieving and binding issues during the preparation phase of concrete under vacuum and microgravity conditions must be solved efficiently.
Space exploration is gaining new momentum. A near-term goal set by NASA is to return humans to the Moon and establish a sustainable presence on the lunar surface to enable more repeatable and affordable deeper space expeditions. Lunar dust is one of the dangerous environmental hazards causing serious problems for exploration activities. In this paper, a dynamic model is developed and used to study the impact of lunar dust on the performance of a thermal management system for a lunar habitat that is comprised of a vapor-compression cycle heat pump and a radiator loop. A heat pump to lift the heat rejection temperature is required due to high lunar daytime surface temperatures. Parametric studies on radiator size, percentage of dust coverage on the radiator, and lunar habitat location are carried out. The results show that lunar deposits can significantly increase the power consumption of the thermal management system. The lunar dust contamination problem raises the requirement for redundant design of the radiator loop for fault tolerance. A synergetic design of a thermal management system, a power generation system and robotic maintenance system is proposed to achieve maximal mass reduction for a whole lunar habitat system.
Deployable lunar structures have been and are being developed as an appropriate solution to the volumetric limitations of cargo mission flights. A deployable lunar habitat consisting of linear and planar elements connected through simple movable joints is introduced. This new structure is made of some linear units consisting of two types of scissor-like elements (SLE): 1) a modified polar scissor-like element and 2) a closed-loop of angulated scissor-like elements. After conducting theoretical research on lunar habitats, the evaluation criteria of transformable lunar structures are derived and then many new concepts are evaluated. The design considerations of such structures are discussed, and a proper form for these habitat types is selected. An experimental study is run to assess the best deployment strategy for the whole structure. By introducing the dimensional properties of the lunar habitats through physical and digital modeling process per crewmember, the derived alternatives from the previous stage are analyzed and the best transformation strategy that meets the aforementioned considerations is developed. Providing relatively high degrees of protection against environmental hazards through the combination of rigid plates with membrane, this proposed structure reduces the required extravehicular activity (EVA) time for assembly because of its quick and simple deployment mechanism. The folded state of the structure provides a low volume for the integration of subsystems.
This 2020 USC TWINS project, following the 2018 ADAM Project and the 2019 MAXIM, continues to weave a narrative that wishes humanity to return to the Moon at the earliest, to retire the known risks, gain the vital experience needed to push on to Mars and settle other worlds. Hard data is what good engineers depend on to build and evolve reliable systems. Narrative, the art of storytelling, is at least as important to the global public, as it to the exploration community. In the 2019 MAXIM Project we pushed the human emotion button for creating a wholesome narrative of preserving the heritage of Apollo for posterity, while reminding the world what our nation accomplished on an extra-terrestrial surface five decades ago, and also chose to pay homage and evoke nostalgia among the heroes of the Apollo program. Leveraging what has been accomplished to date, the 2020 USC ARTEMIS:TWINS project offers concepts for both the Commercial Lunar Payload Service(CLPS) precursory missions for ARTEMIS and some alternative options for the early missions of the lunar GATEWAY project to bring back hard data that is vital for evolving safe and reliable systems for interplanetary transit crew and vehicles. In this 2020 CLPS+GEMINI TWINS project we depict both some precursory and early human spaceflight missions that could enrich and breathe dynamism and excitement into the narrative of both the NASA CLPS effort and the GATEWAY architecture. It seems possible to meet both the national and the international objectives with ARTEMIS and GATEWAY.
Lava tubes are buried channels that transport thermally insulated lava. Nowadays, lava tubes on the Moon are believed to be empty and thus indicated as potential habitats for humankind. In recent years, several studies investigated possible lava tube locations, considering the gravity anomaly distribution and surficial volcanic features. This article proposes a novel and unsupervised method to map candidate buried empty lava tubes in radar sounder data (radargrams) and extract their physical properties. The approach relies on a model that describes the geometrical and electromagnetic (EM) properties of lava tubes in radargrams. According to this model, reflections in radargrams are automatically detected and analyzed with a fuzzy system to identify those associated with lava tube boundaries and reject the others. The fuzzy rules consider the EM and geometrical properties of lava tubes, and thus, their appearance in radargrams. The proposed method can address the complex task of identifying candidate lava tubes on a large number of radargrams in an automatic, fast, and objective way. The final decision on candidate lava tubes should be taken in postprocessing by expert planetologists. The proposed method is tested on both a real and a simulated data set of radargrams acquired on the Moon by the Lunar Radar Sounder (LRS). Identified candidate lava tubes are processed to extract geometrical parameters, such as the depth and the thickness of the crust (roof).
