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

Lunar sun-synchronous roving is an affordable and promising manner of acquiring continuous power supply and warmth in robotic polar exploration. Sun-synchronous route planning is challenging to meet the spatiotemporal constraints of lunar topography and time-varying illumination. Moreover, in pursuit of spaceflight feasibility and safety, the safety-optimal planning method adapting to spatiotemporal maps remains to be addressed. This paper takes the first step to investigate this issue, in which the distribution of roving speed is considered a critical factor. Three-dimensional lunar spatiotemporal maps are constructed based on topography and illumination analysis. A spatiotemporal planning algorithm named MSST-A* is proposed, which takes a multi-speed node expansion mechanism, thus supporting speed distribution optimization. Afterward, route evaluation functions involving motion, energy, and integrated risk, together with the optimal heuristic function, are designed for safety-optimal planning. Two comparative tests are conducted, and results indicate that the proposed approach is practical and superior in terms of motion safety and energy reliability. Besides, an integrated-risk-minimal route circumnavigating the Shackleton Crater at the south pole in three lunar days is solved, demonstrating the existence of long-term lunar sun-synchronous routes with good engineering significance. • The paper is innovative in the following bullet points: • Safety-optimal lunar sun-synchronous route planning is firstly studied. • MSST-A* for optimizing the spatiotemporal distribution of speed is raised. • Polar sun-synchronous circumnavigating routes of fine safety are solved. • The existence of the sun-synchronous route of engineering reliability is proved. [ABSTRACT FROM AUTHOR]

With the deepening of space exploration, the moon has significant value for scientific research. However, because of such research's costs and risks, international cooperation will be critical for the future lunar exploration. In 2021, China and Russia jointly initiated the International Lunar Research Station (ILRS) project and released the Guide for Partnership (V1.0). However, the basic regulatory framework for creating the ILRS project is not yet in place, posing a challenge to pursuing this complex and technically ambitious endeavor. The paradigm of international cooperation that was the International Thermonuclear Experimental Reactor (ITER) project set a good example of how scientific research could transcend geographic boundaries. This paper examines the ITER Agreement, the constitutive agreement of the ITER, and analyzes the successful experience of large-scale international cooperation on a complex scientific project. Then, in view of the characteristics of the ILRS project and the existing space law, the main elements of a regulatory framework for international cooperation on this project are proposed, which follows the ITER Agreement closely. The paper concludes that such a regulatory framework for international cooperation on the ILRS project may contribute to the peaceful exploration and use of the moon, thus promoting the well-being and interests of humankind. • The moon has significant value for scientific research. • International cooperation will be critical for the future lunar exploration. • A regulatory framework for the International Lunar Research Station (ILRS) is not in place. • The paradigm of international cooperation on the ITER set a good example. • The main elements of a regulatory framework for the ILRS are proposed. [ABSTRACT FROM AUTHOR]

Martian Moons eXploration (MMX) is a mission under development in JAXA in cooperation with NASA, CNES, ESA, DLR to be launched in 2024. This paper introduces the result of its preliminary design and the latest status of the MMX program, putting more weight on the novel part of the mission. The goal of MMX is to reveal the origin of the Martian moons and then to make progress in our understanding of planetary system formation and of primordial material transport around the border between the inner- and the outer part of the early solar system. Additionally, the mission is to survey two Martian moons and return samples from Phobos. Add to those MMX's contribution to the planetary science field, on the growing discussion on the International Space Exploration activities, MMX's contribution to future human Mars exploration is also considered as an essential aspect of the program. Following the system definition study results presented in the previous conference, the following items will be reported in this paper. First, as a result of the comprehensive completion of the Phase-B activities, the preliminary design is completed in coordination with the design of the spacecraft system, mission instruments, and operation plans. This paper describes the proximity and surface operations around Phobos in detail. Second, Phase-C activities have started, incorporating engineering models manufacturing and tests. Those of critical technologies for surface exploration are described in detail. Moreover third, the programmatic aspects, including international cooperation frameworks and the program schedule, are presented. • Martian Moons eXploration (MMX) is a JAXA's mission to be launched in 2024. • MMX achieves the world's first sample return from a Martian moon, Phobos, in 2029. • MMX investigates the origin of Martian moons and the planetary formation process. • Sample of Phobos contains the ejecta derived from Mars by meteorite impacts. • MMX acquires data that contributes to future human Mars exploration. [ABSTRACT FROM AUTHOR]

Jordan's political stability has aided in the country's notable rapid growth these past few years, despite its limited natural and financial resources. Jordan is currently taking the lead in multiple sectors in the region, such as Education, Medicine, Information and Communications Technology, and more. The advancement of these industries has encouraged the progress and development of the Jordanian community as well. Similarly, space can contribute societal benefits in an emerging space country like Jordan. Under the Moon Village – Participation of Emerging Space Countries (MV-PESC) program, a roadmap for Jordan's contribution to lunar exploration and the Jordan Space Research Initiative (JSRI) were created. This 20-year roadmap focuses on establishing an analog R&D facility for Moon and Mars in the Jordanian desert of Wadi Rum, locally known as the Valley of the Moon. This roadmap aims to support the following building blocks: Water Resource Management, Renewable Energy, In-situ Resource Utilization (ISRU) and Robotics, Dust Mitigation, Agriculture, Smart City Infrastructure, and Women's Health. These building blocks will advance research required for the Moon Village, while simultaneously contributing to sustainable development in Jordan. Due to the national importance which Wadi Rum holds, for being a tourist attraction site, a naturally protected area, and a homeland for the local nomadic tribes (The Bedouins), community engagement is a crucial aspect of this roadmap. Finding an appropriate way of approaching the local community in Wadi Rum, the general public in Jordan, local authorities and the government, as well as fostering international cooperation in the space community, is crucial to its success. This paper investigates how the implementation of the Moon Village PESC project in Jordan, as embodied by JSRI, will contribute to solving some of its most pressing societal and economic issues, such as water scarcity, while highlighting how the incorporation of space technology and research will play a major role in advancing Jordan's existing research goals and initiatives. By linking the roadmap developed by JSRI to the preliminary Roadmap for Space and Sustainable Development (RSSD), which was introduced in a previous IAC paper titled "Jordan and the United Nations Space2030 Agenda: A Roadmap for Space and Sustainable Development" (2020), this paper also identifies ways in which the implementation of the Moon Village in Jordan will contribute to the achievement of the objectives of the UN Space2030 Agenda and the Sustainable Development Goals. - Countries with limited natural and financial resources must justify space exploration - Analog space research can contribute benefits to emerging space countries like Jordan - A roadmap for Jordan's participation in lunar exploration was created - This research focuses on bridging sustainable development with space research - Pursuing research in the selected areas will bring benefits to Jordanian society [ABSTRACT FROM AUTHOR]

As we continue exploration of the Lunar and Martian surfaces and push farther into unknown and unstructured environments, employing a team of distributed heterogeneous robots will increase the odds of success by enabling more complex task planning that utilizes the complementary capabilities and synergy of the team members. A requirement to reap these potential benefits is effective cooperation and collaboration between the members of a robot team. Defining a metric for effective cooperation is a difficult task that will depend on the composition of the team, the task to be performed, and the working environment. This paper establishes a method for determining the reward criteria (figures of merit) that can be used for training the robot swarm through reinforcement learning techniques. A hierarchical framework of rewards is used which, at the lowest level, measures the success of an individual robot in performing its task. The success of all robots performing different subtasks is then measured using the Quantified Cooperation Assessment (QCA) metric which was introduced in our previous research of multi-robot collaboration. Finally, the mission-level success and overall reward is determined by weighting each task using its priority within the overall mission context. A common reward for each of the robotic teammates is then applied within the learning process, which emphasizes group performance over that of an individual and encourages cooperative behavior. This cooperation framework is trained in a grid-based environment representing an exploration mission on a planetary surface by a heterogenous team of robots consisting of a landing craft, a traditional rover, and several small agile robots. The robots are trained concurrently, but with individual policies developed for each agent resulting in a decentralized control scheme. Once trained, the control policies were evaluated in several test environments consisting of novel terrain maps and regions of interest. An average success rate of 90 % was seen in the test environments demonstrating the robustness of the trained policies. The robots have been trained to not only complete the mission but also perform it in a cooperative manner as well as show the scalable and resilient behavior. • Robotic team trained to locate volatiles in a simulated planetary environment • Cooperation among team members assessed with a quantifiable metric • Success achieved in novel environments not used in training • Decentralized control provided robustness to adding and removing team members [ABSTRACT FROM AUTHOR]

The establishment of secure earth-independent long-term lunar habitats has been envisioned by numerous government agencies and private companies. Recent advancements in assessing seismic hazards caused by shallow moonquakes have highlighted the importance of incorporating this phenomenon into the design of robust and resilient lunar structures. However, further research is required to explore lunar habitat design that considers seismic loads. This paper proposes assessing the structural response of a lunar habitat made of sulfur concrete covered with a regolith layer. The numerical model of the structure is subjected to gravitational, internal pressure and seismic loads. The seismic analysis of the structure is carried out using spectral and nonlinear time history methods. Conditional mean spectra for shallow moonquakes with return periods of 75, 475, 970 and 2475 years are used in the seismic analysis. The records used for the temporal analyses were ground motions that agree with a preliminary seismic hazard on the Moon. The results of temporal analyses reveal that shallow moonquakes with return periods greater than 475 years can lead to the loss of the global stability of the structure. Consequently, the findings imply that seismic loads have the potential to impose unacceptable demands on lunar structures constructed from in-situ materials like sulfur concrete. Hence, it is imperative to incorporate seismic considerations in the design process for developing resilient and long-term lunar habitats. • Seismic analysis of a lunar structure was carried out using spectral and temporal methods. • A methodology was adapted to scale moonquake records to different hazard spectra obtained from probabilistic methods. • It was demonstrated that seismic demand might generate unacceptable deformations in lunar structures built with in-situ materials. [ABSTRACT FROM AUTHOR]

The success of a multi-kilometre drive by a solar-powered rover at the lunar south pole depends upon careful planning in space and time due to highly dynamic solar illumination conditions. An additional challenge is that the rover may be subject to random faults that can temporarily delay long-range traverses. The majority of existing global spatiotemporal planners assume a deterministic rover-environment model and do not account for random faults. In this paper, we consider a random fault profile with a known, average spatial fault rate. We introduce a methodology to compute recovery policies that maximize the probability of survival of a solar-powered rover from different start states. A recovery policy defines a set of recourse actions to reach a safe location with sufficient battery energy remaining, given the local solar illumination conditions. We solve a stochastic reach-avoid problem using dynamic programming to find an optimal recovery policy. Our focus, in part, is on the implications of state space discretization, which is required in practical implementations. We propose a modified dynamic programming algorithm that conservatively accounts for approximation errors. To demonstrate the benefits of our approach, we compare against existing methods in scenarios where a solar-powered rover seeks to safely exit from permanently shadowed regions in the Cabeus area at the lunar south pole. We also highlight the relevance of our methodology for mission formulation and trade safety analysis by comparing different rover mobility models in simulated recovery drives from the LCROSS impact region. • The safety of a solar-powered rover depends on its location, energy and time of day. • Maximally safe behaviours depend on when and where delays occur during a traverse. • The probability of survival of a rover varies non-monotonically with time. • Min–max dynamic programming can conservatively account for the temporal risk ambiguity. [ABSTRACT FROM AUTHOR]

Obtaining planetary soil samples and returning them to the Earth is the most effective solution to detect the distribution and reserves of planetary resources. In order to maintain the stratification and a high coring ratio of soil samples during the sampling process, China National Space Administration adopted a flexible tube coring (FTC) method for the upcoming Chang'e-6 mission. In this paper, the lunar regolith FTC characteristics, coupled with its spiral debris discharge were modeled. Orthogonal experiments were carried out with different drilling parameters using the prepared high-density lunar regolith simulant. The results show that the coring height and coring ratio are greatly determined by the penetration per revolution (P P R) index. The lunar regolith simulant's coring ratio was as high as 90% when the P P R was optimized. The physical and mechanical parameters of artificial lunar regolith were characterized with respect to the P P R index as well as the dynamic flowing of the internal core, with a resulting accurately tuned coring ratio prediction model. Furthermore, the drilling load analysis can be applied to the optimization of drilling parameters employed by Chang'e-6 when collecting lunar regolith. • FTC method analysis to maintain the information of lunar regolith bedding. • Modeling and test methods for coring ground flow characteristics. • Analysis of core disturbance due to shear dilation under flow field coupling. • PPR has significant influence on coring height and ratio. [ABSTRACT FROM AUTHOR]

The Martian Moons eXploration (MMX) mission by the Japan Aerospace Exploration Agency, JAXA, will explore the Martian moons Phobos and Deimos. In addition to investigating the moons remotely and returning samples from Phobos, MMX will also deliver a small (about 25 kg) Rover to the surface of Phobos. The payload of the Rover consists of four scientific instruments: RAX, a Raman spectrometer to measure signatures of the mineralogical composition of the surface material, NavCam, a stereo pair of cameras to investigate the terrain and allow for navigation, miniRAD a radiometer to measure the surface brightness temperature of both, regolith and rocks, and two WheelCams which will observe the wheel-surface interface, and thus investigate the properties and dynamics of the regolith. The cameras, will serve both, technological and scientific needs. The rover will be deployed during the rehearsal phase of the landing operations for the main spacecraft and will thus land in proximity to the first sampling area. During its operational lifetime on Phobos (about 100 days), the in-situ measurements performed with the rover payload will provide scientific context for the returned samples, provide ground truth, study the surface heterogeneity and obtain information on the physical properties of undisturbed surface material. The MMX launch is planned for September 2024 and the Rover delivery is scheduled for 2027. The Rover is a contribution by the Centre National d'Etudes Spatiales (CNES) and the German erospace Center (DLR) with additional contributions from INTA (Spain) and JAXA. • In this paper we give an overview of the rover, which will be part of the MMX mission to Phobos. • The MMX rover will explore the surface of Phobos with cameras, a Raman spectrometer and a radiometer. • Scientific objectives and the mission outline are discussed. [ABSTRACT FROM AUTHOR]

MIRS is part of the French contribution to the Martian Moons eXploration (MMX) mission that will be launched in 2024 by the Japan Aerospace Exploration Agency (JAXA). It is a near-infrared imaging spectrometer developed by the French Laboratory of Space Studies and Astrophysics Instrumentation (LESIA), of the Observatoire de Paris – PSL , with close cooperation and financial support from CNES. One of the major mission goals is to understand the origin of Phobos and Deimos, providing important insights into planetary formation and the transfer of matter in the region connecting the inner and outer solar system. During the four years of the mission, the MIRS control centre will provide precise sequencing of MIRS activities and guidance of its line of sight, with two main drivers: optimize scientific return and comply with the operability constraints of the instrument, the satellite and the system. In this perspective, observation strategies are designed, modelled and tested iteratively throughout all preparation phases of the mission. Discussions on concrete simulation results and illustrations improve mutual understanding, raise unexpressed needs and constraints and promote feedback on the efficiency of the proposed strategies. They also favour a global optimization of the entire system with the refinement of the trajectories and of the scheduling considering the seasons of the Martian system. This paper describes the whole process of observation strategies development in cooperation with the MMX and MIRS system and scientific teams, as well as the current status and results. • Observation strategies elaboration process from design to operations is presented. • It involves a continuous and close cooperation with the Scientific and System teams. • It defines precisely How and When to perform observations. • Optimization algorithms are implemented to solve scheduling combinatorial problems. • Continuous validation and performances assessment allow to refine the design. [ABSTRACT FROM AUTHOR]

Global Navigation Satellite Systems (GNSS) are not only used in terrestrial applications, but also in Low-Earth orbit satellites and in higher altitude missions. NASA's Magnetospheric Multiscale (MMS) mission has demonstrated the capabilities of existing GNSS systems to provide positioning, navigation, and timing (PNT) services in the Cis-lunar space. The resurgence in plans by national space agencies for Lunar exploration presents a need for accurate, precise, and reliable navigation systems to ensure the safety and success of future missions. Moreover, the increased amount of Moon missions over recent years, shows the requirement of navigation capabilities for Low Lunar orbiters, Moon landers, Moon rovers, and manned missions. The success of Global Navigation Satellite Systems (GNSS) on Earth, presents an opportunity for the study of a potential design requirements and expected performance of a Lunar GNSS constellation. We have approached this problem through the methodology of multi-objective optimization; numerically simulating the orbits, and using the Position Dilution of Precision (PDoP) as the figure of merit to optimize a set of 200 constellation designs and improving them gradually over 1864 generations. Over 12,000 unique constellation designs were generated with the best 10 constellations presented in this paper for consideration and further study. Compared to the literature, these 10 constellations achieved a 44% improvement in PDoP (2.73) using the same number of satellites in each constellation, and meeting the performance requirements of planned Lunar missions. • There is an increase of Moon missions over the recent years • These missions will require reliable navigation systems to ensure their success • Earth GNSS systems can provide position, navigation, and timing in the Cislunar space • Augmentation satellite systems will be required to improve PNT accuracy on the Moon • Multi-objective optimization has been used to optimize satellite constellation design • This methodology can also be used to optimize a Lunar GNSS constellation design [ABSTRACT FROM AUTHOR]