Before humans had even stepped foot on the lunar surface, the idea of establishing a base was discussed extensively, with design possibilities and environmental studies. The lunar environment presents numerous challenges to surface structural designs as well as human survival. This paper reviews concepts and challenges and proposes a new design concept based on a hybrid-inflatable framework.
Introduction: In 2009, three huge pits were discovered on the Moon in image data acquired by the SELENE Terrain Camera. Their diameters and depths are several tens of meters or more.[1-3] They are possible skylight holes opening on large subsurface caverns such as lava tubes, [1] by analogy with similar pits found on Mars.[4] This possibility was enhanced significantly by LRO oblique observations; large openings were observed horizontally at the floors of the pits.[5] Robinson et al. (2012)[5] claim at least two possibilities for the large caverns associated with the skylight holes: a lava tube or a magma chamber. Lava tubes are normally elongated in the horizontal direction. In contrast, magma chambers may not have large horizontal extensions but instead may have drops like a sink around their inner walls as illustrated by Robinson et al. (2012).[5] Lunar caverns are protected from radiation, micrometeorites, and extreme temperatures, and thus are expected to be shelters in which humans will construct lunar bases. Lava tubes are likely more appropriate for lunar base construction than magma chambers. It is thus significant to investigate whether a lunar subsurface cavern is a lava tube or a magma chamber. We analyze radar echo data acquired by the Lunar Radar Sounder (LRS) onboard SELENE (Kaguya) to determine whether there is any suggestion of the existence of elongated lava tubes along rille-A named by Greeley (1971).[6] The Marius Hills skylight Hole (MHH) is on the rille.
This special issue on in situ resource utilization (ISRU) was borne from the reality that in order for humanity to evolve into a spacefar-ing civilization, it will need to be able to gather, process, and use materials at the site where explorations are made and settlements are planted. This ability to wean ourselves from Earth is critical, and it will be coupled to automated devices and robots. Astronauts are now our construction workers in space and will likely be so when we return to the Moon and go to Mars, but the severe environments make reliance on humans for building our space civilization not feasible. The guest editors would like to express their gratitude to all the authors for their contributions and for graciously proceeding through the review process. The reviewers are likewise appreciated for the time-consuming effort of studying the submitted manuscripts and then providing very useful feedback to the authors who can improve their manuscripts.
There is growing interest in the possibility that the resource base of the
Solar System might in future be used to supplement the economic resources of
our own planet. As the Earth's closest celestial neighbour, the Moon is sure to
feature prominently in these developments. In this paper I review what is
currently known about economically exploitable resources on the Moon, while
also stressing the need for continued lunar exploration. I find that, although
it is difficult to identify any single lunar resource that will be sufficiently
valuable to drive a lunar resource extraction industry on its own
(notwithstanding claims sometimes made for the 3He isotope, which I find to be
exaggerated), the Moon nevertheless does possess abundant raw materials that
are of potential economic interest. These are relevant to a hierarchy of future
applications, beginning with the use of lunar materials to facilitate human
activities on the Moon itself, and progressing to the use of lunar resources to
underpin a future industrial capability within the Earth-Moon system. In this
way, gradually increasing access to lunar resources may help 'bootstrap' a
space-based economy from which the world economy, and possibly also the world's
environment, will ultimately benefit.
3D-printing technologies are receiving an always increasing attention in
architecture, due to their potential use for direct construction of
buildings and other complex structures, also of considerable dimensions,
with virtually any shape. Some of these technologies rely on an
agglomeration process of inert materials, e.g. sand, through a special
binding liquid and this capability is of interest for the space
community for its potential application to space exploration. In fact,
it opens the possibility for exploiting in-situ resources for the
construction of buildings in harsh spatial environments. The paper
presents the results of a study aimed at assessing the concept of 3D
printing technology for building habitats on the Moon using lunar soil,
also called regolith. A particular patented 3D-printing technology -
D-shape - has been applied, which is, among the existing rapid
prototyping systems, the closest to achieving full scale construction of
buildings and the physical and chemical characteristics of lunar
regolith and terrestrial regolith simulants have been assessed with
respect to the working principles of such technology. A novel lunar
regolith simulant has also been developed, which almost exactly
reproduces the characteristics of the JSC-1A simulant produced in the
US. Moreover, tests in air and in vacuum have been performed to
demonstrate the occurrence of the reticulation reaction with the
regolith simulant. The vacuum tests also showed that evaporation or
freezing of the binding liquid can be prevented through a proper
injection method. The general requirements of a Moon outpost have been
specified, and a preliminary design of the habitat has been developed.