Future human space exploration missions are planned to take humans into permanently shaded regions (PSRs) at the lunar south pole. These areas are among the coldest places in the Solar System and represent a novel operational environment for spacesuits. In addition to this technical challenge, there is scientific interest in volatiles that are cold trapped in PSRs. This paper presents results from several simulations performed to assess the effect of the thermal interactions between the lunar surface and a comparatively warm spacesuit in a permanently shadowed crater on the Moon. After the tools used to perform the simulations and their limitations are discussed, two scenarios are introduced: a crater scenario to investigate the extent and magnitude of the thermal influence of the spacesuit in realistic setting, and a flat plane scenario that is used to analyze the effect of different astronaut translation speeds on the surface temperature changes. While the results show a significant change in lunar surface temperature of up to 60 K within 1.5 m of the astronaut, the effective sink temperature for the spacesuit only changes by a few degrees Kelvin, which is not large enough to have any implications on the design of the spacesuit system. Due to the low thermal conductivity of the lunar regolith and radiation being the dominant mode of heat transfer, the surface temperature increase is only significant for very slow translation rates or periods during which the crewmember remains stationary. The absolute temperature increase can be large enough to release volatiles from their entrapment, which in turn may necessitate a spacesuit design that radiates less heat to protect science objectives. However, further research and experimentation is necessary to determine which species are most susceptible in specific surface compositions and at which temperatures. • Dynamic thermal simulations of a spacesuit in a permanently shadowed lunar crater. • The effects of astronaut translation speed are presented. • The presence of an astronaut causes a significant increase in surface temperature. • The effective sink temperature for the spacesuit changes insignificantly. [ABSTRACT FROM AUTHOR]

The design of a permanent human habitat on a planetary body other than the Earth is an idea introduced many decades ago, which became even more significant after the landing of the first humans on the Moon with the Apollo missions. Today's rampant technological advances combined with ambitious missions, such as the Insight mission on Mars and the Artemis program for the Moon, render the vision of space colonization more realistic than ever, as it constantly gains momentum. There is a considerable number of publications across several disciplines pertaining to the exploration of Lunar and Martian environments, to those planets' soil properties, and to the design of the first habitable modules. The scope of this paper is to present a meticulous selection of the most significant publications within the scientific areas related to: (a) geotechnical engineering aspects, including the mechanical properties and chemical composition of Lunar and Martian regolith samples and simulants, along with elements of anchoring and rigid pads as potential forms of foundation; (b) ground motions generated by different types of Moonquakes and meteoroid impacts; (c) the different concepts and types of extraterrestrial (ET) structures (generic, inflatable, deployable, 3D-printed), as well as overall views of proposed ET habitats. Apart from the details given in the main text of this paper, a targeted effort was made to summarize and compile most of this information in representative tables and present it in chronological order, so as to showcase the evolution of human thinking as regards ET structures. • Design of a permanent human habitat. •Exploration of Lunar and Martian environments. •Mechanical properties and chemical composition of Lunar and Martian regolith. •Ground motions generated by moonquakes and meteoroid impacts. •Types of extraterrestrial structures (generic, inflatable, deployable, 3D-printed). [ABSTRACT FROM AUTHOR]

Networked robots will play an important role in lunar exploration. Communication is key to enable cooperation among robots for information sharing, and to remotely control robots with lower degree of autonomy from a lander or habitat. Operators and scientists must be able to make sound decisions on communication availability before or during sending robots to regions of interest for exploration. In this work we have a closer look at the communication coverage prediction for lunar exploration. We present an interdisciplinary and modular framework, which exploits terrain information to predict the data rate for exploring robots. Additionally, we create intuitively usable coverage maps for operators and scientists, and show how connectivity can be improved in unstructured environments by using a relay rover. This paper provides an overview of this framework, details on individual framework components, and simulation results for two exemplary exploration scenarios. • Wireless communication is key for cooperating and remote-controlled robots. • Communication coverage is limited caused by signal blockage due to the terrain. • A framework predicting communication coverage for networked robots is implemented. • Radio propagation models are taken into account. • Intuitively usable maps to make sound decisions by operators are created. • A communication relay can greatly enhance communication link availability. [ABSTRACT FROM AUTHOR]

The Earth-Moon system is constantly bombarded by meteoroids of different size and impact speed. Observation of the impacts on the Moon can enable thorough characterization of the Lunar meteoroid flux, which is similar to that of the Earth. While Earth-based Lunar observations are restricted by weather, geometric and illumination conditions, a Lunar-based observation campaign can improve the detection rate and, when observing the Lunar far side, complement in both space and time the observations taken from Earth. The Lunar Meteoroid Impact Observer (LUMIO), one of the two winning concepts of the ESA SysNova Lunar CubeSats for Exploration challenge, is a mission designed to observe, quantify, and characterize the micro-meteoroid impacts on the Lunar far side. It is based on a 12U CubeSat that carries the LUMIO-Cam, a custom-designed optical instrument capable of detecting light flashes in the visible spectrum. The spacecraft is placed on a halo orbit about the Earth–Moon L2 point, where permanent full-disk observation of the Lunar far side can be performed with excellent quality, given the absence of Earth background noise. After passing Phase 0 and an independent feasibility study in the ESA Concurrent Design Facility, the mission has successfully completed its Phase A in March 2021. Although the Phase 0 design of the LUMIO spacecraft was assessed as feasible by the ESA CDF study, a number of critical issues were identified, which have been tackled by the Phase A design. The paper presents the outcome of this Phase A design effort for the LUMIO spacecraft. Particularly relevant changes or updates in the spacecraft design include: a consolidated design of the LUMIO-Cam, with longer baffle for straylight protection; a set of ADCS sensors and actuators with increased redundancy; a combination of Direct-to-Earth communication and inter-satellite link with a mothership in Lunar orbit; use of Earth ranging to complement and validate the current innovative autonomous navigation strategy based on optical observations of the Moon by means of the LUMIO-Cam; re-assessment of the COTS components selection for the power and propulsion systems. • Description of the LUMIO mission and its scientific relevance. • Evolution of the LUMIO spacecraft design from pre-Phase 0 to Phase A. • Detailed description of the current design choices for all sub-systems of the LUMIO spacecraft. • Complete, detailed mass budget of the LUMIO spacecraft. [ABSTRACT FROM AUTHOR]

This paper studies the design of a deployable structure, with a background on scientific balloons, in order to simulate a future habitat station for human exploration on the moon. Super Pressure Balloons were considered because of their high resistant to internal pressure due to its lobed shape. This design analysis considers the Lobed pumpkin with lobed cylinder shape for the finite element stress analysis. The produced forms were transformed into structural models in Karamba (Finite Element Analysis) Plugin. Some limitations such as support points, loads, cross-section, and material have been determined for analyzing the stress behaviour of the membrane for the Moon Habitat. Two different shapes are analyzed from a different starting surface and mesh, a relationship between different deployment shape will be compared according to the FE analysis results. The analysis result focuses on the way a designer can interact with the search computational procedure, driving it towards the desired solution. We made a potential sizing assumption regarding the fairing size; we choose SpaceX Falcon Heavy because it has the largest payload fairing internal volume. • Deployable structures based on SPB are highly resistant to internal pressure. • We can increase the volume of SPB without increasing the diameter of balloon. • The force acting on the entire load ropes, proportional to the cross-sectional area, never increase.The high tensile stress resistant design of SPB design makes it a potential candidate for space habitats. • The high tensile stress resistant design of SPB design makes it a potential candidate for space habitats. [ABSTRACT FROM AUTHOR]

Geodetic and geophysical investigations of the Galilean moon Callisto address fundamental questions regarding the formation and evolution of the Jovian system. Callisto's evolution and internal structure appear to significantly differ from the other Jovian satellites. Similarly-sized Ganymede is a highly evolved ice-rock moon with a differentiated interior, intrinsic magnetic field, and abundant surface evidence of internal activity. In contrast, Callisto's surface is ancient, and Galileo spacecraft data suggest its interior is only incompletely differentiated, despite the presumed presence of a sub-surface ocean. These properties make Callisto uniquely able to constrain the timing and nature of the Jovian system formation. The Magnetics, Altimetry, Gravity, and Imaging of Callisto (MAGIC) mission concept is conceived to fully characterize the properties of this enigmatic moon from its deep interior to the icy shell. Three main instruments are included as a scientific payload. Highly accurate measurements of Callisto's topography, magnetic field, and morphology are obtained by the onboard laser altimeter, magnetometer, and camera, respectively. The telecommunication system supports an additional gravity and radio science investigation. Long- and short-wavelength gravity anomalies afford powerful constraints on internal differentiation and the properties of the hydrosphere (water and ice). Comprehensive numerical simulations and covariance analyses of MAGIC mission scenarios presented in this paper show that the gravitational degree-2 normalized coefficients and the pole obliquity enable the determination of the moment of inertia with an accuracy better than 0.015%. The combination of gravity and altimetry measurements acquired by MAGIC are essential to the characterization of Callisto's interior if – as is likely – the degree-2 gravity includes non-hydrostatic terms. MAGIC's radio science data yield the estimation of Callisto's gravity field with spatial resolutions of <100 km. The combination of gravitational and deformation tides that are retrieved by the radio science and altimetry investigations, respectively, leads to the recovery of the rigid ice shell thickness to within ∼3 km. Together these datasets would resolve ambiguities inherent in Galileo flyby data, revealing Callisto's interior structure as well as the existence and properties of its postulated internal ocean. • MAGIC is a medium-class mission concept to explore the Jovian moon Callisto. • The science payload is designed for a comprehensive geophysical investigation. • Highly accurate gravity measurements will be acquired from a low-altitude orbit. • A thorough estimation of Callisto's moment of inertia will reveal its interior. • Gravitational and deformation tides will help to constrain the ice/ocean properties. [ABSTRACT FROM AUTHOR]