Based on such design, a section of the outpost wall has been selected
and manufactured at full scale using the D-shape printer and regolith
simulant. Test pieces have also been manufactured and their mechanical
properties have been assessed.
The moon has recently regained the interest of many of the world's space agencies. Lunar missions are the first steps in expanding manned and unmanned exploration inside our solar system. The moon represents various options; it can be used as a laboratory in low gravity, it is the closest and most accessible planetary object from the Earth, and it possesses many resources that humans could potentially exploit. This paper has two objectives: to review the current status of the knowledge of lunar environmental requirements for future lunar structures, and to attempt to classify different future lunar structures based on the current knowledge of the subject. The paper divides lunar development into three phases. The first phase is building shelters for equipment only; in the second phase, small temporary habitats will be built, and finally in the third phase, habitable lunar bases will be built with observatories, laboratories, or production plants. Initially, the main aspects of the lunar environment that will cause concerns will be lunar dust and meteoroids, and later will include effects due to the vacuum environment, lunar gravity, radiation, a rapid change of temperature, and the length of the lunar day. This paper presents a classification of technical requirements based on the current knowledge of these factors, and their importance in each of the phases of construction. It gives recommendations for future research in relation to the development of conceptual plans for lunar structures, and for the evolution of a lunar construction code to direct these structural designs. Some examples are presented along with the current status of the bibliography of the subject.
The realization of the renewed exploration of the moon presents many technical challenges; among them is the survival of lunar-surface assets during periods of darkness when the lunar environment is very cold. Thermal wadis are engineered sources of stored solar energy using modified lunar regolith as a thermal storage mass that can supply energy to protect lightweight robotic rovers or other assets during the lunar night. This paper describes an analysis of the performance of thermal wadis based on the known solar illumination of the moon and estimates of producible thermal properties of modified lunar regolith. Analysis has been performed for the lunar equatorial region and for a potential outpost location near the lunar south pole. The calculations indicate that thermal wadis can provide the desired thermal energy and temperature control for the survival of rovers or other equipment during periods of darkness.
While popular science writers typically describe the benefits to be derived from their favorite very large space development project in detail, their treatment of the crucial initial capitalization of such projects is typically sparse or implausible. Capitalization is a crucial problem for these projects because the total capital investment required is very large and the investment takes a very long time before producing economic returns. "Chunky" investments are unattractive to most private investors and lenders. Very large space development projects are best understood as massive public works projects which are necessary to open frontiers. Despite the libertarian sentiments in much of the popular science writing on very large space development projects, government would likely have to play a large role in capitalizing such projects. Space development enthusiasts typically explain the significance of their favorite very large space projects−whether constructing orbital colonies or cities beneath the surface of the Moon, terraforming Mars or Venus, or launching interstellar spacecraft−in terms of their promise to produce vast new wealth, open frontiers to serve as social "safety valves" for the ambitious or the dissenting, generate the novel problems that drive dramatic advances in science and engineering, provide new sources of natural resources, and permit population dispersal to assure the long term survival of our species. Without question, these are all laudable reasons for the adventure of space and any very large space project would probably meet several of these objectives. However, if the economic and social promise of these projects is so extraordinary, and if the social losses which result from failing to undertake them are so large, why haven't humans embarked on them? Why aren't we even close to beginning one of these great enterprises? Given the assertion made by many space development enthusiasts that the basic technology needed for their favorite projects already exists or can be developed from the available science, asking these questions is entirely fair. The answers must be found in political economy, some rudimentary understanding of which will be necessary before realistic planning for any very large space project can begin.
1] We discovered a vertical hole on the Moon, which is a possible lava tube skylight, using data from SELENE's two high-resolution cameras: the Terrain Camera and the Multi-band Imager. The hole is nearly circular, 65 m in diameter, and located in a sinuous rille at the Marius Hills region, a volcanic province on the lunar nearside. We observed the hole at various solar illumination conditions and estimated its depth to be 80 to 88 m. The depth/diameter ratio is much larger than for typical impact craters. There are neither conspicuous deposits indicating volcanic eruptions from the hole, nor are there pit craters adjacent to the hole that could be related to an underlying fault or dike. The area around the hole is covered by a thin (20 to 25 m) lava sheet, which may help protect the lava tube from collapse due to meteorite bombardment. Citation: Haruyama, J., et al. (2009), Possible lunar lava tube skylight observed by SELENE cameras, Geophys. Res. Lett., 36, L21206, doi:10.1029/2009GL040635.