Lunar Space exploration is currently accelerating, and manned and unmanned missions to the Moon are planned by several space agencies and private companies in the coming 5–10 years. The construction of the Lunar Orbital Platform Gateway (LOP-G) and plans to establish a more permanent human presence on the Lunar surface will increase the landing frequency and require the capability to safely soft-land successive missions in near proximity to each other. The lunar South Pole is one of the preferred locations for surface exploration due to the discovery of volatiles in the permanently shadowed craters at the poles. However, landing on the lunar South Pole of the Moon is challenging due to the illumination and loss of Earth line-of-sight conditions combined with complex topography. The increased interest in co-located lunar landings concurrent with construction of lunar infrastructure and a challenging landing area warrants new approaches in navigation technology. In this paper we present a concept for a system of radio beacons installed around the Shackleton crater rim "SR1" landing site on the lunar South Pole. We present considerations for optimal placement of the radio beacons based on the specific landing site topography and quantify our finding with dilution of precision (DOP) calculations. We present a novel method for deploying the radio beacons as penetrators with embedded thermoelectric generators (TEGs) for autonomous power generation. We present findings on beacon survivability, penetration depth, spin-stabilization of the penetrators and maximal theoretical power generation. • In-Situ navigation infrastructure for co-located, pin-point lunar landings. • Optimal placement and geometry of surface radio beacons using Dilution of Precision (DOP) analysis. • Deploying radio beacons as penetrators for fast installation and long-duration operation. • Autonomous power generation in penetrator beacons using thermoelectric generators. • Multiple Beacons for Lunar Powered Descent and Landing. [ABSTRACT FROM AUTHOR]

Recent remote sensing results and the current Artemis lunar exploration program have heightened interest in the potential for producing propellant on the lunar surface to contribute to the sustainability of ongoing activity in cislunar space. In this paper, we examine the case of lunar propellant competing against Earth-sourced propellant both on the lunar surface and in low lunar orbit. We restrict ourselves to providing lunar propellant for the purpose of landing cargo from low lunar orbit onto the lunar surface. In our analysis, we derive the revenue recoverable from, or value delivered by, lunar propellant by matching the cost of landing cargo using Earth-sourced propellant, rather than the cost of transporting propellant from Earth. We present the arguments in commercial and non-commercial contexts. We find that there are opportunities on the lunar surface for extracting value above the competing propellant transportation cost from Earth. When competing against Earth-sourced propellants in low lunar orbit, there are opportunities to extract more value than one could by supplying commodity propellants. The opportunities arise from expanding the factors contributing to competing costs, using combined cargo and propellant concepts of operations that deliver higher propellant efficiency, and from consolidating transportation assets with propellant supply to achieve higher capital efficiency. By using this analytical approach to transportation and transportation support services we were able to lower the barriers to the production and use of lunar sourced propellant. • Transport cost as a price proxy misses opportunities to charge more for propellant. • Integrated propellant supply & transport services can charge more. • One can charge more for lunar sourced ascent propellant than the cost of landing it. • Transport services using lunar sourced propellant do not need orbital depots. • Integrated services can bridge part of the lunar propellant viability gap. [ABSTRACT FROM AUTHOR]

Considerable attention has been paid to the exploration of moon, especially the construction of lunar habitat. However, few studies are found working on the construction equipment being suitable for trans planetary transportation, assembly, and working in lunar environment. This paper proposed a novel cable-driven printer used to build lunar architecture. The pose measurement and control strategy of the printing system is proposed. To study the reconfiguration characteristic of the cable-driven printer, several trees with arbitrary locations were selected as the rack to reconstruct the system outdoors. The key factors such as the sensitivity of pose deviation to system parameters affecting the reconstruction performance is discussed. The forming space of the cable-driven printer is analyzed theoretically and the forming ability of the system is verified experimentally. It is found that the cable-driven printer has the advantages of simple structure, small weight, large forming space and good reconfiguration characteristic, which shows the great potential of the proposed cable-driven printer in the construction of lunar architecture. • We present a novel cable-driven printer for lunar architecture. • The printer can be easily reconstructed on randomly selected lunar terrain. • The printer has a large ratio of forming space to mass. • We proposed the measurement and control strategy of the printer. • The printer has a flexible printing posture thanks to a 6-DOF actuator. [ABSTRACT FROM AUTHOR]

Dust hazards are considered to be one of the technical challenges for future lunar exploration. In our past work a new dust mitigation technology was introduced utilizing an electron beam to remove dust particles from various surfaces. This technology was developed based on a patched charge model, which shows that the emission and re-absorption of electron beam induced secondary electrons inside microcavities between dust particles can lead to sufficiently large charges on the dust particles, causing their release from the surface due to strong repulsive forces. In this paper an improvement in the effectiveness of this technology is demonstrated with varying the beam incident angle on dust-covered sample surfaces by rotating the samples relative to the beam. Due to random arrangements of the microcavities, more of them will be exposed to the beam with various incident angles, thereby causing more dust release from the surface. The cleaning performance is tested against three samples: glass, spacesuit, and a photovoltaic (PV) panel. Lunar simulant (<25 μm in diameter) is deposited onto the sample surfaces such that the initial cleanliness of the samples is 0 % (full dust coverage) and 40 %. Varying the beam incident angle shows an overall surface cleanliness increase of 10–20 % in addition to the cleanliness achieved with a fixed beam angle. The ultimate cleanliness reaches 83–92 % for the glass and spacesuit samples. The PV panel coated with MgF 2 is shown to be more adhesive to the dust with the maximum cleanliness of 50–63 %. • The e-beam dust mitigation technology is improved by varying the beam incident angle. • Beam exposure of more microcavities causes additional dust to come off the surface. • The cleaning effectiveness is enhanced by 10–20 % compared to using a stationary beam. [ABSTRACT FROM AUTHOR]

Quasi-satellite or distant retrograde orbits are stable orbits in the restricted three-body problem will be used in remote planetary satellite missions like JAXA's Martian Moons eXploration (MMX). Due to Phobos' irregular gravity field, the proximity operations of the MMX mission require sophisticated techniques for transfers and maintenance between different quasi-satellite orbits. This paper focuses on the design of transfer trajectories between Quasi-Satellite Orbits (QSO) around Phobos. We utilize horizontal bifurcated Multi-Revolution Periodic QSOs (MP-QSOs) that are found in the vicinity of an ellipsoidal Phobos under the assumptions of the circular Hill Problem. Transfer strategy via MP-QSOs is explored through transfer maps that illustrate transfer design space between different altitudes QSOs. It is found that transfers via MP-QSOs provide insights on minimum Δ V transfers and the parameters determining the transfer cost. The proposed transfer method is explicitly applied to MMX baseline QSOs. This research has identified that transfers between high(100 × 200 km)-to-mid(50 × 100 km), mid-to-low(30 × 50 km), and lower altitude(< 30 km) QSOs via MP-QSOs can be achieved with as low as 11.63 m/s, 3.99 m/s, 1.74 m/s, and 0.97 m/s, respectively. • Martian Moons eXploration mission considers QSOs to explore Phobos. • Bifurcated QSO families are explored for transfer design between QSOs around Phobos. • Δ V of the transfer is defined by geometrical parameters that minimize transfer costs. • 2D Transfer maps are introduced to visualize the design domain between QSOs. • Transfer maps provide a basis for optimizing retrograde transfer trajectories. [ABSTRACT FROM AUTHOR]

A renewed interest in lunar exploration with the focus on establishing a constant human presence on the Moon calls for developing new lunar human landing systems (HLS) which would deliver the crew from the prospective Lunar Gateway station to the surface of the Moon and back. Over the years, different human lunar lander architectures were proposed and multiple architecture studies were performed. However, those studies are relevant to the specific assumptions and lunar architectures proposed at the time of conducting the study. Since the current vision for lunar exploration includes new features, such as having the Lunar Gateway and switching to reusable systems, there is a need for a new HLS architecture study. Such studies are being performed by private companies; however, those are rarely publicly available. The goal of this paper is to address this gap and provide a publicly available architectural analysis within the current views on the future human lunar exploration. We assume the Lunar Gateway in an L2 near rectilinear halo orbit and a landing site at the lunar South Pole; the number of HLS crew of 4; the surface stay time of ~7 days, the payload mass delivered to the surface of 500 kg, and the payload mass returned from the surface of 250 kg. A set of parametric models including an HLS model and an HLS program cost model is developed for the analysis. 39 architectures with varying number of stages (1, 2, and 3 stages) and propellant combinations (LOX/LH2, LOX/CH4, and MMH/NTO) are explored. The Pareto analysis shows that there is a difference between typical performance trends for expendable and reusable architectures. For expendable architectures, the 2-stage option seems to be the most advantageous while, for reusable architectures, the 1- and 3-stage options are either comparable or win over the 2-stage option even for the number of system uses as low as 3. In terms of the propellant combinations, pure LOX/LH2 or combined LOX/LH2/LOX/CH4 architectures dominate the tradespace. Assuming that the inter-stage propellant compatibility is a preferred option for systems refueling from the Gateway, 1-stage and 3-stage all LOX/LH2 architectures are identified as the likeliest candidates to have lowest HLS-related production and launch costs. Further cost analysis of those two architectures shows that the 1-stage HLS wins over the 3-stage system in terms of the overall HLS program cost if a long-term exploration program (on the order of tens of missions) is assumed. • We present parametric models evaluating human landing systems for lunar exploration. • The proposed models account for system reusability and key architectural decisions. • We propose an integrated technical and cost analysis of landing system architectures. • We discuss engineering tradeoffs in competing human landing system designs. • We identify the 1-stage LOX/LH2 system architecture as a preferred design baseline. [ABSTRACT FROM AUTHOR]

The paper deals with key problems related to the initial stage of the Moon exploration in the coming decades. Moon exploration plans are on the agenda of the world's leading powers. Some important issues linked to of the Lunar Base development and the pre-construction studies on the selection of the most suitable regions for the purpose and along with their natural properties are discussed. We consider a scenario in which robots are widely used for further study and exploration of the Moon. The plan includes developing a global geological and geophysical reference network on the lunar surface and use mobile equipment equipped with drilling rigs. Such means (lunar rovers of a new generation) are in demand for the preliminary selection of the most suitable places for the Lunar Base construction as an initial element of the complex lunar infrastructure. Two types of lunar rovers are considered in detail: the prospecting and exploration lunokhod of the middle class "Geologist-Explorer" and the heavy lunokhod "Robot-Geologist". They are intended to carry out regional geological, geochemical and geophysical surveying, sampling, analysis and comparison of data on the natural conditions of selected areas on promising routes with a radius of up to 500 km on the Near and Far side of the Moon. An important goal is data collection on the availability of such important local resources as water ice, frozen volatile and ore deposits. The issues of safety of humans stay in harsh conditions on the lunar surface and the possibility of protection from external factors are discussed, which plays an important role in the implementation of plans for the future lunar exploration. [ABSTRACT FROM AUTHOR]

Currently, several polar explorations of the Moon are planned, because it has been suggested that water ice might be present in the lunar polar region based on remote sensing observation of the lunar surface using a neutron spectrometer and visible to infrared spectrometer. However, the precise amount and state of the water ice are still unknown. At the Japan Aerospace Exploration Agency (JAXA), we are also studying exploration of the lunar surface for resources, especially cold-trapped volatile such as water ice using a rover. Volatile materials are expected to be useful for future human activity on the Moon and there is strong interest in the origin and concentration mechanism of the water ice. Additionally, the polar regions are among the best candidates for long-term activity because of their long sunlight duration. To realize the mission, we are currently developing various technologies peculiar to exploration of lunar polar regions. This paper details the present status of the Japanese Lunar Polar Exploration Mission. • Volatile materials are expected to be useful as resources for activity on the Moon. • The Japan Aerospace Exploration Agency (JAXA) is studying on lunar polar mission. • This is a joint study with the Indian Space Research Organisation (ISRO). • ISRO and JAXA held the joint mission definition review in December 2018. • JAXA is developing technologies peculiar to exploration of lunar polar regions. [ABSTRACT FROM AUTHOR]

JPL is developing the Lunar Flashlight (LF) CubeSat mission, a 6U 14 kg spacecraft whose objective is to demonstrate new technology and measure potential surface water ice deposits in the permanently shadowed region (PSR) of the moon in preparation of future possible human lunar exploration. This mission will become the first interplanetary CubeSat to orbit the Moon. It uses a new green propulsion system as well as an instrument with spectrally tuned IR laser technology to search for volatiles in a specific region of the moon. The Guidance, Navigation and Control (GNC) system is crucial for delivering the spacecraft from Earth into Lunar orbit and supporting scientific measurements. Due to the challenging lunar orbit insertion and high tip off rate out of launch vehicle's dispenser, the initial design concept using solar sail propulsion accompanied with small commercial-on-the-shelf (COTS) reaction wheels was abandoned mid-course and replaced by a green propulsion system along with larger reaction wheels, both newly developed for LF. However, using thrusters for the small CubeSat created an additional challenge of controlling the spacecraft attitude. The story of the GNC system development, qualifications, technical challenges encountered, and lessons learned are discussed in this paper. • A CubeSat to search potential water in preparation of future human lunar exploration is developed. • The challenging GNC system development history and final result are described in this article. • Technology enhancements such as reaction wheel, green propulsion, and ephemeris are showcased. [ABSTRACT FROM AUTHOR]

This paper discusses a landing response control system based on the momentum exchange principle for planetary exploration spacecraft. In the past, landing gear systems with cantilever designs that incorporate honeycomb materials to dissipate shock energy through plastic deformation have been used, but once tested before launch, the system cannot be used in a real mission. The sky crane system used for the Mars Science Laboratory by NASA can achieve a safe and precise landing, but it is highly complex. This paper introduces a momentum exchange impact damper (MEID) that absorbs the controlled object׳s momentum with extra masses called damper masses. The MEID is reusable, which makes it easy to ensure the landing gear׳s reliability. In this system, only passive elements such as springs are needed. A single-axis (SA) model has already been used to verify the effectiveness of MEIDs through simulations and experiments measuring the rebound height of the spacecraft. However, the SA model cannot address the rotational motion and tipping of the spacecraft. This paper presents a two-landing-gear-system (TLGS) model in which multiple MEIDs are equipped for two-dimensional analysis. Unlike in the authors׳ previous studies, in this study each MEID is launched when the corresponding landing gear lands and the MEIDs do not contain active actuators. This mechanism can be used to realize advanced control specifications, and it is simply compared with previous mechanisms including actuators, in which all of the MEIDs are launched simultaneously. If each MEID works when the corresponding gear lands, the rebound height of each gear can be minimized, and tipping can be prevented, as demonstrated by the results of our simulations. [ABSTRACT FROM AUTHOR]

The photovoltaic lunar dust removal technology has proved to own potential application for future space exploration. In this new technology, based on the high voltage characteristics of the photoelectric material lanthanum-modified lead zirconate titanate (PLZT), a dust-removing electrode is used to polarize and remove the lunar dust. The influence of the area and the shape of the dust-removing electrode on the dust removal performance is analyzed in this paper. An optimization of dust-removing electrode design method is proposed and comb-shaped electrodes are designed to improve the dust mitigation efficiency of the system. The configuration of the comb-shaped electrode is optimized by theoretical analysis. A series of experiments are performed to reveal the influence of different factors, such as electrode area, electrode shape, light intensity, copper foil thickness, insulation film and geometric parameters of electrode, etc. on the dust removal performance. Research results of this work can serve as guidelines for optimization electrode design to maximize the efficiency of this photovoltaic lunar dust removal system for future lunar exploration. • A new photoelectric lunar dust removal technique is proposed. • An optimization dust-removing electrode design method is presented. • Electric field intensity distribution of the dust-removing electrode is obtained. • Dust removal efficiency is improved by approximately 100% with this method. [ABSTRACT FROM AUTHOR]

Abstract: What is it about the Moon that captures the fancy of humankind? A silvery disk hanging in the night sky, it conjures up images of romance and magic. It has been counted upon to foreshadow important events, both of good and ill, and its phases for eons served humanity as its most accurate measure of time. This paper discusses the Moon as a target for human exploration and eventual settlement. This paper will explore the more than 50-year efforts to reach the Moon, succeeding with space probes and humans in Project Apollo in the 1960s and early 1970s. It will then discuss the rationales for spaceflight, suggesting that human space exploration is one of the least compelling of all that might be offered. The paper will then discuss efforts to make the Moon a second home, including post-Apollo planning, the Space Exploration Initiative, and problems and opportunities in the 2004 Vision for Space Exploration, and cancellation of that program in 2010. [Copyright &y& Elsevier]