A lunar base is an essential part of all the new space exploration programs because the Moon is the most logical first destination in space. Its hazardous environment will pose challenges for all engineering disciplines involved. A structural engineer's approach is outlined in this paper, discussing possible materials and structural concepts for second-generation construction on the Moon. Several different concepts are evaluated and the most reasonable is chosen for a detailed design. During the design process, different solutions—for example, for the connections—were found. Although lunar construction is difficult, the proposed design offers a relatively simple structural frame for erection. A habitat on the Moon can be built with a reasonable factor of safety and existing technology. Even so, we recognize the very significant difficulties that await our return to the Moon.
The particle size distribution PSD of lunar dust, the 20 m portion of the regolith, was determined as an initial step in the study of the possible toxicological effects it may have on the human respiratory and pulmonary systems. Utilizing scanning electron microscopy, PSDs were determined for Apollo 11 10084 and 17 70051 dust samples, as well as lunar dust simulant JSC-1Avf. The novel methodology employed is described in detail. All measured PSDs feature a log-normal distribution having a single mode in a range 100– 300 nm for lunar dust samples, but the lunar simulant has a mode at 600 nm.
The Langley high energy nucleon transport computer code BRYNTRN is used to predict time-integrated radiation dose levels at the lunar surface due to high proton flux from solar flares. The study addresses the shielding requirements for candidate lunar habitat configurations necessary to protect crew members from these large and unpredictable radiation fluxes. Three solar proton events have been analyzed, and variations in radiation intensity in a shield medium due to the various primary particle energy distributions are predicted. Radiation dose predictions are made for various slab thicknesses of a lunar soil model. Results are also presented in the form of dose patterns within specific habitat configurations shielded with lunar material.
The economic benefits of NASA programs are discussed. Emphasis is given to an analysis of indirect economic benefits which estimates the effect of NASA programs on employment, personal income, corporate sales and profits, and government tax revenues in the U.S. and in each state. Data are presented that show that NASA programs have widely varying multipliers by industry and that illustrate the distribution of jobs by industry as well as the distribution of sales.
This book carries out approximate estimates of the costs of implementing ISRU on the Moon and Mars. It is found that no ISRU process on the Moon has much merit. ISRU on Mars can save a great deal of mass, but there is a significant cost in prospecting for resources and validating ISRU concepts. Mars ISRU might have merit, but not enough data are available to be certain. In addition, this book provides a detailed review of various ISRU technologies. This includes three approaches for Mars ISRU based on processing only the atmosphere: solid oxide electrolysis, reverse water gas shift reaction (RWGS), and absorbing water vapor directly from the atmosphere. It is not clear that any of these technologies are viable although the RWGS seems to have the best chance. An approach for combining hydrogen with the atmospheric resource is chemically very viable, but hydrogen is needed on Mars. This can be approached by bringing hydrogen from Earth or obtaining water from near-surface water deposits in the soil. Bringing hydrogen from Earth is problematic, so mining the regolith to obtain water seems to be the only way to go. This will require a sizable campaign to locate and validate useable water resources. Technologies for lunar ISRU are also reviewed, even though none of them provide significant benefits to near-term lunar missions. These include oxygen from lunar regolith, solar wind volatiles from regolith, and extraction of polar ice from permanently shaded craters.
The goal of this paper is to provide an overview of ideas and proposals for space stations and space colonies since the last hundred years, starting with the Russian space pioneer Tsiolkovsky and focusing on some recent projects of the author. A permanent lunar base will be the first step, but Moon and Mars have much less gravity than Earth. For this reason engineers and architects were searching for space habitat design using artificial gravity. Rotating space stations -modular, toroidal, spherical and cylindrical- may provide a comfortable environment for astronauts and space settlers of the future. Within the so called “habitable zone” between Earth and Mars natural sunlight can be used for the illumination of space stations and space colonies. In the long run asteroids and the Moon will be mined and may provide the building material for large self-sustaining space colonies. Water can be taken from icy Near Earth Asteroids. We discuss methods of meteorite and radiation shielding as well as thermal protection. Hollow asteroids can be used as a natural shelter for space stations after the end of the mining process.
Technology transfer has been a cornerstone of the justification for public expenditure of space technology development programs since at least the creation of NASA out of its predecessor agencies. Research into its mechanisms has, however, been largely qualitative and focused on actively managed, one-way transfer of technology from agencies to industry. In this paper we consider the effects of a wider range of mechanisms by which space agencies affect the technical knowledgebase, and examine the Contingent Effectiveness Model as a useful framework for formalizing comparative analysis of transfers.