NASA planning for the human space flight frontier is coming into alignment with the goals of other planetary-capable national space agencies and independent commercial actors. US Space Policy Directive 1 made this shift explicit: "the United States will lead the return of humans to the Moon for long-term exploration and utilization". The stage is now set for public and private American investment in a wide range of lunar activities. Assumptions about Moon base architectures and operations are likely to drive the invention of requirements that will in turn govern development of systems, commercial-services purchase agreements, and priorities for technology investment. Yet some fundamental architecture-shaping lessons already captured in the literature are not clearly being used as drivers, and remain absent from typical treatments of lunar base concepts. A prime example is general failure to recognize that most of the time (i.e., before and between intermittent human occupancy), a Moon base must be robotic: most of the activity, most of the time, must be implemented by robot agents rather than astronauts. This paper reviews key findings of a seminal robotic-base design-operations analysis commissioned by NASA in 1989. It discusses implications of these lessons for today's Moon Village and SPD-1 paradigms: exploration by multiple actors; public-private partnership development and operations; cislunar infrastructure; production-quantity exploitation of volatile resources near the poles to bootstrap further space activities; autonomy capability that was frontier in 1989 but now routine within terrestrial industry. It outlines new work underway to close these gaps; and articulates conclusions that can guide future work. • Most of the time, most of a Moon base is robotic. • Base elements designed for robotic operations challenge conventional concepts. • Hierarchical supervisory control is essential. Full autonomy is not. • All known base functions can be emplaced completely robotically. • A habitable, oxygen-producing base can be constructed in less than four years of quarterly flights. [ABSTRACT FROM AUTHOR]

Abstract Returning to the Moon has kept gaining interest lately in the scientific community as a mandatory step for answering a cohort of key scientific questions. This paper presents a novel Lunar mission design to demonstrate enabling technologies for deep-space exploration, in accordance with the Global Exploration Roadmap and the National Research Council. This mission, named ALCIDES, takes advantage of some of the systems that are currently under development as a part of the HERACLES exploration architecture: these include the Orion module, the Space Exploration Vehicle, the Boeing Reusable Lander, the Ariane 6, the Falcon Heavy, the Space Launch System, as well as the Evolvable Deep-Space Habitat placed in EML2. A consistent part of the efforts in designing the ALCIDES mission accounts for innovative exploration scenarios: by analysing state of the art in robotics and planetary exploration, we introduce a mission architecture in which robots and humans collaborate to achieve several tasks, both autonomously and through cooperation. During this mission, high-performance mobility, extravehicular activity and habitation capabilities would be carried out and implemented. This project aims to demonstrate the human capability to live and work in the Lunar environment through the development of a long-term platform. We selected the Amundsen-Ganswindt basin as the landing site for multiple reasons: the possible presence of permanently shadowed regions, its position within the South Pole and its proximity to the Schrödinger basin. The main objectives of the ALCIDES mission are to study the Lunar cold trap volatiles, to gain understanding of the Lunar highlands geology through sampling and in-situ measurements and to study Human-Robotic interactions. In addition, factors such as psychology, legal issues and outreach regarding this mission were also considered. In particular, four traverses connecting the Amundsen crater with the Schrödinger basin were proposed, three of which to be performed by a tele-operated rover, and the remaining one to be carried out by a human crew with rover assistance. During these traverses, the rover will collect samples from several points of interest as well as perform in-situ measurements with a suite of instruments on board, helping to locate a convenient place for future human habitation. The ALCIDES mission results will help the scientific community to better understand the Moon and to take advantage of its resources for future space exploration. Gaining this knowledge will allow us to move forward in the development of systems and capabilities for manned missions to Mars and beyond. Highlights • International collaboration is a key point for ambitious space programs. • Human-Robot interaction is crucial for mission success and increasing performance. • Scientific goals should be the main objectives of space exploration missions. • Technologies to allow Lunar long-term research base are soon to be available. [ABSTRACT FROM AUTHOR]

Abstract: The current emphasis in the US and internationally on lunar robotic missions is generally viewed as a precursor to possible future human missions to the Moon. As initially framed, the implementation of high level policies such as the US Vision for Space Exploration (VSE) might have been limited to either human lunar sortie missions, or to the testing at the Moon of concepts-of-operations and systems for eventual human missions to Mars [White House, Vision for Space Exploration, Washington, DC, 14 January, 2004. ]. However, recently announced (December 2006) US goals go much further: these plans now place at the center of future US—and perhaps international—human spaceflight activities a long-term commitment to an outpost on the Moon. Based on available documents, a human lunar outpost could be emplaced as early as the 2020–2025 timeframe, and would involve numerous novel systems, new technologies and unique operations requirements. As such, substantial investments in research and development (R&D) will be necessary prior to, during, and following the deployment of such an outpost. It seems possible that such an outpost will be an international endeavor, not just the undertaking of a single country—and the US has actively courted partners in the VSE. However, critical questions remain concerning an international lunar outpost. What might such an outpost accomplish? To what extent will “sustainability” be built into the outpost? And, most importantly, what will be the outpost''s life cycle cost (LCC)? This paper will explore these issues with a view toward informing key policy and program decisions that must be made during the next several years. The paper will (1) describe a high-level analytical model of a modest lunar outpost, (2) examine (using this model) the parametric characteristics of the outpost in terms of the three critical questions indicated above, and (3) present rough estimates of the relationships of outpost goals and “sustainability” to LCC. The paper will also consider possible outpost requirements for near-term investments in enabling research in light of experiences in past advanced technology programs. [Copyright &y& Elsevier]

Abstract: In the frame of the ESA Aurora exploration program, the precision landing on Mars and Moon is of strategic importance because the ability to land on sites with high scientific interest is not a straightforward task. From here is the need to provide a dedicated test facility able to test Guidance, Navigation and Control (GNC) techniques and technologies, both vision and LIDAR based, in a realistic environment, in real time and as much as possible in a real scale. This is a fundamental step through which the planetary exploration will pass through in order to reduce the inherent risks associated with any landing mission. The ESA project named Precision Landing GNC Test Facility (PLGTF) has been conceived with this purpose, has been successfully started and, at the time of writing of the paper, has reached the detailed design phase. PLGTF will emulate a real lander dynamics during the powered descent phase in an atmospheric and non-atmospheric planetary environment, minimising the unavoidable scale factor to be applied. PLGTF is going to be the first ever-built facility with such a performance and it will be able to validate the entire GNC chain of a planetary landing system. The paper describes the PLGTF configuration for what concerns its first implementation, mainly devoted to validate the navigation function of a vision-based landing system and the associated sensor, and will also provide some preliminary information on the planned enhancements. [Copyright &y& Elsevier]

Lunar satellite in the polar orbit is the most popular concept in the recent and future lunar exploration missions for finding the water and other objectives. The motion and perturbed solution of lunar satellite are distinctly different from that of the earth satellite because the central body of the satellite, the Moon, is not the same as the Earth. In this paper, we use a set of non singular orbital elements, which is suitable for the lunar orbiter with 0 ≤ e < 1 and 0° ≤ i < 180°, to investigate the precise orbit determination for lunar satellite. Therefore, we could take the most advantage of both the analytical method and the numerical method. We give an overall strategy and make a simulation with the range data in this paper. The result is according with the theoretical analysis and suggests that this strategy have a practical prospect. [Copyright &y& Elsevier]

In this paper, the soft-landing analysis of a lunar lander spacecraft under three loading case was carried out in ABAQUS, using the Explicit Finite Element method. To ensure the simulation result's accuracy and reliability, the energy and mass balance criteria of the model was presented along with the theory and calculation method, and the results were benchmarked with other software (LS-DYNA) to get a validated model. The results from three loading case showed that the energy and mass of the models were conserved during soft landing, which satisfies the energy and mass balance criteria. The overloading response, structure steady state, and the crushing stroke of this lunar lander all met the design requirements of the lunar lander. The buffer energy-absorbing properties in this model have a good energy-absorbing capability, in which up to 84% of the initial energy could be dissipated. The design parameters of the model could guide the design of future manned landers or larger lunar landers. [ABSTRACT FROM AUTHOR]

Wheeled mobile robots (WMRs) often suffer from the longitudinal slipping when moving on the loose soil of the surface of the moon during exploration. Longitudinal slip is the main cause of WMRs' delay in trajectory tracking. In this paper, a nonlinear extended state observer (NESO) is introduced to estimate the longitudinal velocity in order to estimate the slip ratio and the derivative of the loss of velocity which are used in modelled disturbance compensation. Owing to the uncertainty and disturbance caused by estimation errors, a multi-objective controller using the mixed H 2 / H ∞ method is employed to ensure the robust stability and performance of the WMR system. The final inputs of the trajectory tracking consist of the feedforward compensation, compensation for the modelled disturbances and designed multi-objective control inputs. Finally, the simulation results demonstrate the effectiveness of the controller, which exhibits a satisfactory tracking performance. [ABSTRACT FROM AUTHOR]

For lunar surface exploration, a deployment system is necessary to allow a rover to leave the lander. The system should be as lightweight as possible and stored retracted when launched. In this paper, two types of retractable deployment systems for lunar landing missions, telescopic- and fold-type ramps, are discussed. In the telescopic-type system, a ramp is stored with the sections overlapping and slides out during deployment. In the fold-type system, it is stored folded and unfolds for the deployment. For the development of these ramps, a design concept study and structural analysis were conducted first. Subsequently, ramp deployment and rover release tests were performed using the developed ramp prototypes. Through these tests, the validity of their design concepts and functions have been confirmed. In the rover release test, it was observed that the developed lightweight ramp was sufficiently strong for a 50-kg rover to descend. This result suggests that this ramp system is suitable for the deployment of a 300-kg-class rover on the Moon, where the gravity is about one-sixth that on Earth. The lightweight and sturdy ramp developed in this study will contribute to both safe rover deployment and increase of lander/rover payload. [ABSTRACT FROM AUTHOR]

In this paper it is intended to discuss an approach to reduce design costs for subsequent missions by introducing modularity, commonality and multi-mission capability and thereby reuse of mission individual investments into the design of lunar exploration infrastructural systems. The presented approach has been developed within the German Helmholtz-Alliance on Robotic Exploration of Extreme Environments (ROBEX), a research alliance bringing together deep-sea and space research to jointly develop technologies and investigate problems for the exploration of highly inaccessible terrain – be it in the deep sea and polar regions or on the Moon and other planets. Although overall costs are much smaller for deep sea missions as compared to lunar missions, a lot can be learned from modularity approaches in deep sea research infrastructure design, which allows a high operational flexibility in the planning phase of a mission as well as during its implementation. The research presented here is based on a review of existing modular solutions in Earth orbiting satellites as well as science and exploration systems. This is followed by an investigation of lunar exploration scenarios from which we derive requirements for a multi-mission modular architecture. After analyzing possible options, an approach using a bus modular architecture for dedicated subsystems is presented. The approach is based on exchangeable modules e.g. incorporating instruments, which are added to the baseline system platform according to the demands of the specific scenario. It will be described in more detail, including arising problems e.g. in the power or thermal domain. Finally, technological building blocks to put the architecture into practical use will be described more in detail. [ABSTRACT FROM AUTHOR]

A novel concept for Chinese Chang'e-4 lunar exploration mission is presented in this paper at first. After the success of Chang'e-3, its backup probe, Chang'e-4 lander/rover combination, would be upgraded and land on the unexplored lunar farside by the aid of a relay satellite near the second Earth-Moon Lagrange point. Mineralogical and geochemical surveys on the farside to study the formation and evolution of lunar crust and observations at low radio frequencies to track the signals of the Universe's Dark Ages are priorities. Follow-up Chinese lunar exploration activities before 2030 are envisioned as building a robotic lunar science station by three to five missions. Finally several methods of international cooperation are proposed. [ABSTRACT FROM AUTHOR]

Lunar subsurface sampling is one of the critical technologies in the advancement of space exploration, and a lunar sampler with low weight, small volume, and low power consumption would significantly reduce the cost of space exploration. Thus, this paper proposes a novel miniature lunar sampler which adopts a flexible tape spring as its sampling arm. Compared with existing rigid-arm samplers, the proposed sampler has the merits of very low weight, reduced volume, and little power consumption. The mechanical design is illustrated in detail, the corresponding flexible kinematics model is built by considering flexibility compensation, and the working space of the sampler is depicted. The performance, e.g. the maximum acceleration, the maximum load capacity, and the sampling depth of the flexible arm, is analyzed through experiments, and each limit is established. In addition, the sampling process is demonstrated with the lab-based experiments, and the feasibility of the sampler is verified. [ABSTRACT FROM AUTHOR]

In the current wake of mission plans to the Moon and to Earth–Moon Libration points (EML) by several agencies and organizations, TYCHO identifies the key role of telecommunication provision for the future path of lunar exploration. It demonstrates an interesting extension to existing communication methods to the Moon and beyond by combining innovative technology with a next frontier location and the commercial space communication sector. It is evident that all communication systems will rely on direct communication to Earth ground stations. In case of EML-2 missions around HALO orbits or bases on the far side of the Moon, it has to be extended by communication links via relay stations. The innovative approach is that TYCHO provides this relay communication to those out-of-sight lunar missions as a service. TYCHO will establish a new infrastructure for future missions and even create a new market for add-on relay services. The TMA-0 satellite is TYCHO׳s first phase and a proposed demonstrator mission to the Earth–Moon Libration point EML-4. It demonstrates relay services needed for automated exploratory and manned missions (Moon bases) on the rim (>90°E and >90°W) and far side surface, to lunar orbits and even to EML-2 halo orbits (satellites and space stations). Its main advantage is the permanent availability of communication coverage. This will provide full access to scientific and telemetry data and furthermore to crucial medical monitoring and safety. The communication subsystem is a platform for conventional communication but also a test-bed for optical communication with high data-rate LASER links to serve the future needs of manned bases and periodic burst data-transfer from lunar poles. The operational TMA-1 satellite is a stand-alone mission integrated into existing space communication networks to provide open communication service to external lunar missions. Therefore the long-time stable libration points EML-4 and -5 are selected to guarantee an operation time of up to 10 years. It also enables measurements of the libration point environment with the scientific payloads. This includes sensors for space dust, solar and cosmic radiation activity for satellite lifetime estimation and lunar crew protection by providing early-warning systems. The paper describes the mission concept and the pre-design of the demonstrator satellite according to the operational mission requirements, advantages and benefits of this service. The concept was awarded with the Space Generation Advisory Council and OHB Scholarship in 2011 and the concept study is conducted at the Institute of Space Systems (IRS) [1] of the University of Stuttgart and OHB-System, Bremen [2] . [ABSTRACT FROM AUTHOR]

Abstract: Mars' moons Phobos and Deimos are low-albedo, D-type bodies that may preserve samples of outer solar system material that contributed organics and volatiles to the accreting terrestrial planets. A Discovery-class mission concept described in this paper, the Mars-Moon Exploration, Reconnaissance and Landed Investigation (MERLIN), will obtain in situ measurements from Deimos to test models for the moon's origin. The measurement objectives of MERLIN are to determine Deimos' elemental and mineralogical composition, to investigate its volatile and organic content, and to characterize processes that have modified its surface. To achieve these objectives, a landed payload will provide stereo imaging and measurements of elemental and mineralogical composition and interior structure. An orbital payload will acquire global high-resolution and color imaging, putting the landing site in context by characterizing Deimos' geology. Following MOI the spacecraft flies in formation with Deimos, and uses small changes in its orbit around Mars to investigate Deimos from a range of altitudes and illuminations over 4 months. Data taken during 1- to 2-km altitude flyovers will certify a landing site. The spacecraft will be delivered to a point several kilometers above Deimos, and will navigate to landing on a fresh exposure of regolith using onboard imaging. 90 days of baseline landed operations will provide a complete set of measurements, with schedule reserve, and there is sufficient propellant to repeat the measurements at a second site. [Copyright &y& Elsevier]

Abstract: Desert RATS objectives, hardware, locations, and participants have changed over time. This paper provides historical perspective on the original motivations for the Desert RATS analog, and an overview of the changes in RATS over time. The lessons learned from each year are synopsized. Finally, a preview of Desert RATS 2011 tests is included. [Copyright &y& Elsevier]