The most widely available lunar resources are the local regolith and power from sunlight. In-situ vitrification technology and techniques exist to construct paving, equipment foundations and radiation proof shelters. New methods are proposed for making dust free chambers strong enough to support atmospheric pressure. These methods require minimal excavation and should enable remote operation from Earth. The equipment could provide feedstock for a cast basalt industry for structural elements and fittings. By-products would be volatiles and iron. Consumables and high tech equipment only would need to be imported from Earth. Power required is half that for cement production.
The idea of melting in-situ lunar regolith to create underground vitrified structures has been developed previously [1]. Using this technique, the possibility of establishing long term bases/settlements on the Moon, Mars, Mercury or any other rocky body is discussed. There are two basic obstacles to such settlements: gravity and radiation, and solutions to both problems are offered utilizing subsurface structures fabricated using vitrification techniques. Such structures could house large settlements of humans in comfort and safety in conditions similar to those envisioned with space based habitats. These settlements would have access to all the material and energy resources available to the planet or moon on which they are constructed. Such settlements offer protection to their inhabitants from radiation events or asteroid strikes that could destroy an Earth-based civilization.
Introduction: The thermal energy balance of any space mission element, whether it is a spacecraft, a permanent and crewed lunar base, or a space suit, is derived as a function of heat released by personnel and/or components installed within the outer shell and heat received from the surrounding environment. © 2012 Springer-Verlag Berlin Heidelberg. All rights are reserved.
Introduction: The Moon is the nearest celestial body to the Earth. As such, it has long been investigated to understand its formation and evolution, as a paradigm for better understanding the terrestrial planets, as well as all airless bodies in our solar system (e.g., Vesta, Phobos). The Moon's proximity to the Earth--more than one hundred times closer than any planet -- makes it a convenient target for exploration by spacecraft. Since the dawn of the space age in the previous century, we have explored the Moon with several spacecraft and even succeeded in sending astronauts there. One of the lessons of those explorations that hinders any future lunar expeditions is the severe conditions on the lunar surface. The lack of an atmosphere (10-12 torr) means that cosmic/galactic/solar rays, as well as the many micrometeorites directly striking the surface; in addition, surface temperatures vary widely, over a day-night range of more than 300 K. © 2012 Springer-Verlag Berlin Heidelberg. All rights are reserved.
The solar radiation absorbed in massive building components is stored and later emitted as long-wave thermal radiation into the interior space. Heat storage capacity is directly related to the mass of the building envelope surrounding this space and particularly that of high-mass, homogeneous earthen or cementitious material. A thermal storage cycle is created by the time-lag effect if sufficient mass is available. A similar strategy applied to the lunar and/or Martian regolith would provide a surface structure with micrometeorite and radiation protection, thermal insulation, and natural supplemental heat energy that would significantly reduce the energy requirements met by mechanical equipment. HEAT2 is an energy simulation program that solves heat transfer problems using the partial differential heat conduction equation in two dimensions with the method of explicit finite differences. HEAT2 simulation data suggests that, although thermal mass is most suitable for climates where desired indoor temperatures fall within a large daily external temperature gradient, the heat storage cycle is least effective at the annual extremes occurring in midwinter and in midsummer. A more moderate climate will allow the heat storage cycle to modulate between positive and negative heat flows which are then shifted to align with peak load conditions, reducing energy demand. Also, diurnal and seasonal temperature gradients can initiate a sequence of phase transitions in the soil's moisture content affecting the overall conductivity. This study will present a more accurate explanation of the heat transfer processes occurring in soils of varying compositions when thermal properties are altered by transient climatic conditions.
An igloo-shaped magnesium structure, supported on a sintered regolith, covered by sandbags of regolith shielding, and made using rapid manufacturing technologies is proposed as a potential design of a lunar structure. Also, a thermal analysis is carried out to study the effect of the regolith shielding as well as the sensitivity of such designs to measurement uncertainties of regolith and sintered thermal properties. It is shown that 3-m-thick regolith shielding can insulate the structure regardless of its location on the Moon.