Abstract: The NASA Desert Research and Technology Studies (Desert RATS) is an annual field test of advanced concepts, prototype hardware, and potential modes of operation to be used on human planetary surface space exploration missions. For the 2009 and 2010 NASA Desert RATS field tests, various engineering concepts and operational exercises were incorporated into mission timelines with the focus of the majority of daily operations being on simulated lunar geological field operations and executed in a manner similar to current Space Shuttle and International Space Station missions. The field test for 2009 involved a two week lunar exploration simulation utilizing a two-man rover. The 2010 Desert RATS field test took this two week simulation further by incorporating a second two-man rover working in tandem with the 2009 rover, as well as including docked operations with a Pressurized Excursion Module (PEM). Personnel for the field test included the crew, a mission management team, engineering teams, a science team, and the mission operations team. The mission operations team served as the core of the Desert RATS mission control team and included certified NASA Mission Operations Directorate (MOD) flight controllers, former flight controllers, and astronaut personnel. The backgrounds of the flight controllers were in the areas of Extravehicular Activity (EVA), onboard mechanical systems and maintenance, robotics, timeline planning (OpsPlan), and spacecraft communicator (Capcom). With the simulated EVA operations, mechanized operations (the rover), and expectations of replanning, these flight control disciplines were especially well suited for the execution of the 2009 and 2010 Desert RATS field tests. The inclusion of an operations team has provided the added benefit of giving NASA mission operations flight control personnel the opportunity to begin examining operational mission control techniques, team compositions, and mission scenarios. This also gave the mission operations team the opportunity to gain insight into functional hardware requirements via lessons learned from executing the Desert RATS field test missions. This paper will detail the mission control team structure that was used during the 2009 and 2010 Desert RATS Lunar analog missions. It will also present a number of the lessons learned by the operations team during these field tests. Major lessons learned involved Mission Control Center (MCC) operations, pre-mission planning and training processes, procedure requirements, communication requirements, and logistic support for analogs. This knowledge will be applied to future Desert RATS field tests, and other Earth based analog testing for space exploration, to continue the evolution of manned space operations in preparation for human planetary exploration. It is important that operational knowledge for human space exploration missions be obtained during Earth-bound field tests to the greatest extent possible. This allows operations personnel the ability to examine various flight control and crew operations scenarios in preparation for actual space missions. [Copyright &y& Elsevier]

Abstract: The National Aeronautics and Space Administration (NASA) is working with international partners to develop the space architectures and mission plans necessary for human spaceflight beyond Earth orbit. The Apollo missions to the Moon demonstrated conclusively that surface mobility is a key asset that improves the efficiency of human explorers on a planetary surface. NASA's Desert Research and Technology Studies (Desert RATS), a multi-year series of tests of hardware and operations carried out annually in the high desert of Arizona, has tested a crewed pressurized rover concept referred to as the Space Exploration Vehicle (SEV). During NASA's Desert RATS 2010, four 2-person crews driving two SEVs collectively conducted 12 days of field exploration in the San Francisco Volcanic Field in northern Arizona. They collected 461 samples, with a total mass of 161.2kg, on 70 simulated extravehicular activities (EVAs). Each SEV crew traveled over 60km during their field explorations. This paper illustrates where the actual field sites, or ‘science stations’, were located, provides a brief description of the types of samples collected at each station, and highlights some of the more interesting sites. Most of the geologic samples collected at Desert RATS 2010 were well documented at the site of collection, and upon delivery to the Johnson Space Center the samples were given a preliminary examination. The samples are available for further study by interested researchers developing scientific instruments for use on the surfaces of the Moon and Mars, or for geological investigations of the San Francisco Volcanic Field. [Copyright &y& Elsevier]

Abstract: The Exploration Ground Data Systems (xGDS) project led by the Intelligent Robotics Group (IRG) at NASA Ames Research Center creates software tools to support multiple NASA-led planetary analog field experiments. The two primary tools that fall under the xGDS umbrella are the xGDS Web Tools (xGDS-WT) and Visual Environment for Remote Virtual Exploration (VERVE). IRG has also developed a hardware and software system that is closely integrated with our xGDS tools and is used in multiple field experiments called Gigapan Voyage. xGDS-WT, VERVE, and Gigapan Voyage are examples of IRG projects that improve the ratio of science return versus development effort by creating generic and reusable tools that leverage existing technologies in both hardware and software. xGDS Web Tools provides software for gathering and organizing mission data for science and engineering operations, including tools for planning traverses, monitoring autonomous or piloted vehicles, visualization, documentation, analysis, and search. VERVE provides high performance three dimensional (3D) user interfaces used by scientists, robot operators, and mission planners to visualize robot data in real time. Gigapan Voyage is a gigapixel image capturing and processing tool that improves situational awareness and scientific exploration in human and robotic analog missions. All of these technologies emphasize software reuse and leverage open source and/or commercial-off-the-shelf tools to greatly improve the utility and reduce the development and operational cost of future similar technologies. Over the past several years these technologies have been used in many NASA-led robotic field campaigns including the Desert Research and Technology Studies (DRATS), the Pavilion Lake Research Project (PLRP), the K10 Robotic Follow-Up tests, and most recently we have become involved in the NASA Extreme Environment Mission Operations (NEEMO) field experiments. A major objective of these joint robot and crew experiments is to improve NASAs understanding of how to most effectively execute and increase science return from exploration missions. This paper focuses on an integrated suite of xGDS software and compatible hardware tools: xGDS Web Tools, VERVE, and Gigapan Voyage, how they are used, and the design decisions that were made to allow them to be easily developed, integrated, tested, and reused by multiple NASA field experiments and robotic platforms. [Copyright &y& Elsevier]

Abstract: In recent years an increasing interest in the Moon surface operations has been experienced. In the future robotic and manned missions of Moon surface exploration will be fundamental in order to lay the groundwork for more ambitious space exploration programs. Surface mobility systems will be the key elements to ensure an efficient and safe Moon exploration. Future lunar rovers are likely to be heavier and able to travel longer distances than the previously developed Moon rover systems. The Lunar Roving Vehicle (LRV) is the only manned rover, which has so far been launched and used on the Moon surface. Its mobility system included flexible wheels that cannot be scaled to the heavier and longer range vehicles. Thus the previously developed wheels are likely not to be suitable for the new larger vehicles. Taking all these considerations into account, on the basis of the system requirements and assumptions, several wheel concepts have been discussed and evaluated through a trade-off analysis. Semi-empirical equations have been utilized to predict the wheel geometrical characteristics, as well as to estimate the motion resistances and the ability of the system to generate thrust. A numerical model has also been implemented, in order to define more into the details the whole wheel design, in terms of wheel geometry and physical properties. As a result of the trade-off analysis, the ellipse wheel concept has shown the best behavior in terms of stiffness, mass budget and dynamic performance. The results presented in the paper have been obtained in cooperation with Thales Alenia Space-Italy and Sicme motori, in the framework of a regional program called STEPS 1 [1] STEPS–Sistemi e Tecnologie per l''EsPlorazione Spaziale is a research project co-financed by Piedmont Region and firms and universities of the Piedmont Aerospace District in the ambit of the P.O.R-F.E.S.R. 2007–2013 program. . [Copyright &y& Elsevier]

Abstract: Mars is covered with a layer of dust that has been homogenized by global dust storms. Dust, levitated by these storms as well as by the frequent dust devils, is the dominant weather phenomenon on Mars. NASA''s Mars exploration rovers have shown that atmospheric dust falling on solar panels can decrease their efficiency to the point of rendering the rover unusable. Dust covering the surface of the moon is expected to be electrostatically charged due to the solar wind, cosmic rays, and the solar radiation itself through the photoelectric effect. Electrostatically charged dust has a large tendency to adhere to surfaces. The Apollo missions to the moon showed that lunar dust adhesion can hinder manned and unmanned exploration activities. In this paper, we report on our efforts to develop an electrodynamic dust shield to prevent the accumulation of dust on surfaces and to remove dust already adhering to those surfaces. The technology uses electrostatic and dielectrophoretic forces to carry dust particles off surfaces and to generate an electrodynamic shield that prevents further accumulation of dust. The concept of the electrodynamic dust shield was introduced by NASA in the late 1960s and later reduced to practice during the 1970s for terrestrial applications. In 2003, our laboratory, in collaboration with several universities, applied this technology to space applications, specifically to remove dust from solar panels on Mars. We show how, with an appropriate design, we can prevent the electrostatic breakdown at the low Martian atmospheric pressures. We are also able to show that uncharged dust can be lifted and removed from surfaces under simulated Martian environmental conditions. We have also been able to develop a version of the electrodynamic dust shield working under hard vacuum conditions that simulate the lunar environment. We have implemented the electrodynamic dust shield on solar arrays, optical systems, spectrometers, viewports, thermal radiators, batteries, and power systems, as well as on fabrics for spacesuits. We present data on the design and optimization of the electrodynamic dust shields and provide data on the performance of the different implementations of the technology for lunar and Martian exploration activities. [Copyright &y& Elsevier]

Abstract: JAXA is planning exploration missions to the moon, following upon the Kaguya (SELENE) mission., These missions aim to demonstrate some new technologies, observe the moon scientifically, investigate technical, social and political feasibility of utilizing the moon. For the first step of the missions, the phase A study of SELENE-2 has started from the summer of 2007. This mission will demonstrate the effectiveness of several technologies including precision landing, hazard avoidance, surface mobility, and night survival technologies. In situ geological and geophysical observations will be conducted to improve our knowledge on the origin and the evolution of the moon. Investigating the lunar surface conditions and its potential for in situ resource utilization will provide key information for future human exploration missions. This paper presents the current status of the SELENE-2 mission, its objectives, its design, and other important aspects of its development such as international cooperation. [Copyright &y& Elsevier]