Many space-related impact studies have been carried out in the past, but there is no conclusive, comprehensive evaluation of the economic and social effects of public investments in space. Such evaluations are not easy to perform, for several reasons: the space sector is not a recognised category in official statistics; social benefits, which are likely to be very important, are hard to assess; and impacts from R&D are complex and occur in the long term. However, important steps can be made towards better evaluation of impacts. The full set of impacts of space investments may be simultaneously evaluated from both a ‘bottom-up’ and a ‘top-down’ perspective. In the bottom-up perspective, each effect is measured separately, while the top-down perspective provides a framework for integrating the effects. Although both perspectives have their own advantages and drawbacks, combining them yields both detailed and integrated results. Our discussion of the bottom up approach starts by identifying an extensive list of impacts. Next, data availability issues and methodological improvements are identified, leading to recommendations on programmes to collect data and perform case studies. Finally, suggestions are made for presenting impacts in the form of a scoreboard. The core of the top-down evaluation methodology proposed is social cost benefit analysis. Effects are weighted, where possible, on the basis of observed market prices or other estimations of monetary values. For effects that are hard to measure or monetize, multi-criteria analysis can be applied using surveys and expert opinion. Our core recommendations are to clearly define the space sector, to collect additional data, and to use improved methodologies. Social, strategic and environmental impacts deserve special attention, aiming at a more comprehensive coverage of impacts. Comprehensive evaluations can contribute to more upport for space expenditures.
One of the biggest challenges of the exploration of the Moon is the
survival of the crew and the lunar assets during the lunar night. The
environmental conditions on the lunar surface and its cycle, with long
periods of darkness, make any long mission in need of specific amounts
of heat and electricity to be successful. We have analyzed two different
systems to produce heat and electricity on the Moon's surface. The first
system consists of Thermal Wadis, sources of thermal power that can be
used to supply heat to protect the exploration systems from the extreme
cold during periods of darkness. Previous results showed that Wadis can
supply enough heat to keep lunar devices such as rovers above their
minimum operating temperature (approximately 243 K). The second system
studied here is the Thermal Energy Storage (TES), which is able to run a
heat engine during the lunar night to produce electricity. When the Sun
is shining on the Moon's surface, the system can run the engine directly
using the solar power and simultaneously heat a thermal mass. This
thermal mass is used as a high temperature source to run the heat engine
during the night. We present analytical and numerical calculations for
the determination of an appropriate thermal mass for the TES system.
The lunar surface is characterized by a collisionally evolved regolith resulting from meteoroid bombardment. This lunar soil consists of highly angular particles in a broad, approximately power law size distribution, with impact-generated glasses. The regolith becomes densified and difficult to excavate when subjected to lunar quakes or, eventually, manned and unmanned activity on the surface. Solar radiation and the solar wind produce a plasma sheath near the lunar surface. Lunar grains acquire charge in this environment and can exhibit unusual behavior, including levitation and transport across the surface because of electric fields in the plasma sheath. The fine component of the lunar regolith contributes to the operational and health hazards posed to planned lunar expeditions. In this paper we discuss the mechanical response of the regolith to anticipated exploration activities and review the plasma environment near the lunar surface and the observations, models, and dynamics of charged lunar dust.
A process is well underway in which the scientific, technical and cultural information vital to our society is stored in digital form within a limited number of computer facilities. This practice is vulnerable to a variety of catastrophes which would destroy our knowledge base in addition to the losses they caused to population and structures. The Alliance to Rescue Civilization (ARC) proposes that a staffed data backup facility be constructed in a secure location, with the Moon as the site of choice. If Earth's population were destroyed entirely, the lunar sanctuary could serve to repopulate the planet.
A steady-state model for first-order magnitude estimates of lunar base masses is presented. The main focus of the model is the derivation of initial and annual resupply mass estimates for a lunar base at certain development stages. These estimates are not only a function of several thousand input parameters and boundary conditions such as crew size; lunar base location; and environmental conditions, but also specific system masses; specific power requirements; and specific thermal loads. This integrated lunar base model indicates which systems and subsystems have the greatest mass impact on the overall base. Also, brief overviews of possible activities at a lunar base and of lunar development strategies are given.
The establishment of a permanent human presence on other planets will require establishing permanent infrastructure in new environments. Civil engineers select, define, and implement solutions to infrastructure design problems in unique environmental contexts. Wind and seismic loading are two examples of constraints long familiar to terrestrial civil engineering. Designing structrues for lunar exploration, development and eventual settlement will make use of the same design processes already practiced by the civil engineering profession. However, the extensive experience base resulting from centuries of terrestrial work does not adequately prepare civil engineers for the unprecedented constraints and environmental conditions that are encountered in space. The limited knowledge we already have about the Moon (mostly from the Apollo program) is a place to start. By assimilating and working with this knowledge, those pursuing the design of lunar base structures can begin to produce realistic and valid design solutions. The paper presents technical, operations, and programmatic issues that the writers consider fundamental to understanding the facts of life in this promising new design arena.
This paper is a design study for a modular Lunar Base built of at least six cylindrical modules. For launching an ARIANE-Rocket with a payload of 12ton can be used.To land the modules on the moon the author has designed a Teleoperated Rocket Crane, which is assembled in the Lunar Orbit. The modules are made of aluminium sheets, using a double-shell structure to protect a crew of eight astronauts from radiation, micrometeorites, heat and low temperatures during the lunar night.Lunar material (regolith) is used for shielding.
The morphology shape and texture of dust fractions of five Apollo lunar soils and a lunar dust simulant, JSC-1Avf, was studied using scanning electron microscopy. Shape aspect ratio and complexity of particles was described based on the two-dimensional projection images. The distributions of aspect ratio and complexity of particles are reported. It was determined that the Apollo lunar dust particles consist mainly of impact-produced glass, with complicated morphologies, extensive surface areas per grain, and sharp, jagged edges. Importantly, many grains contain elaborate vesicular textures, representing minute agglutinates. Dust simulant JSC-1Avf also has similar shapes as lunar dust, but differs in surface texture and area smooth and nonvesicular. These data provide information for toxicity studies of lunar dust and for selecting a suitable lunar dust simulant.
Recent advances in materials technology have improved the performance capabilities of inflatable, flexible composite structures, which have increased their potential for use in numerous space applications. Space suits, which are comprised of flexible composite components, are a good example of the successful use of inflatable composite structures in space. Space suits employ inflatables technology to provide a stand alone spacecraft for astronauts during extra-vehicular activity. A natural extension of this application of inflatables technology is in orbital or planetary habitat structures. NASA Johnson Space Center (JSC) is currently investigating flexible composite structures deployed via inflation for use as habitats, transfer vehicles and depots for continued exploration of the Moon and Mars.
Inflatable/deployable structures are under consideration as habitats for future Lunar surface science operations. The use of non-traditional structural materials combined with the need to maintain a safe working environment for extended periods in a harsh environment has led to the consideration of an integrated structural health management system for future habitats, to ensure their integrity. This article describes recent efforts to develop prototype sensing technologies and new self-healing materials that address the unique requirements of habitats comprised mainly of soft goods. A new approach to detecting impact damage is discussed, using addressable flexible capacitive sensing elements and thin film electronics in a matrixed array. Also, the use of passive wireless sensor tags for distributed sensing is discussed, wherein the need for on-board power through batteries or hardwired interconnects is eliminated. Finally, the development of a novel, microencapuslated self-healing elastomer with applications for inflatable/deployable habitats is reviewed.
Visions about the establishment of a lunar base and development of the Moon for scientific, technical and commercial ends have been on the political agenda since the beginning of the Space Age. In the past few years a number of spacefaring nations, including the USA, European states through ESA, Japan, India, China and Russia have proposed missions directed at the robotic and human exploration and development of the Moon. This paper argues that an important factor in advancing these missions lies in a partnership between the pubic, governmental sector and the private sector. The paper analyzes the dynamics of this partnership as applied to the case of the US Vision for Space Exploration. The results of the analysis suggest that public–private partnerships directed at lunar development and commerce depend on how government reduces risks for the private sector. The risks identified and discussed herein include political and legal risks, technological risks, and financial and market risks.
There is considerable interest at the present time to design a thermal control system (TCS) for a lunar base. Conventional techniques cannot be used for the purpose due to the lack of a readily available temperature sink during most of the lunar day. The lunar surface near the equatorial regions reaches a maximum of about 390 K during the 336-h lunar day. The projected range of temperatures for operation of sensors and conditioned habitat spaces is 270–293 K. A heat pump augmented TCS can be used to increase the operating temperature of the radiator, thereby enabling heat rejection. Rankine, absorption, and reverse Brayton cycle heat pumps with various working fluids are examined to identify the optimal cycle and working fluid combination. A base-line cooling load of 100 kW to be rejected at 270 K is used in the analysis. A Rankine cycle heat pump operating with R11 as the working fluid and R717 as a rejection loop coolant provides an optimal total TCS mass of 5940 kg at a radiator temperature of 362 K.
Thesis--University of Illinois. Vita. Includes bibliographical references (leaves 144-150). Microfilm. s
Radiation protection assessments are performed for advanced Lunar and Mars manned missions. The Langley cosmic ray transport code and the nucleon transport code are used to quantify the transport and attenuation of galactic cosmic rays and solar proton flares through various shielding media. Galactic cosmic radiation at solar maximum and minimum, as well as various flare scenarios are considered. Propagation data for water, aluminum, liquid hydrogen, lithium hydride, lead, and lunar and Martian regolith (soil) are included. Shield thickness and shield mass estimates required to maintain incurred doses below 30 day and annual limits (as set for Space Station Freedom and used as a guide for space exploration) are determined for simple geometry transfer vehicles. On the surface of Mars, dose estimates are presented for crews with their only protection being the carbon dioxide atmosphere and for crews protected by shielding provided by Martian regolith for a candidate habitat.
The present status of lunar knowledge based on U.S. and USSR lunar missions and the continuing analysis of lunar samples and data is reviewed. Particular attention given to exploration, samples, and recent concepts of the moon; the lunar environment; lunar surface processes; the lunar minerals, rocks, and regolith; chemical elements in the moon; physical properties of the lunar surface; and global and regional data about the moon.
An increasing number of lunar base construction programs are in the process of developing lunar resources such as helium 3. The objective of the present work is to evaluate the temperature and humidity control system, which will allow man to live and work on the moon while developing lunar resources. The results of thermal load calculation show that the load of electric lighting is a 80 to 90% of the cooling load in the habitat module and that only the cooling function is required for temperature control. Due to this, a fluorocarbon refrigerant heat pump system was selected to satisfy reliability, energy consumption, size and weight requirements for the lunar base equipment. According to the load calculation, occupants will feel discomfort due to radiant heat from lighting fixtures. To resolve this problem, an air conditioning system, used in combination with forced convective cooling and panel cooling on the ceiling, was adopted in the living space. Moreover, the experiment on the ground was carried out to evaluate the effects of panel cooling.
For many years it has been suggested that lava tubes on the Moon could provide an ideal location for a manned lunar base, by providing shelter from various natural hazards, such as cosmic radiation, meteorites, micrometeoroids, and impact crater ejecta, and also providing a natural environmental control, with a nearly constant temperature, unlike that of the lunar surface showing extreme variation in its diurnal cycle. An analysis of radiation safety issues on lunar lava tubes has been performed by considering radiation from galactic cosmic rays (GCR) and Solar Particle Events (SPE) interacting with the lunar surface, modeled as a regolith layer and rock. The chemical composition has been chosen as typical of the lunar regions where the largest number of lava tube candidates are found. Particles have been transported all through the regolith and the rock, and received particles flux and doses have been calculated. The radiation safety of lunar lava tubes environments has been demonstrated.
A long-term goal of space exploration is the development of a lunar settlement that will not only be largely self-sufficient but also contribute to the economy of the Earth-Moon system. Proposals for lunar mining and materials processing developments, as well as tourism-based applications, have appeared in the literature for many years. However, so great are the technical and financial difficulties associated with sustained lunar development that, more than 30 years after the end of the Apollo programme, there have been no practical advances towards this goal. While this may soon be remedied by a series of proposed unmanned orbiters, landers and rovers, the philosophy of lunar exploration and development remains the same as it has for decades: conquer, exploit, and ignore the consequences. By contrasting the well-recognised problems of Earth orbital debris and the barely recognised issue of intentional spacecraft impacts on the lunar surface, this paper illustrates the need for a new model for lunar exploration and development. This new paradigm would assign a value to the lunar environment and provide a balance between protection and exploitation, creating, in effect, a philosophy of sustainable development for the Moon. It is suggested that this new philosophy should be an integral part of any future strategy for lunar colonisation.
The dynamics of how astronauts' immune systems respond to space flight have been studied extensively, but the complex process has not to date been thoroughly characterized, nor have the underlying principles of what causes the immune system to change in microgravity been fully determined. Statistically significant results regarding overall immunological effects in space have not yet been established due to the relatively limited amount of experimental data available, and are further complicated by the findings not showing systematically reproducible trends. Collecting in vivo data during flight without affecting the system being measured would increase understanding of the immune response process. The aims of this paper are to briefly review the current knowledge regarding how the immune system is altered in space flight; to present a group of candidate biomarkers that could be useful for in-flight monitoring and give an overview of the current methods used to measure these markers; and finally, to further establish the need and usefulness of incorporating real-time analytical techniques for in-flight assessment of astronaut health, emphasizing the potential application of MEMS/NEMS devices.
Why explore the universe. 30th aerospace sciences meeting & exhibit, Reno
- Rmcc Adams
Adams, RMcC. Why explore the universe. 30th aerospace sciences meeting & exhibit, Reno; January 6-9, 1992.
Is space exploration worth the cost? Space Rev
- D Livingston
Livingston D. Is space exploration worth the cost? Space Rev 2008.
More than the Moon. washingtontimes.com
- E Sterner